summaryrefslogtreecommitdiffstats
path: root/src/widgets/itemviews/qlistview.cpp
blob: 396d84de9cd0232b403777a1cc0b6a2a3f5fb640 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2013 Samuel Gaist <samuel.gaist@deltech.ch>
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtWidgets module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qlistview.h"

#ifndef QT_NO_LISTVIEW
#include <qabstractitemdelegate.h>
#include <qapplication.h>
#include <qpainter.h>
#include <qbitmap.h>
#include <qdrag.h>
#include <qvector.h>
#include <qstyle.h>
#include <qevent.h>
#include <qscrollbar.h>
#include <qrubberband.h>
#include <private/qlistview_p.h>
#include <private/qscrollbar_p.h>
#include <qdebug.h>
#ifndef QT_NO_ACCESSIBILITY
#include <qaccessible.h>
#endif

#include <algorithm>

QT_BEGIN_NAMESPACE

extern bool qt_sendSpontaneousEvent(QObject *receiver, QEvent *event);

/*!
    \class QListView

    \brief The QListView class provides a list or icon view onto a model.

    \ingroup model-view
    \ingroup advanced
    \inmodule QtWidgets

    \image windows-listview.png

    A QListView presents items stored in a model, either as a simple
    non-hierarchical list, or as a collection of icons. This class is used
    to provide lists and icon views that were previously provided by the
    \c QListBox and \c QIconView classes, but using the more flexible
    approach provided by Qt's model/view architecture.

    The QListView class is one of the \l{Model/View Classes}
    and is part of Qt's \l{Model/View Programming}{model/view framework}.

    This view does not display horizontal or vertical headers; to display
    a list of items with a horizontal header, use QTreeView instead.

    QListView implements the interfaces defined by the
    QAbstractItemView class to allow it to display data provided by
    models derived from the QAbstractItemModel class.

    Items in a list view can be displayed using one of two view modes:
    In \l ListMode, the items are displayed in the form of a simple list;
    in \l IconMode, the list view takes the form of an \e{icon view} in
    which the items are displayed with icons like files in a file manager.
    By default, the list view is in \l ListMode. To change the view mode,
    use the setViewMode() function, and to determine the current view mode,
    use viewMode().

    Items in these views are laid out in the direction specified by the
    flow() of the list view. The items may be fixed in place, or allowed
    to move, depending on the view's movement() state.

    If the items in the model cannot be completely laid out in the
    direction of flow, they can be wrapped at the boundary of the view
    widget; this depends on isWrapping(). This property is useful when the
    items are being represented by an icon view.

    The resizeMode() and layoutMode() govern how and when the items are
    laid out. Items are spaced according to their spacing(), and can exist
    within a notional grid of size specified by gridSize(). The items can
    be rendered as large or small icons depending on their iconSize().

    \section1 Improving Performance

    It is possible to give the view hints about the data it is handling in order
    to improve its performance when displaying large numbers of items. One approach
    that can be taken for views that are intended to display items with equal sizes
    is to set the \l uniformItemSizes property to true.

    \sa {View Classes}, {Item Views Puzzle Example}, QTreeView, QTableView, QListWidget
*/

/*!
    \enum QListView::ViewMode

    \value ListMode The items are laid out using TopToBottom flow, with Small size and Static movement
    \value IconMode The items are laid out using LeftToRight flow, with Large size and Free movement
*/

/*!
  \enum QListView::Movement

  \value Static The items cannot be moved by the user.
  \value Free The items can be moved freely by the user.
  \value Snap The items snap to the specified grid when moved; see
  setGridSize().
*/

/*!
  \enum QListView::Flow

  \value LeftToRight The items are laid out in the view from the left
  to the right.
  \value TopToBottom The items are laid out in the view from the top
  to the bottom.
*/

/*!
  \enum QListView::ResizeMode

  \value Fixed The items will only be laid out the first time the view is shown.
  \value Adjust The items will be laid out every time the view is resized.
*/

/*!
  \enum QListView::LayoutMode

  \value SinglePass The items are laid out all at once.
  \value Batched The items are laid out in batches of \l batchSize items.
  \sa batchSize
*/

/*!
  \since 4.2
  \fn void QListView::indexesMoved(const QModelIndexList &indexes)

  This signal is emitted when the specified \a indexes are moved in the view.
*/

/*!
    Creates a new QListView with the given \a parent to view a model.
    Use setModel() to set the model.
*/
QListView::QListView(QWidget *parent)
    : QAbstractItemView(*new QListViewPrivate, parent)
{
    setViewMode(ListMode);
    setSelectionMode(SingleSelection);
    setAttribute(Qt::WA_MacShowFocusRect);
    Q_D(QListView);               // We rely on a qobject_cast for PM_DefaultFrameWidth to change
    d->updateStyledFrameWidths(); // hence we have to force an update now that the object has been constructed
}

/*!
  \internal
*/
QListView::QListView(QListViewPrivate &dd, QWidget *parent)
    : QAbstractItemView(dd, parent)
{
    setViewMode(ListMode);
    setSelectionMode(SingleSelection);
    setAttribute(Qt::WA_MacShowFocusRect);
    Q_D(QListView);               // We rely on a qobject_cast for PM_DefaultFrameWidth to change
    d->updateStyledFrameWidths(); // hence we have to force an update now that the object has been constructed
}

/*!
  Destroys the view.
*/
QListView::~QListView()
{
}

/*!
    \property QListView::movement
    \brief whether the items can be moved freely, are snapped to a
    grid, or cannot be moved at all.

    This property determines how the user can move the items in the
    view. \l Static means that the items can't be moved the user. \l
    Free means that the user can drag and drop the items to any
    position in the view. \l Snap means that the user can drag and
    drop the items, but only to the positions in a notional grid
    signified by the gridSize property.

    Setting this property when the view is visible will cause the
    items to be laid out again.

    By default, this property is set to \l Static.

    \sa gridSize, resizeMode, viewMode
*/
void QListView::setMovement(Movement movement)
{
    Q_D(QListView);
    d->modeProperties |= uint(QListViewPrivate::Movement);
    d->movement = movement;

#ifndef QT_NO_DRAGANDDROP
    bool movable = (movement != Static);
    setDragEnabled(movable);
    d->viewport->setAcceptDrops(movable);
#endif
    d->doDelayedItemsLayout();
}

QListView::Movement QListView::movement() const
{
    Q_D(const QListView);
    return d->movement;
}

/*!
    \property QListView::flow
    \brief which direction the items layout should flow.

    If this property is \l LeftToRight, the items will be laid out left
    to right. If the \l isWrapping property is \c true, the layout will wrap
    when it reaches the right side of the visible area. If this
    property is \l TopToBottom, the items will be laid out from the top
    of the visible area, wrapping when it reaches the bottom.

    Setting this property when the view is visible will cause the
    items to be laid out again.

    By default, this property is set to \l TopToBottom.

    \sa viewMode
*/
void QListView::setFlow(Flow flow)
{
    Q_D(QListView);
    d->modeProperties |= uint(QListViewPrivate::Flow);
    d->flow = flow;
    d->doDelayedItemsLayout();
}

QListView::Flow QListView::flow() const
{
    Q_D(const QListView);
    return d->flow;
}

/*!
    \property QListView::isWrapping
    \brief whether the items layout should wrap.

    This property holds whether the layout should wrap when there is
    no more space in the visible area. The point at which the layout wraps
    depends on the \l flow property.

    Setting this property when the view is visible will cause the
    items to be laid out again.

    By default, this property is \c false.

    \sa viewMode
*/
void QListView::setWrapping(bool enable)
{
    Q_D(QListView);
    d->modeProperties |= uint(QListViewPrivate::Wrap);
    d->setWrapping(enable);
    d->doDelayedItemsLayout();
}

bool QListView::isWrapping() const
{
    Q_D(const QListView);
    return d->isWrapping();
}

/*!
    \property QListView::resizeMode
    \brief whether the items are laid out again when the view is resized.

    If this property is \l Adjust, the items will be laid out again
    when the view is resized. If the value is \l Fixed, the items will
    not be laid out when the view is resized.

    By default, this property is set to \l Fixed.

    \sa movement, gridSize, viewMode
*/
void QListView::setResizeMode(ResizeMode mode)
{
    Q_D(QListView);
    d->modeProperties |= uint(QListViewPrivate::ResizeMode);
    d->resizeMode = mode;
}

QListView::ResizeMode QListView::resizeMode() const
{
    Q_D(const QListView);
    return d->resizeMode;
}

/*!
    \property QListView::layoutMode
    \brief determines whether the layout of items should happen immediately or be delayed.

    This property holds the layout mode for the items. When the mode
    is \l SinglePass (the default), the items are laid out all in one go.
    When the mode is \l Batched, the items are laid out in batches of \l batchSize
    items, while processing events. This makes it possible to
    instantly view and interact with the visible items while the rest
    are being laid out.

    \sa viewMode
*/
void QListView::setLayoutMode(LayoutMode mode)
{
    Q_D(QListView);
    d->layoutMode = mode;
}

QListView::LayoutMode QListView::layoutMode() const
{
    Q_D(const QListView);
    return d->layoutMode;
}

/*!
    \property QListView::spacing
    \brief the space around the items in the layout

    This property is the size of the empty space that is padded around
    an item in the layout.

    Setting this property when the view is visible will cause the
    items to be laid out again.

    By default, this property contains a value of 0.

    \sa viewMode
*/
void QListView::setSpacing(int space)
{
    Q_D(QListView);
    d->modeProperties |= uint(QListViewPrivate::Spacing);
    d->setSpacing(space);
    d->doDelayedItemsLayout();
}

int QListView::spacing() const
{
    Q_D(const QListView);
    return d->spacing();
}

/*!
    \property QListView::batchSize
    \brief the number of items laid out in each batch if \l layoutMode is
    set to \l Batched

    The default value is 100.

    \since 4.2
*/

void QListView::setBatchSize(int batchSize)
{
    Q_D(QListView);
    if (Q_UNLIKELY(batchSize <= 0)) {
        qWarning("Invalid batchSize (%d)", batchSize);
        return;
    }
    d->batchSize = batchSize;
}

int QListView::batchSize() const
{
    Q_D(const QListView);
    return d->batchSize;
}

/*!
    \property QListView::gridSize
    \brief the size of the layout grid

    This property is the size of the grid in which the items are laid
    out. The default is an empty size which means that there is no
    grid and the layout is not done in a grid. Setting this property
    to a non-empty size switches on the grid layout. (When a grid
    layout is in force the \l spacing property is ignored.)

    Setting this property when the view is visible will cause the
    items to be laid out again.

    \sa viewMode
*/
void QListView::setGridSize(const QSize &size)
{
    Q_D(QListView);
    d->modeProperties |= uint(QListViewPrivate::GridSize);
    d->setGridSize(size);
    d->doDelayedItemsLayout();
}

QSize QListView::gridSize() const
{
    Q_D(const QListView);
    return d->gridSize();
}

/*!
    \property QListView::viewMode
    \brief the view mode of the QListView.

    This property will change the other unset properties to conform
    with the set view mode. QListView-specific properties that have already been set
    will not be changed, unless clearPropertyFlags() has been called.

    Setting the view mode will enable or disable drag and drop based on the
    selected movement. For ListMode, the default movement is \l Static
    (drag and drop disabled); for IconMode, the default movement is
    \l Free (drag and drop enabled).

    \sa isWrapping, spacing, gridSize, flow, movement, resizeMode
*/
void QListView::setViewMode(ViewMode mode)
{
    Q_D(QListView);
    if (d->commonListView && d->viewMode == mode)
        return;
    d->viewMode = mode;

    delete d->commonListView;
    if (mode == ListMode) {
        d->commonListView = new QListModeViewBase(this, d);
        if (!(d->modeProperties & QListViewPrivate::Wrap))
            d->setWrapping(false);
        if (!(d->modeProperties & QListViewPrivate::Spacing))
            d->setSpacing(0);
        if (!(d->modeProperties & QListViewPrivate::GridSize))
            d->setGridSize(QSize());
        if (!(d->modeProperties & QListViewPrivate::Flow))
            d->flow = TopToBottom;
        if (!(d->modeProperties & QListViewPrivate::Movement))
            d->movement = Static;
        if (!(d->modeProperties & QListViewPrivate::ResizeMode))
            d->resizeMode = Fixed;
        if (!(d->modeProperties & QListViewPrivate::SelectionRectVisible))
            d->showElasticBand = false;
    } else {
        d->commonListView = new QIconModeViewBase(this, d);
        if (!(d->modeProperties & QListViewPrivate::Wrap))
            d->setWrapping(true);
        if (!(d->modeProperties & QListViewPrivate::Spacing))
            d->setSpacing(0);
        if (!(d->modeProperties & QListViewPrivate::GridSize))
            d->setGridSize(QSize());
        if (!(d->modeProperties & QListViewPrivate::Flow))
            d->flow = LeftToRight;
        if (!(d->modeProperties & QListViewPrivate::Movement))
            d->movement = Free;
        if (!(d->modeProperties & QListViewPrivate::ResizeMode))
            d->resizeMode = Fixed;
        if (!(d->modeProperties & QListViewPrivate::SelectionRectVisible))
            d->showElasticBand = true;
    }

#ifndef QT_NO_DRAGANDDROP
    bool movable = (d->movement != Static);
    setDragEnabled(movable);
    setAcceptDrops(movable);
#endif
    d->clear();
    d->doDelayedItemsLayout();
}

QListView::ViewMode QListView::viewMode() const
{
    Q_D(const QListView);
    return d->viewMode;
}

/*!
    Clears the QListView-specific property flags. See \l{viewMode}.

    Properties inherited from QAbstractItemView are not covered by the
    property flags. Specifically, \l{QAbstractItemView::dragEnabled}
    {dragEnabled} and \l{QAbstractItemView::acceptDrops}
    {acceptsDrops} are computed by QListView when calling
    setMovement() or setViewMode().
*/
void QListView::clearPropertyFlags()
{
    Q_D(QListView);
    d->modeProperties = 0;
}

/*!
    Returns \c true if the \a row is hidden; otherwise returns \c false.
*/
bool QListView::isRowHidden(int row) const
{
    Q_D(const QListView);
    return d->isHidden(row);
}

/*!
    If \a hide is true, the given \a row will be hidden; otherwise
    the \a row will be shown.
*/
void QListView::setRowHidden(int row, bool hide)
{
    Q_D(QListView);
    const bool hidden = d->isHidden(row);
    if (hide && !hidden)
        d->commonListView->appendHiddenRow(row);
    else if (!hide && hidden)
        d->commonListView->removeHiddenRow(row);
    d->doDelayedItemsLayout();
    d->viewport->update();
}

/*!
  \reimp
*/
QRect QListView::visualRect(const QModelIndex &index) const
{
    Q_D(const QListView);
    return d->mapToViewport(rectForIndex(index));
}

/*!
  \reimp
*/
void QListView::scrollTo(const QModelIndex &index, ScrollHint hint)
{
    Q_D(QListView);

    if (index.parent() != d->root || index.column() != d->column)
        return;

    const QRect rect = visualRect(index);
    if (hint == EnsureVisible && d->viewport->rect().contains(rect)) {
        d->viewport->update(rect);
        return;
    }

    if (d->flow == QListView::TopToBottom || d->isWrapping()) // vertical
        verticalScrollBar()->setValue(d->verticalScrollToValue(index, rect, hint));

    if (d->flow == QListView::LeftToRight || d->isWrapping()) // horizontal
        horizontalScrollBar()->setValue(d->horizontalScrollToValue(index, rect, hint));
}

int QListViewPrivate::horizontalScrollToValue(const QModelIndex &index, const QRect &rect,
                                              QListView::ScrollHint hint) const
{
    Q_Q(const QListView);
    const QRect area = viewport->rect();
    const bool leftOf = q->isRightToLeft()
                        ? (rect.left() < area.left()) && (rect.right() < area.right())
                        : rect.left() < area.left();
    const bool rightOf = q->isRightToLeft()
                         ? rect.right() > area.right()
                         : (rect.right() > area.right()) && (rect.left() > area.left());
    return commonListView->horizontalScrollToValue(q->visualIndex(index), hint, leftOf, rightOf, area, rect);
}

int QListViewPrivate::verticalScrollToValue(const QModelIndex &index, const QRect &rect,
                                            QListView::ScrollHint hint) const
{
    Q_Q(const QListView);
    const QRect area = viewport->rect();
    const bool above = (hint == QListView::EnsureVisible && rect.top() < area.top());
    const bool below = (hint == QListView::EnsureVisible && rect.bottom() > area.bottom());
    return commonListView->verticalScrollToValue(q->visualIndex(index), hint, above, below, area, rect);
}

void QListViewPrivate::selectAll(QItemSelectionModel::SelectionFlags command)
{
    if (!selectionModel)
        return;

    QItemSelection selection;
    QModelIndex topLeft;
    int row = 0;
    const int colCount = model->columnCount(root);
    for(; row < model->rowCount(root); ++row) {
        if (isHidden(row)) {
            //it might be the end of a selection range
            if (topLeft.isValid()) {
                QModelIndex bottomRight = model->index(row - 1, colCount - 1, root);
                selection.append(QItemSelectionRange(topLeft, bottomRight));
                topLeft = QModelIndex();
            }
            continue;
        }

        if (!topLeft.isValid()) //start of a new selection range
            topLeft = model->index(row, 0, root);
    }

    if (topLeft.isValid()) {
        //last selected range
        QModelIndex bottomRight = model->index(row - 1, colCount - 1, root);
        selection.append(QItemSelectionRange(topLeft, bottomRight));
    }

    if (!selection.isEmpty())
        selectionModel->select(selection, command);
}

/*!
  \reimp

  We have a QListView way of knowing what elements are on the viewport
  through the intersectingSet function
*/
QItemViewPaintPairs QListViewPrivate::draggablePaintPairs(const QModelIndexList &indexes, QRect *r) const
{
    Q_ASSERT(r);
    Q_Q(const QListView);
    QRect &rect = *r;
    const QRect viewportRect = viewport->rect();
    QItemViewPaintPairs ret;
    QVector<QModelIndex> visibleIndexes = intersectingSet(viewportRect.translated(q->horizontalOffset(), q->verticalOffset()));
    std::sort(visibleIndexes.begin(), visibleIndexes.end());
    for (const auto &index : indexes) {
        if (std::binary_search(visibleIndexes.cbegin(), visibleIndexes.cend(), index)) {
            const QRect current = q->visualRect(index);
            QItemViewPaintPair p = { current, index };
            ret += p;
            rect |= current;
        }
    }
    rect &= viewportRect;
    return ret;
}

/*!
  \internal
*/
void QListView::reset()
{
    Q_D(QListView);
    d->clear();
    d->hiddenRows.clear();
    QAbstractItemView::reset();
}

/*!
  \internal
*/
void QListView::setRootIndex(const QModelIndex &index)
{
    Q_D(QListView);
    d->column = qBound(0, d->column, d->model->columnCount(index) - 1);
    QAbstractItemView::setRootIndex(index);
    // sometimes we get an update before reset() is called
    d->clear();
    d->hiddenRows.clear();
}

/*!
    \internal

    Scroll the view contents by \a dx and \a dy.
*/

void QListView::scrollContentsBy(int dx, int dy)
{
    Q_D(QListView);
    d->delayedAutoScroll.stop(); // auto scroll was canceled by the user scrolling
    d->commonListView->scrollContentsBy(dx, dy, d->state == QListView::DragSelectingState);
}

/*!
    \internal

    Resize the internal contents to \a width and \a height and set the
    scroll bar ranges accordingly.
*/
void QListView::resizeContents(int width, int height)
{
    Q_D(QListView);
    d->setContentsSize(width, height);
}

/*!
    \internal
*/
QSize QListView::contentsSize() const
{
    Q_D(const QListView);
    return d->contentsSize();
}

/*!
  \reimp
*/
void QListView::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles)
{
    d_func()->commonListView->dataChanged(topLeft, bottomRight);
    QAbstractItemView::dataChanged(topLeft, bottomRight, roles);
}

/*!
  \reimp
*/
void QListView::rowsInserted(const QModelIndex &parent, int start, int end)
{
    Q_D(QListView);
    // ### be smarter about inserted items
    d->clear();
    d->doDelayedItemsLayout();
    QAbstractItemView::rowsInserted(parent, start, end);
}

/*!
  \reimp
*/
void QListView::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end)
{
    Q_D(QListView);
    // if the parent is above d->root in the tree, nothing will happen
    QAbstractItemView::rowsAboutToBeRemoved(parent, start, end);
    if (parent == d->root) {
        QSet<QPersistentModelIndex>::iterator it = d->hiddenRows.begin();
        while (it != d->hiddenRows.end()) {
            int hiddenRow = it->row();
            if (hiddenRow >= start && hiddenRow <= end) {
                it = d->hiddenRows.erase(it);
            } else {
                ++it;
            }
        }
    }
    d->clear();
    d->doDelayedItemsLayout();
}

/*!
  \reimp
*/
void QListView::mouseMoveEvent(QMouseEvent *e)
{
    if (!isVisible())
        return;
    Q_D(QListView);
    QAbstractItemView::mouseMoveEvent(e);
    if (state() == DragSelectingState
        && d->showElasticBand
        && d->selectionMode != SingleSelection
        && d->selectionMode != NoSelection) {
        QRect rect(d->pressedPosition, e->pos() + QPoint(horizontalOffset(), verticalOffset()));
        rect = rect.normalized();
        d->viewport->update(d->mapToViewport(rect.united(d->elasticBand)));
        d->elasticBand = rect;
    }
}

/*!
  \reimp
*/
void QListView::mouseReleaseEvent(QMouseEvent *e)
{
    Q_D(QListView);
    QAbstractItemView::mouseReleaseEvent(e);
    // #### move this implementation into a dynamic class
    if (d->showElasticBand && d->elasticBand.isValid()) {
        d->viewport->update(d->mapToViewport(d->elasticBand));
        d->elasticBand = QRect();
    }
}

#if QT_CONFIG(wheelevent)
/*!
  \reimp
*/
void QListView::wheelEvent(QWheelEvent *e)
{
    Q_D(QListView);
    if (e->orientation() == Qt::Vertical) {
        if (e->angleDelta().x() == 0
            && ((d->flow == TopToBottom && d->wrap) || (d->flow == LeftToRight && !d->wrap))
            && d->vbar->minimum() == 0 && d->vbar->maximum() == 0) {
            QPoint pixelDelta(e->pixelDelta().y(), e->pixelDelta().x());
            QPoint angleDelta(e->angleDelta().y(), e->angleDelta().x());
            QWheelEvent hwe(e->pos(), e->globalPos(), pixelDelta, angleDelta, e->delta(),
                            Qt::Horizontal, e->buttons(), e->modifiers(), e->phase(), e->source(), e->inverted());
            if (e->spontaneous())
                qt_sendSpontaneousEvent(d->hbar, &hwe);
            else
                QApplication::sendEvent(d->hbar, &hwe);
            e->setAccepted(hwe.isAccepted());
        } else {
            QApplication::sendEvent(d->vbar, e);
        }
    } else {
        QApplication::sendEvent(d->hbar, e);
    }
}
#endif // QT_CONFIG(wheelevent)

/*!
  \reimp
*/
void QListView::timerEvent(QTimerEvent *e)
{
    Q_D(QListView);
    if (e->timerId() == d->batchLayoutTimer.timerId()) {
        if (d->doItemsLayout(d->batchSize)) { // layout is done
            d->batchLayoutTimer.stop();
            updateGeometries();
            d->viewport->update();
        }
    }
    QAbstractItemView::timerEvent(e);
}

/*!
  \reimp
*/
void QListView::resizeEvent(QResizeEvent *e)
{
    Q_D(QListView);
    if (d->delayedPendingLayout)
        return;

    QSize delta = e->size() - e->oldSize();

    if (delta.isNull())
      return;

    bool listWrap = (d->viewMode == ListMode) && d->wrapItemText;
    bool flowDimensionChanged = (d->flow == LeftToRight && delta.width() != 0)
                                || (d->flow == TopToBottom && delta.height() != 0);

    // We post a delayed relayout in the following cases :
    // - we're wrapping
    // - the state is NoState, we're adjusting and the size has changed in the flowing direction
    if (listWrap
        || (state() == NoState && d->resizeMode == Adjust && flowDimensionChanged)) {
        d->doDelayedItemsLayout(100); // wait 1/10 sec before starting the layout
    } else {
        QAbstractItemView::resizeEvent(e);
    }
}

#ifndef QT_NO_DRAGANDDROP

/*!
  \reimp
*/
void QListView::dragMoveEvent(QDragMoveEvent *e)
{
    Q_D(QListView);
    if (!d->commonListView->filterDragMoveEvent(e)) {
        if (viewMode() == QListView::ListMode && flow() == QListView::LeftToRight)
            static_cast<QListModeViewBase *>(d->commonListView)->dragMoveEvent(e);
        else
            QAbstractItemView::dragMoveEvent(e);
    }
}


/*!
  \reimp
*/
void QListView::dragLeaveEvent(QDragLeaveEvent *e)
{
    if (!d_func()->commonListView->filterDragLeaveEvent(e))
        QAbstractItemView::dragLeaveEvent(e);
}

/*!
  \reimp
*/
void QListView::dropEvent(QDropEvent *e)
{
    if (!d_func()->commonListView->filterDropEvent(e))
        QAbstractItemView::dropEvent(e);
}

/*!
  \reimp
*/
void QListView::startDrag(Qt::DropActions supportedActions)
{
    if (!d_func()->commonListView->filterStartDrag(supportedActions))
        QAbstractItemView::startDrag(supportedActions);
}

#endif // QT_NO_DRAGANDDROP

/*!
  \reimp
*/
QStyleOptionViewItem QListView::viewOptions() const
{
    Q_D(const QListView);
    QStyleOptionViewItem option = QAbstractItemView::viewOptions();
    if (!d->iconSize.isValid()) { // otherwise it was already set in abstractitemview
        int pm = (d->viewMode == QListView::ListMode
                  ? style()->pixelMetric(QStyle::PM_ListViewIconSize, 0, this)
                  : style()->pixelMetric(QStyle::PM_IconViewIconSize, 0, this));
        option.decorationSize = QSize(pm, pm);
    }
    if (d->viewMode == QListView::IconMode) {
        option.showDecorationSelected = false;
        option.decorationPosition = QStyleOptionViewItem::Top;
        option.displayAlignment = Qt::AlignCenter;
    } else {
        option.decorationPosition = QStyleOptionViewItem::Left;
    }

    if (d->gridSize().isValid()) {
        option.rect.setSize(d->gridSize());
    }

    return option;
}


/*!
  \reimp
*/
void QListView::paintEvent(QPaintEvent *e)
{
    Q_D(QListView);
    if (!d->itemDelegate)
        return;
    QStyleOptionViewItem option = d->viewOptionsV1();
    QPainter painter(d->viewport);

    const QVector<QModelIndex> toBeRendered = d->intersectingSet(e->rect().translated(horizontalOffset(), verticalOffset()), false);

    const QModelIndex current = currentIndex();
    const QModelIndex hover = d->hover;
    const QAbstractItemModel *itemModel = d->model;
    const QItemSelectionModel *selections = d->selectionModel;
    const bool focus = (hasFocus() || d->viewport->hasFocus()) && current.isValid();
    const bool alternate = d->alternatingColors;
    const QStyle::State state = option.state;
    const QAbstractItemView::State viewState = this->state();
    const bool enabled = (state & QStyle::State_Enabled) != 0;

    bool alternateBase = false;
    int previousRow = -2; // trigger the alternateBase adjustment on first pass

    int maxSize = (flow() == TopToBottom)
        ? qMax(viewport()->size().width(), d->contentsSize().width()) - 2 * d->spacing()
        : qMax(viewport()->size().height(), d->contentsSize().height()) - 2 * d->spacing();

    QVector<QModelIndex>::const_iterator end = toBeRendered.constEnd();
    for (QVector<QModelIndex>::const_iterator it = toBeRendered.constBegin(); it != end; ++it) {
        Q_ASSERT((*it).isValid());
        option.rect = visualRect(*it);

        if (flow() == TopToBottom)
            option.rect.setWidth(qMin(maxSize, option.rect.width()));
        else
            option.rect.setHeight(qMin(maxSize, option.rect.height()));

        option.state = state;
        if (selections && selections->isSelected(*it))
            option.state |= QStyle::State_Selected;
        if (enabled) {
            QPalette::ColorGroup cg;
            if ((itemModel->flags(*it) & Qt::ItemIsEnabled) == 0) {
                option.state &= ~QStyle::State_Enabled;
                cg = QPalette::Disabled;
            } else {
                cg = QPalette::Normal;
            }
            option.palette.setCurrentColorGroup(cg);
        }
        if (focus && current == *it) {
            option.state |= QStyle::State_HasFocus;
            if (viewState == EditingState)
                option.state |= QStyle::State_Editing;
        }
        option.state.setFlag(QStyle::State_MouseOver, *it == hover);

        if (alternate) {
            int row = (*it).row();
            if (row != previousRow + 1) {
                // adjust alternateBase according to rows in the "gap"
                if (!d->hiddenRows.isEmpty()) {
                    for (int r = qMax(previousRow + 1, 0); r < row; ++r) {
                        if (!d->isHidden(r))
                            alternateBase = !alternateBase;
                    }
                } else {
                    alternateBase = (row & 1) != 0;
                }
            }
            option.features.setFlag(QStyleOptionViewItem::Alternate, alternateBase);

            // draw background of the item (only alternate row). rest of the background
            // is provided by the delegate
            QStyle::State oldState = option.state;
            option.state &= ~QStyle::State_Selected;
            style()->drawPrimitive(QStyle::PE_PanelItemViewRow, &option, &painter, this);
            option.state = oldState;

            alternateBase = !alternateBase;
            previousRow = row;
        }

        d->delegateForIndex(*it)->paint(&painter, option, *it);
    }

#ifndef QT_NO_DRAGANDDROP
    d->commonListView->paintDragDrop(&painter);
#endif

#ifndef QT_NO_RUBBERBAND
    // #### move this implementation into a dynamic class
    if (d->showElasticBand && d->elasticBand.isValid()) {
        QStyleOptionRubberBand opt;
        opt.initFrom(this);
        opt.shape = QRubberBand::Rectangle;
        opt.opaque = false;
        opt.rect = d->mapToViewport(d->elasticBand, false).intersected(
            d->viewport->rect().adjusted(-16, -16, 16, 16));
        painter.save();
        style()->drawControl(QStyle::CE_RubberBand, &opt, &painter);
        painter.restore();
    }
#endif
}

/*!
  \reimp
*/
QModelIndex QListView::indexAt(const QPoint &p) const
{
    Q_D(const QListView);
    QRect rect(p.x() + horizontalOffset(), p.y() + verticalOffset(), 1, 1);
    const QVector<QModelIndex> intersectVector = d->intersectingSet(rect);
    QModelIndex index = intersectVector.count() > 0
                        ? intersectVector.last() : QModelIndex();
    if (index.isValid() && visualRect(index).contains(p))
        return index;
    return QModelIndex();
}

/*!
  \reimp
*/
int QListView::horizontalOffset() const
{
    return d_func()->commonListView->horizontalOffset();
}

/*!
  \reimp
*/
int QListView::verticalOffset() const
{
    return d_func()->commonListView->verticalOffset();
}

/*!
  \reimp
*/
QModelIndex QListView::moveCursor(CursorAction cursorAction, Qt::KeyboardModifiers modifiers)
{
    Q_D(QListView);
    Q_UNUSED(modifiers);

    QModelIndex current = currentIndex();
    if (!current.isValid()) {
        int rowCount = d->model->rowCount(d->root);
        if (!rowCount)
            return QModelIndex();
        int row = 0;
        while (row < rowCount && d->isHiddenOrDisabled(row))
            ++row;
        if (row >= rowCount)
            return QModelIndex();
        return d->model->index(row, d->column, d->root);
    }

    const QRect initialRect = rectForIndex(current);
    QRect rect = initialRect;
    if (rect.isEmpty()) {
        return d->model->index(0, d->column, d->root);
    }
    if (d->gridSize().isValid()) rect.setSize(d->gridSize());

    QSize contents = d->contentsSize();
    QVector<QModelIndex> intersectVector;

    switch (cursorAction) {
    case MoveLeft:
        while (intersectVector.isEmpty()) {
            rect.translate(-rect.width(), 0);
            if (rect.right() <= 0)
                return current;
            if (rect.left() < 0)
                rect.setLeft(0);
            intersectVector = d->intersectingSet(rect);
            d->removeCurrentAndDisabled(&intersectVector, current);
        }
        return d->closestIndex(initialRect, intersectVector);
    case MoveRight:
        while (intersectVector.isEmpty()) {
            rect.translate(rect.width(), 0);
            if (rect.left() >= contents.width())
                return current;
            if (rect.right() > contents.width())
                rect.setRight(contents.width());
            intersectVector = d->intersectingSet(rect);
            d->removeCurrentAndDisabled(&intersectVector, current);
        }
        return d->closestIndex(initialRect, intersectVector);
    case MovePageUp:
        // move current by (visibileRowCount - 1) items.
        // rect.translate(0, -rect.height()); will happen in the switch fallthrough for MoveUp.
        rect.moveTop(rect.top() - d->viewport->height() + 2 * rect.height());
        if (rect.top() < rect.height())
            rect.moveTop(rect.height());
        Q_FALLTHROUGH();
    case MovePrevious:
    case MoveUp:
        while (intersectVector.isEmpty()) {
            rect.translate(0, -rect.height());
            if (rect.bottom() <= 0) {
#ifdef QT_KEYPAD_NAVIGATION
                if (QApplication::keypadNavigationEnabled()) {
                    int row = d->batchStartRow() - 1;
                    while (row >= 0 && d->isHiddenOrDisabled(row))
                        --row;
                    if (row >= 0)
                        return d->model->index(row, d->column, d->root);
                }
#endif
                return current;
            }
            if (rect.top() < 0)
                rect.setTop(0);
            intersectVector = d->intersectingSet(rect);
            d->removeCurrentAndDisabled(&intersectVector, current);
        }
        return d->closestIndex(initialRect, intersectVector);
    case MovePageDown:
        // move current by (visibileRowCount - 1) items.
        // rect.translate(0, rect.height()); will happen in the switch fallthrough for MoveDown.
        rect.moveTop(rect.top() + d->viewport->height() - 2 * rect.height());
        if (rect.bottom() > contents.height() - rect.height())
            rect.moveBottom(contents.height() - rect.height());
        Q_FALLTHROUGH();
    case MoveNext:
    case MoveDown:
        while (intersectVector.isEmpty()) {
            rect.translate(0, rect.height());
            if (rect.top() >= contents.height()) {
#ifdef QT_KEYPAD_NAVIGATION
                if (QApplication::keypadNavigationEnabled()) {
                    int rowCount = d->model->rowCount(d->root);
                    int row = 0;
                    while (row < rowCount && d->isHiddenOrDisabled(row))
                        ++row;
                    if (row < rowCount)
                        return d->model->index(row, d->column, d->root);
                }
#endif
                return current;
            }
            if (rect.bottom() > contents.height())
                rect.setBottom(contents.height());
            intersectVector = d->intersectingSet(rect);
            d->removeCurrentAndDisabled(&intersectVector, current);
        }
        return d->closestIndex(initialRect, intersectVector);
    case MoveHome:
        return d->model->index(0, d->column, d->root);
    case MoveEnd:
        return d->model->index(d->batchStartRow() - 1, d->column, d->root);}

    return current;
}

/*!
    Returns the rectangle of the item at position \a index in the
    model. The rectangle is in contents coordinates.

    \sa visualRect()
*/
QRect QListView::rectForIndex(const QModelIndex &index) const
{
    return d_func()->rectForIndex(index);
}

/*!
    \since 4.1

    Sets the contents position of the item at \a index in the model to the given
    \a position.
    If the list view's movement mode is Static or its view mode is ListView,
    this function will have no effect.
*/
void QListView::setPositionForIndex(const QPoint &position, const QModelIndex &index)
{
    Q_D(QListView);
    if (d->movement == Static
        || !d->isIndexValid(index)
        || index.parent() != d->root
        || index.column() != d->column)
        return;

    d->executePostedLayout();
    d->commonListView->setPositionForIndex(position, index);
}

/*!
  \reimp
*/
void QListView::setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags command)
{
    Q_D(QListView);
    if (!d->selectionModel)
        return;

    // if we are wrapping, we can only selecte inside the contents rectangle
    int w = qMax(d->contentsSize().width(), d->viewport->width());
    int h = qMax(d->contentsSize().height(), d->viewport->height());
    if (d->wrap && !QRect(0, 0, w, h).intersects(rect))
        return;

    QItemSelection selection;

    if (rect.width() == 1 && rect.height() == 1) {
        const QVector<QModelIndex> intersectVector = d->intersectingSet(rect.translated(horizontalOffset(), verticalOffset()));
        QModelIndex tl;
        if (!intersectVector.isEmpty())
            tl = intersectVector.last(); // special case for mouse press; only select the top item
        if (tl.isValid() && d->isIndexEnabled(tl))
            selection.select(tl, tl);
    } else {
        if (state() == DragSelectingState) { // visual selection mode (rubberband selection)
            selection = d->selection(rect.translated(horizontalOffset(), verticalOffset()));
        } else { // logical selection mode (key and mouse click selection)
            QModelIndex tl, br;
            // get the first item
            const QRect topLeft(rect.left() + horizontalOffset(), rect.top() + verticalOffset(), 1, 1);
            QVector<QModelIndex> intersectVector = d->intersectingSet(topLeft);
            if (!intersectVector.isEmpty())
                tl = intersectVector.last();
            // get the last item
            const QRect bottomRight(rect.right() + horizontalOffset(), rect.bottom() + verticalOffset(), 1, 1);
            intersectVector = d->intersectingSet(bottomRight);
            if (!intersectVector.isEmpty())
                br = intersectVector.last();

            // get the ranges
            if (tl.isValid() && br.isValid()
                && d->isIndexEnabled(tl)
                && d->isIndexEnabled(br)) {
                QRect first = rectForIndex(tl);
                QRect last = rectForIndex(br);
                QRect middle;
                if (d->flow == LeftToRight) {
                    QRect &top = first;
                    QRect &bottom = last;
                    // if bottom is above top, swap them
                    if (top.center().y() > bottom.center().y()) {
                        QRect tmp = top;
                        top = bottom;
                        bottom = tmp;
                    }
                    // if the rect are on differnet lines, expand
                    if (top.top() != bottom.top()) {
                        // top rectangle
                        if (isRightToLeft())
                            top.setLeft(0);
                        else
                            top.setRight(contentsSize().width());
                        // bottom rectangle
                        if (isRightToLeft())
                            bottom.setRight(contentsSize().width());
                        else
                            bottom.setLeft(0);
                    } else if (top.left() > bottom.right()) {
                        if (isRightToLeft())
                            bottom.setLeft(top.right());
                        else
                            bottom.setRight(top.left());
                    } else {
                        if (isRightToLeft())
                            top.setLeft(bottom.right());
                        else
                            top.setRight(bottom.left());
                    }
                    // middle rectangle
                    if (top.bottom() < bottom.top()) {
                        if (gridSize().isValid() && !gridSize().isNull())
                            middle.setTop(top.top() + gridSize().height());
                        else
                            middle.setTop(top.bottom() + 1);
                        middle.setLeft(qMin(top.left(), bottom.left()));
                        middle.setBottom(bottom.top() - 1);
                        middle.setRight(qMax(top.right(), bottom.right()));
                    }
                } else {    // TopToBottom
                    QRect &left = first;
                    QRect &right = last;
                    if (left.center().x() > right.center().x())
                        qSwap(left, right);

                    int ch = contentsSize().height();
                    if (left.left() != right.left()) {
                        // left rectangle
                        if (isRightToLeft())
                            left.setTop(0);
                        else
                            left.setBottom(ch);

                        // top rectangle
                        if (isRightToLeft())
                            right.setBottom(ch);
                        else
                            right.setTop(0);
                        // only set middle if the
                        middle.setTop(0);
                        middle.setBottom(ch);
                        if (gridSize().isValid() && !gridSize().isNull())
                            middle.setLeft(left.left() + gridSize().width());
                        else
                            middle.setLeft(left.right() + 1);
                        middle.setRight(right.left() - 1);
                    } else if (left.bottom() < right.top()) {
                        left.setBottom(right.top() - 1);
                    } else {
                        right.setBottom(left.top() - 1);
                    }
                }

                // do the selections
                QItemSelection topSelection = d->selection(first);
                QItemSelection middleSelection = d->selection(middle);
                QItemSelection bottomSelection = d->selection(last);
                // merge
                selection.merge(topSelection, QItemSelectionModel::Select);
                selection.merge(middleSelection, QItemSelectionModel::Select);
                selection.merge(bottomSelection, QItemSelectionModel::Select);
            }
        }
    }

    d->selectionModel->select(selection, command);
}

/*!
  \reimp

  Since 4.7, the returned region only contains rectangles intersecting
  (or included in) the viewport.
*/
QRegion QListView::visualRegionForSelection(const QItemSelection &selection) const
{
    Q_D(const QListView);
    // ### NOTE: this is a potential bottleneck in non-static mode
    int c = d->column;
    QRegion selectionRegion;
    const QRect &viewportRect = d->viewport->rect();
    for (const auto &elem : selection) {
        if (!elem.isValid())
            continue;
        QModelIndex parent = elem.topLeft().parent();
        //we only display the children of the root in a listview
        //we're not interested in the other model indexes
        if (parent != d->root)
            continue;
        int t = elem.topLeft().row();
        int b = elem.bottomRight().row();
        if (d->viewMode == IconMode || d->isWrapping()) { // in non-static mode, we have to go through all selected items
            for (int r = t; r <= b; ++r) {
                const QRect &rect = visualRect(d->model->index(r, c, parent));
                if (viewportRect.intersects(rect))
                    selectionRegion += rect;
            }
        } else { // in static mode, we can optimize a bit
            while (t <= b && d->isHidden(t)) ++t;
            while (b >= t && d->isHidden(b)) --b;
            const QModelIndex top = d->model->index(t, c, parent);
            const QModelIndex bottom = d->model->index(b, c, parent);
            QRect rect(visualRect(top).topLeft(),
                       visualRect(bottom).bottomRight());
            if (viewportRect.intersects(rect))
                selectionRegion += rect;
        }
    }

    return selectionRegion;
}

/*!
  \reimp
*/
QModelIndexList QListView::selectedIndexes() const
{
    Q_D(const QListView);
    if (!d->selectionModel)
        return QModelIndexList();

    QModelIndexList viewSelected = d->selectionModel->selectedIndexes();
    auto ignorable = [this, d](const QModelIndex &index) {
        return index.column() != d->column || index.parent() != d->root || isIndexHidden(index);
    };
    viewSelected.erase(std::remove_if(viewSelected.begin(), viewSelected.end(), ignorable),
                       viewSelected.end());
    return viewSelected;
}

/*!
    \internal

    Layout the items according to the flow and wrapping properties.
*/
void QListView::doItemsLayout()
{
    Q_D(QListView);
    // showing the scroll bars will trigger a resize event,
    // so we set the state to expanding to avoid
    // triggering another layout
    QAbstractItemView::State oldState = state();
    setState(ExpandingState);
    if (d->model->columnCount(d->root) > 0) { // no columns means no contents
        d->resetBatchStartRow();
        if (layoutMode() == SinglePass)
            d->doItemsLayout(d->model->rowCount(d->root)); // layout everything
        else if (!d->batchLayoutTimer.isActive()) {
            if (!d->doItemsLayout(d->batchSize)) // layout is done
                d->batchLayoutTimer.start(0, this); // do a new batch as fast as possible
        }
    }
    QAbstractItemView::doItemsLayout();
    setState(oldState);        // restoring the oldState
}

/*!
  \reimp
*/
void QListView::updateGeometries()
{
    Q_D(QListView);
    if (geometry().isEmpty() || d->model->rowCount(d->root) <= 0 || d->model->columnCount(d->root) <= 0) {
        horizontalScrollBar()->setRange(0, 0);
        verticalScrollBar()->setRange(0, 0);
    } else {
        QModelIndex index = d->model->index(0, d->column, d->root);
        QStyleOptionViewItem option = d->viewOptionsV1();
        QSize step = d->itemSize(option, index);
        d->commonListView->updateHorizontalScrollBar(step);
        d->commonListView->updateVerticalScrollBar(step);
    }

    QAbstractItemView::updateGeometries();

    // if the scroll bars are turned off, we resize the contents to the viewport
    if (d->movement == Static && !d->isWrapping()) {
        d->layoutChildren(); // we need the viewport size to be updated
        if (d->flow == TopToBottom) {
            if (horizontalScrollBarPolicy() == Qt::ScrollBarAlwaysOff) {
                d->setContentsSize(viewport()->width(), contentsSize().height());
                horizontalScrollBar()->setRange(0, 0); // we see all the contents anyway
            }
        } else { // LeftToRight
            if (verticalScrollBarPolicy() == Qt::ScrollBarAlwaysOff) {
                d->setContentsSize(contentsSize().width(), viewport()->height());
                verticalScrollBar()->setRange(0, 0); // we see all the contents anyway
            }
        }
    }

}

/*!
  \reimp
*/
bool QListView::isIndexHidden(const QModelIndex &index) const
{
    Q_D(const QListView);
    return (d->isHidden(index.row())
            && (index.parent() == d->root)
            && index.column() == d->column);
}

/*!
    \property QListView::modelColumn
    \brief the column in the model that is visible

    By default, this property contains 0, indicating that the first
    column in the model will be shown.
*/
void QListView::setModelColumn(int column)
{
    Q_D(QListView);
    if (column < 0 || column >= d->model->columnCount(d->root))
        return;
    d->column = column;
    d->doDelayedItemsLayout();
}

int QListView::modelColumn() const
{
    Q_D(const QListView);
    return d->column;
}

/*!
    \property QListView::uniformItemSizes
    \brief whether all items in the listview have the same size
    \since 4.1

    This property should only be set to true if it is guaranteed that all items
    in the view have the same size. This enables the view to do some
    optimizations for performance purposes.

    By default, this property is \c false.
*/
void QListView::setUniformItemSizes(bool enable)
{
    Q_D(QListView);
    d->uniformItemSizes = enable;
}

bool QListView::uniformItemSizes() const
{
    Q_D(const QListView);
    return d->uniformItemSizes;
}

/*!
    \property QListView::wordWrap
    \brief the item text word-wrapping policy
    \since 4.2

    If this property is \c true then the item text is wrapped where
    necessary at word-breaks; otherwise it is not wrapped at all.
    This property is \c false by default.

    Please note that even if wrapping is enabled, the cell will not be
    expanded to make room for the text. It will print ellipsis for
    text that cannot be shown, according to the view's
    \l{QAbstractItemView::}{textElideMode}.
*/
void QListView::setWordWrap(bool on)
{
    Q_D(QListView);
    if (d->wrapItemText == on)
        return;
    d->wrapItemText = on;
    d->doDelayedItemsLayout();
}

bool QListView::wordWrap() const
{
    Q_D(const QListView);
    return d->wrapItemText;
}

/*!
    \property QListView::selectionRectVisible
    \brief if the selection rectangle should be visible
    \since 4.3

    If this property is \c true then the selection rectangle is visible;
    otherwise it will be hidden.

    \note The selection rectangle will only be visible if the selection mode
    is in a mode where more than one item can be selected; i.e., it will not
    draw a selection rectangle if the selection mode is
    QAbstractItemView::SingleSelection.

    By default, this property is \c false.
*/
void QListView::setSelectionRectVisible(bool show)
{
    Q_D(QListView);
    d->modeProperties |= uint(QListViewPrivate::SelectionRectVisible);
    d->setSelectionRectVisible(show);
}

bool QListView::isSelectionRectVisible() const
{
    Q_D(const QListView);
    return d->isSelectionRectVisible();
}

/*!
    \reimp
*/
bool QListView::event(QEvent *e)
{
    return QAbstractItemView::event(e);
}

/*
 * private object implementation
 */

QListViewPrivate::QListViewPrivate()
    : QAbstractItemViewPrivate(),
      commonListView(0),
      wrap(false),
      space(0),
      flow(QListView::TopToBottom),
      movement(QListView::Static),
      resizeMode(QListView::Fixed),
      layoutMode(QListView::SinglePass),
      viewMode(QListView::ListMode),
      modeProperties(0),
      column(0),
      uniformItemSizes(false),
      batchSize(100),
      showElasticBand(false)
{
}

QListViewPrivate::~QListViewPrivate()
{
    delete commonListView;
}

void QListViewPrivate::clear()
{
    // initialization of data structs
    cachedItemSize = QSize();
    commonListView->clear();
}

void QListViewPrivate::prepareItemsLayout()
{
    Q_Q(QListView);
    clear();

    //take the size as if there were scrollbar in order to prevent scrollbar to blink
    layoutBounds = QRect(QPoint(), q->maximumViewportSize());

    int frameAroundContents = 0;
    if (q->style()->styleHint(QStyle::SH_ScrollView_FrameOnlyAroundContents))
        frameAroundContents = q->style()->pixelMetric(QStyle::PM_DefaultFrameWidth) * 2;

    // maximumViewportSize() already takes scrollbar into account if policy is
    // Qt::ScrollBarAlwaysOn but scrollbar extent must be deduced if policy
    // is Qt::ScrollBarAsNeeded
    int verticalMargin = vbarpolicy==Qt::ScrollBarAsNeeded
        ? q->style()->pixelMetric(QStyle::PM_ScrollBarExtent, 0, vbar) + frameAroundContents
        : 0;
    int horizontalMargin =  hbarpolicy==Qt::ScrollBarAsNeeded
        ? q->style()->pixelMetric(QStyle::PM_ScrollBarExtent, 0, hbar) + frameAroundContents
        : 0;

    layoutBounds.adjust(0, 0, -verticalMargin, -horizontalMargin);

    int rowCount = model->columnCount(root) <= 0 ? 0 : model->rowCount(root);
    commonListView->setRowCount(rowCount);
}

/*!
  \internal
*/
bool QListViewPrivate::doItemsLayout(int delta)
{
    int max = model->rowCount(root) - 1;
    int first = batchStartRow();
    int last = qMin(first + delta - 1, max);

    if (first == 0) {
        layoutChildren(); // make sure the viewport has the right size
        prepareItemsLayout();
    }

    if (max < 0 || last < first) {
        return true; // nothing to do
    }

    QListViewLayoutInfo info;
    info.bounds = layoutBounds;
    info.grid = gridSize();
    info.spacing = (info.grid.isValid() ? 0 : spacing());
    info.first = first;
    info.last = last;
    info.wrap = isWrapping();
    info.flow = flow;
    info.max = max;

    return commonListView->doBatchedItemLayout(info, max);
}

QListViewItem QListViewPrivate::indexToListViewItem(const QModelIndex &index) const
{
    if (!index.isValid() || isHidden(index.row()))
        return QListViewItem();

    return commonListView->indexToListViewItem(index);
}

QRect QListViewPrivate::mapToViewport(const QRect &rect, bool extend) const
{
    Q_Q(const QListView);
    if (!rect.isValid())
        return rect;

    QRect result = extend ? commonListView->mapToViewport(rect) : rect;
    int dx = -q->horizontalOffset();
    int dy = -q->verticalOffset();
    return result.adjusted(dx, dy, dx, dy);
}

QModelIndex QListViewPrivate::closestIndex(const QRect &target,
                                           const QVector<QModelIndex> &candidates) const
{
    int distance = 0;
    int shortest = INT_MAX;
    QModelIndex closest;
    QVector<QModelIndex>::const_iterator it = candidates.begin();

    for (; it != candidates.end(); ++it) {
        if (!(*it).isValid())
            continue;

        const QRect indexRect = indexToListViewItem(*it).rect();

        //if the center x (or y) position of an item is included in the rect of the other item,
        //we define the distance between them as the difference in x (or y) of their respective center.
        // Otherwise, we use the nahattan  length between the 2 items
        if ((target.center().x() >= indexRect.x() && target.center().x() < indexRect.right())
            || (indexRect.center().x() >= target.x() && indexRect.center().x() < target.right())) {
                //one item's center is at the vertical of the other
                distance = qAbs(indexRect.center().y() - target.center().y());
        } else if ((target.center().y() >= indexRect.y() && target.center().y() < indexRect.bottom())
            || (indexRect.center().y() >= target.y() && indexRect.center().y() < target.bottom())) {
                //one item's center is at the vertical of the other
                distance = qAbs(indexRect.center().x() - target.center().x());
        } else {
            distance = (indexRect.center() - target.center()).manhattanLength();
        }
        if (distance < shortest) {
            shortest = distance;
            closest = *it;
        }
    }
    return closest;
}

QSize QListViewPrivate::itemSize(const QStyleOptionViewItem &option, const QModelIndex &index) const
{
    if (!uniformItemSizes) {
        const QAbstractItemDelegate *delegate = delegateForIndex(index);
        return delegate ? delegate->sizeHint(option, index) : QSize();
    }
    if (!cachedItemSize.isValid()) { // the last item is probaly the largest, so we use its size
        int row = model->rowCount(root) - 1;
        QModelIndex sample = model->index(row, column, root);
        const QAbstractItemDelegate *delegate = delegateForIndex(sample);
        cachedItemSize = delegate ? delegate->sizeHint(option, sample) : QSize();
    }
    return cachedItemSize;
}

QItemSelection QListViewPrivate::selection(const QRect &rect) const
{
    QItemSelection selection;
    QModelIndex tl, br;
    const QVector<QModelIndex> intersectVector = intersectingSet(rect);
    QVector<QModelIndex>::const_iterator it = intersectVector.begin();
    for (; it != intersectVector.end(); ++it) {
        if (!tl.isValid() && !br.isValid()) {
            tl = br = *it;
        } else if ((*it).row() == (tl.row() - 1)) {
            tl = *it; // expand current range
        } else if ((*it).row() == (br.row() + 1)) {
            br = (*it); // expand current range
        } else {
            selection.select(tl, br); // select current range
            tl = br = *it; // start new range
        }
    }

    if (tl.isValid() && br.isValid())
        selection.select(tl, br);
    else if (tl.isValid())
        selection.select(tl, tl);
    else if (br.isValid())
        selection.select(br, br);

    return selection;
}

#ifndef QT_NO_DRAGANDDROP
QAbstractItemView::DropIndicatorPosition QListViewPrivate::position(const QPoint &pos, const QRect &rect, const QModelIndex &idx) const
{
    if (viewMode == QListView::ListMode && flow == QListView::LeftToRight)
        return static_cast<QListModeViewBase *>(commonListView)->position(pos, rect, idx);
    else
        return QAbstractItemViewPrivate::position(pos, rect, idx);
}

bool QListViewPrivate::dropOn(QDropEvent *event, int *dropRow, int *dropCol, QModelIndex *dropIndex)
{
    if (viewMode == QListView::ListMode && flow == QListView::LeftToRight)
        return static_cast<QListModeViewBase *>(commonListView)->dropOn(event, dropRow, dropCol, dropIndex);
    else
        return QAbstractItemViewPrivate::dropOn(event, dropRow, dropCol, dropIndex);
}
#endif

void QListViewPrivate::removeCurrentAndDisabled(QVector<QModelIndex> *indexes, const QModelIndex &current) const
{
    auto isCurrentOrDisabled = [=](const QModelIndex &index) {
        return !isIndexEnabled(index) || index == current;
    };
    indexes->erase(std::remove_if(indexes->begin(), indexes->end(),
                                  isCurrentOrDisabled),
                   indexes->end());
}

/*
 * Common ListView Implementation
*/

void QCommonListViewBase::appendHiddenRow(int row)
{
    dd->hiddenRows.insert(dd->model->index(row, 0, qq->rootIndex()));
}

void QCommonListViewBase::removeHiddenRow(int row)
{
    dd->hiddenRows.remove(dd->model->index(row, 0, qq->rootIndex()));
}

#ifndef QT_NO_DRAGANDDROP
void QCommonListViewBase::paintDragDrop(QPainter *painter)
{
    // FIXME: Until the we can provide a proper drop indicator
    // in IconMode, it makes no sense to show it
    dd->paintDropIndicator(painter);
}
#endif

QSize QListModeViewBase::viewportSize(const QAbstractItemView *v)
{
    return v->contentsRect().marginsRemoved(v->viewportMargins()).size();
}

void QCommonListViewBase::updateHorizontalScrollBar(const QSize &step)
{
    horizontalScrollBar()->d_func()->itemviewChangeSingleStep(step.width() + spacing());
    horizontalScrollBar()->setPageStep(viewport()->width());

    // If both scroll bars are set to auto, we might end up in a situation with enough space
    // for the actual content. But still one of the scroll bars will become enabled due to
    // the other one using the space. The other one will become invisible in the same cycle.
    // -> Infinite loop, QTBUG-39902
    const bool bothScrollBarsAuto = qq->verticalScrollBarPolicy() == Qt::ScrollBarAsNeeded &&
                                    qq->horizontalScrollBarPolicy() == Qt::ScrollBarAsNeeded;

    const QSize viewportSize = QListModeViewBase::viewportSize(qq);

    bool verticalWantsToShow = contentsSize.height() > viewportSize.height();
    bool horizontalWantsToShow;
    if (verticalWantsToShow)
        horizontalWantsToShow = contentsSize.width() > viewportSize.width() - qq->verticalScrollBar()->width();
    else
        horizontalWantsToShow = contentsSize.width() > viewportSize.width();

    if (bothScrollBarsAuto && !horizontalWantsToShow) {
        // break the infinite loop described above by setting the range to 0, 0.
        // QAbstractScrollArea will then hide the scroll bar for us
        horizontalScrollBar()->setRange(0, 0);
    } else {
        horizontalScrollBar()->setRange(0, contentsSize.width() - viewport()->width());
    }
}

void QCommonListViewBase::updateVerticalScrollBar(const QSize &step)
{
    verticalScrollBar()->d_func()->itemviewChangeSingleStep(step.height() + spacing());
    verticalScrollBar()->setPageStep(viewport()->height());

    // If both scroll bars are set to auto, we might end up in a situation with enough space
    // for the actual content. But still one of the scroll bars will become enabled due to
    // the other one using the space. The other one will become invisible in the same cycle.
    // -> Infinite loop, QTBUG-39902
    const bool bothScrollBarsAuto = qq->verticalScrollBarPolicy() == Qt::ScrollBarAsNeeded &&
                                    qq->horizontalScrollBarPolicy() == Qt::ScrollBarAsNeeded;

    const QSize viewportSize = QListModeViewBase::viewportSize(qq);

    bool horizontalWantsToShow = contentsSize.width() > viewportSize.width();
    bool verticalWantsToShow;
    if (horizontalWantsToShow)
        verticalWantsToShow = contentsSize.height() > viewportSize.height() - qq->horizontalScrollBar()->height();
    else
        verticalWantsToShow = contentsSize.height() > viewportSize.height();

    if (bothScrollBarsAuto && !verticalWantsToShow) {
        // break the infinite loop described above by setting the range to 0, 0.
        // QAbstractScrollArea will then hide the scroll bar for us
        verticalScrollBar()->setRange(0, 0);
    } else {
        verticalScrollBar()->setRange(0, contentsSize.height() - viewport()->height());
    }
}

void QCommonListViewBase::scrollContentsBy(int dx, int dy, bool /*scrollElasticBand*/)
{
    dd->scrollContentsBy(isRightToLeft() ? -dx : dx, dy);
}

int QCommonListViewBase::verticalScrollToValue(int /*index*/, QListView::ScrollHint hint,
                                          bool above, bool below, const QRect &area, const QRect &rect) const
{
    int verticalValue = verticalScrollBar()->value();
    QRect adjusted = rect.adjusted(-spacing(), -spacing(), spacing(), spacing());
    if (hint == QListView::PositionAtTop || above)
        verticalValue += adjusted.top();
    else if (hint == QListView::PositionAtBottom || below)
        verticalValue += qMin(adjusted.top(), adjusted.bottom() - area.height() + 1);
    else if (hint == QListView::PositionAtCenter)
        verticalValue += adjusted.top() - ((area.height() - adjusted.height()) / 2);
    return verticalValue;
}

int QCommonListViewBase::horizontalOffset() const
{
    return (isRightToLeft() ? horizontalScrollBar()->maximum() - horizontalScrollBar()->value() : horizontalScrollBar()->value());
}

int QCommonListViewBase::horizontalScrollToValue(const int /*index*/, QListView::ScrollHint hint,
                                            bool leftOf, bool rightOf, const QRect &area, const QRect &rect) const
{
    int horizontalValue = horizontalScrollBar()->value();
    if (isRightToLeft()) {
        if (hint == QListView::PositionAtCenter) {
            horizontalValue += ((area.width() - rect.width()) / 2) - rect.left();
        } else {
            if (leftOf)
                horizontalValue -= rect.left();
            else if (rightOf)
                horizontalValue += qMin(rect.left(), area.width() - rect.right());
        }
    } else {
        if (hint == QListView::PositionAtCenter) {
            horizontalValue += rect.left() - ((area.width()- rect.width()) / 2);
        } else {
            if (leftOf)
                horizontalValue += rect.left();
            else if (rightOf)
                horizontalValue += qMin(rect.left(), rect.right() - area.width());
        }
    }
    return horizontalValue;
}

/*
 * ListMode ListView Implementation
*/
QListModeViewBase::QListModeViewBase(QListView *q, QListViewPrivate *d)
    : QCommonListViewBase(q, d)
{
#if QT_CONFIG(draganddrop)
    dd->defaultDropAction = Qt::CopyAction;
#endif
}

#ifndef QT_NO_DRAGANDDROP
QAbstractItemView::DropIndicatorPosition QListModeViewBase::position(const QPoint &pos, const QRect &rect, const QModelIndex &index) const
{
    QAbstractItemView::DropIndicatorPosition r = QAbstractItemView::OnViewport;
    if (!dd->overwrite) {
        const int margin = 2;
        if (pos.x() - rect.left() < margin) {
            r = QAbstractItemView::AboveItem;   // Visually, on the left
        } else if (rect.right() - pos.x() < margin) {
            r = QAbstractItemView::BelowItem;   // Visually, on the right
        } else if (rect.contains(pos, true)) {
            r = QAbstractItemView::OnItem;
        }
    } else {
        QRect touchingRect = rect;
        touchingRect.adjust(-1, -1, 1, 1);
        if (touchingRect.contains(pos, false)) {
            r = QAbstractItemView::OnItem;
        }
    }

    if (r == QAbstractItemView::OnItem && (!(dd->model->flags(index) & Qt::ItemIsDropEnabled)))
        r = pos.x() < rect.center().x() ? QAbstractItemView::AboveItem : QAbstractItemView::BelowItem;

    return r;
}

void QListModeViewBase::dragMoveEvent(QDragMoveEvent *event)
{
    if (qq->dragDropMode() == QAbstractItemView::InternalMove
        && (event->source() != qq || !(event->possibleActions() & Qt::MoveAction)))
        return;

    // ignore by default
    event->ignore();

    // can't use indexAt, doesn't account for spacing.
    QPoint p = event->pos();
    QRect rect(p.x() + horizontalOffset(), p.y() + verticalOffset(), 1, 1);
    rect.adjust(-dd->spacing(), -dd->spacing(), dd->spacing(), dd->spacing());
    const QVector<QModelIndex> intersectVector = dd->intersectingSet(rect);
    QModelIndex index = intersectVector.count() > 0
                        ? intersectVector.last() : QModelIndex();
    dd->hover = index;
    if (!dd->droppingOnItself(event, index)
        && dd->canDrop(event)) {

        if (index.isValid() && dd->showDropIndicator) {
            QRect rect = qq->visualRect(index);
            dd->dropIndicatorPosition = position(event->pos(), rect, index);
            // if spacing, should try to draw between items, not just next to item.
            switch (dd->dropIndicatorPosition) {
            case QAbstractItemView::AboveItem:
                if (dd->isIndexDropEnabled(index.parent())) {
                    dd->dropIndicatorRect = QRect(rect.left()-dd->spacing(), rect.top(), 0, rect.height());
                    event->accept();
                } else {
                    dd->dropIndicatorRect = QRect();
                }
                break;
            case QAbstractItemView::BelowItem:
                if (dd->isIndexDropEnabled(index.parent())) {
                    dd->dropIndicatorRect = QRect(rect.right()+dd->spacing(), rect.top(), 0, rect.height());
                    event->accept();
                } else {
                    dd->dropIndicatorRect = QRect();
                }
                break;
            case QAbstractItemView::OnItem:
                if (dd->isIndexDropEnabled(index)) {
                    dd->dropIndicatorRect = rect;
                    event->accept();
                } else {
                    dd->dropIndicatorRect = QRect();
                }
                break;
            case QAbstractItemView::OnViewport:
                dd->dropIndicatorRect = QRect();
                if (dd->isIndexDropEnabled(qq->rootIndex())) {
                    event->accept(); // allow dropping in empty areas
                }
                break;
            }
        } else {
            dd->dropIndicatorRect = QRect();
            dd->dropIndicatorPosition = QAbstractItemView::OnViewport;
            if (dd->isIndexDropEnabled(qq->rootIndex())) {
                event->accept(); // allow dropping in empty areas
            }
        }
        dd->viewport->update();
    } // can drop

    if (dd->shouldAutoScroll(event->pos()))
        qq->startAutoScroll();
}

/*!
    If the event hasn't already been accepted, determines the index to drop on.

    if (row == -1 && col == -1)
        // append to this drop index
    else
        // place at row, col in drop index

    If it returns \c true a drop can be done, and dropRow, dropCol and dropIndex reflects the position of the drop.
    \internal
  */
bool QListModeViewBase::dropOn(QDropEvent *event, int *dropRow, int *dropCol, QModelIndex *dropIndex)
{
    if (event->isAccepted())
        return false;

    QModelIndex index;
    if (dd->viewport->rect().contains(event->pos())) {
        // can't use indexAt, doesn't account for spacing.
        QPoint p = event->pos();
        QRect rect(p.x() + horizontalOffset(), p.y() + verticalOffset(), 1, 1);
        rect.adjust(-dd->spacing(), -dd->spacing(), dd->spacing(), dd->spacing());
        const QVector<QModelIndex> intersectVector = dd->intersectingSet(rect);
        index = intersectVector.count() > 0
            ? intersectVector.last() : QModelIndex();
        if (!index.isValid())
            index = dd->root;
    }

    // If we are allowed to do the drop
    if (dd->model->supportedDropActions() & event->dropAction()) {
        int row = -1;
        int col = -1;
        if (index != dd->root) {
            dd->dropIndicatorPosition = position(event->pos(), qq->visualRect(index), index);
            switch (dd->dropIndicatorPosition) {
            case QAbstractItemView::AboveItem:
                row = index.row();
                col = index.column();
                index = index.parent();
                break;
            case QAbstractItemView::BelowItem:
                row = index.row() + 1;
                col = index.column();
                index = index.parent();
                break;
            case QAbstractItemView::OnItem:
            case QAbstractItemView::OnViewport:
                break;
            }
        } else {
            dd->dropIndicatorPosition = QAbstractItemView::OnViewport;
        }
        *dropIndex = index;
        *dropRow = row;
        *dropCol = col;
        if (!dd->droppingOnItself(event, index))
            return true;
    }
    return false;
}

#endif //QT_NO_DRAGANDDROP

void QListModeViewBase::updateVerticalScrollBar(const QSize &step)
{
    if (verticalScrollMode() == QAbstractItemView::ScrollPerItem
        && ((flow() == QListView::TopToBottom && !isWrapping())
        || (flow() == QListView::LeftToRight && isWrapping()))) {
            const int steps = (flow() == QListView::TopToBottom ? scrollValueMap : segmentPositions).count() - 1;
            if (steps > 0) {
                const int pageSteps = perItemScrollingPageSteps(viewport()->height(), contentsSize.height(), isWrapping());
                verticalScrollBar()->setSingleStep(1);
                verticalScrollBar()->setPageStep(pageSteps);
                verticalScrollBar()->setRange(0, steps - pageSteps);
            } else {
                verticalScrollBar()->setRange(0, 0);
            }
            // } else if (vertical && d->isWrapping() && d->movement == Static) {
            // ### wrapped scrolling in flow direction
    } else {
        QCommonListViewBase::updateVerticalScrollBar(step);
    }
}

void QListModeViewBase::updateHorizontalScrollBar(const QSize &step)
{
    if (horizontalScrollMode() == QAbstractItemView::ScrollPerItem
        && ((flow() == QListView::TopToBottom && isWrapping())
        || (flow() == QListView::LeftToRight && !isWrapping()))) {
            int steps = (flow() == QListView::TopToBottom ? segmentPositions : scrollValueMap).count() - 1;
            if (steps > 0) {
                const int pageSteps = perItemScrollingPageSteps(viewport()->width(), contentsSize.width(), isWrapping());
                horizontalScrollBar()->setSingleStep(1);
                horizontalScrollBar()->setPageStep(pageSteps);
                horizontalScrollBar()->setRange(0, steps - pageSteps);
            } else {
                horizontalScrollBar()->setRange(0, 0);
            }
    } else {
        QCommonListViewBase::updateHorizontalScrollBar(step);
    }
}

int QListModeViewBase::verticalScrollToValue(int index, QListView::ScrollHint hint,
                                          bool above, bool below, const QRect &area, const QRect &rect) const
{
    if (verticalScrollMode() == QAbstractItemView::ScrollPerItem) {
        int value;
        if (scrollValueMap.isEmpty()) {
            value = 0;
        } else {
            int scrollBarValue = verticalScrollBar()->value();
            int numHidden = 0;
            for (int i = 0; i < flowPositions.count() - 1 && i <= scrollBarValue; ++i)
                if (isHidden(i))
                    ++numHidden;
            value = qBound(0, scrollValueMap.at(verticalScrollBar()->value()) - numHidden, flowPositions.count() - 1);
        }
        if (above)
            hint = QListView::PositionAtTop;
        else if (below)
            hint = QListView::PositionAtBottom;
        if (hint == QListView::EnsureVisible)
            return value;

        return perItemScrollToValue(index, value, area.height(), hint, Qt::Vertical, isWrapping(), rect.height());
    }

    return QCommonListViewBase::verticalScrollToValue(index, hint, above, below, area, rect);
}

int QListModeViewBase::horizontalOffset() const
{
    if (horizontalScrollMode() == QAbstractItemView::ScrollPerItem) {
        if (isWrapping()) {
            if (flow() == QListView::TopToBottom && !segmentPositions.isEmpty()) {
                const int max = segmentPositions.count() - 1;
                int currentValue = qBound(0, horizontalScrollBar()->value(), max);
                int position = segmentPositions.at(currentValue);
                int maximumValue = qBound(0, horizontalScrollBar()->maximum(), max);
                int maximum = segmentPositions.at(maximumValue);
                return (isRightToLeft() ? maximum - position : position);
            }
        } else if (flow() == QListView::LeftToRight && !flowPositions.isEmpty()) {
            int position = flowPositions.at(scrollValueMap.at(horizontalScrollBar()->value()));
            int maximum = flowPositions.at(scrollValueMap.at(horizontalScrollBar()->maximum()));
            return (isRightToLeft() ? maximum - position : position);
        }
    }
    return QCommonListViewBase::horizontalOffset();
}

int QListModeViewBase::verticalOffset() const
{
    if (verticalScrollMode() == QAbstractItemView::ScrollPerItem) {
        if (isWrapping()) {
            if (flow() == QListView::LeftToRight && !segmentPositions.isEmpty()) {
                int value = verticalScrollBar()->value();
                if (value >= segmentPositions.count())
                    return 0;
                return segmentPositions.at(value) - spacing();
            }
        } else if (flow() == QListView::TopToBottom && !flowPositions.isEmpty()) {
            int value = verticalScrollBar()->value();
            if (value > scrollValueMap.count())
                return 0;
            return flowPositions.at(scrollValueMap.at(value)) - spacing();
        }
    }
    return QCommonListViewBase::verticalOffset();
}

int QListModeViewBase::horizontalScrollToValue(int index, QListView::ScrollHint hint,
                                            bool leftOf, bool rightOf, const QRect &area, const QRect &rect) const
{
    if (horizontalScrollMode() != QAbstractItemView::ScrollPerItem)
        return QCommonListViewBase::horizontalScrollToValue(index, hint, leftOf, rightOf, area, rect);

    int value;
    if (scrollValueMap.isEmpty())
        value = 0;
    else
        value = qBound(0, scrollValueMap.at(horizontalScrollBar()->value()), flowPositions.count() - 1);
    if (leftOf)
        hint = QListView::PositionAtTop;
    else if (rightOf)
        hint = QListView::PositionAtBottom;
    if (hint == QListView::EnsureVisible)
        return value;

    return perItemScrollToValue(index, value, area.width(), hint, Qt::Horizontal, isWrapping(), rect.width());
}

void QListModeViewBase::scrollContentsBy(int dx, int dy, bool scrollElasticBand)
{
    // ### reorder this logic
    const int verticalValue = verticalScrollBar()->value();
    const int horizontalValue = horizontalScrollBar()->value();
    const bool vertical = (verticalScrollMode() == QAbstractItemView::ScrollPerItem);
    const bool horizontal = (horizontalScrollMode() == QAbstractItemView::ScrollPerItem);

    if (isWrapping()) {
        if (segmentPositions.isEmpty())
            return;
        const int max = segmentPositions.count() - 1;
        if (horizontal && flow() == QListView::TopToBottom && dx != 0) {
            int currentValue = qBound(0, horizontalValue, max);
            int previousValue = qBound(0, currentValue + dx, max);
            int currentCoordinate = segmentPositions.at(currentValue) - spacing();
            int previousCoordinate = segmentPositions.at(previousValue) - spacing();
            dx = previousCoordinate - currentCoordinate;
        } else if (vertical && flow() == QListView::LeftToRight && dy != 0) {
            int currentValue = qBound(0, verticalValue, max);
            int previousValue = qBound(0, currentValue + dy, max);
            int currentCoordinate = segmentPositions.at(currentValue) - spacing();
            int previousCoordinate = segmentPositions.at(previousValue) - spacing();
            dy = previousCoordinate - currentCoordinate;
        }
    } else {
        if (flowPositions.isEmpty())
            return;
        const int max = scrollValueMap.count() - 1;
        if (vertical && flow() == QListView::TopToBottom && dy != 0) {
            int currentValue = qBound(0, verticalValue, max);
            int previousValue = qBound(0, currentValue + dy, max);
            int currentCoordinate = flowPositions.at(scrollValueMap.at(currentValue));
            int previousCoordinate = flowPositions.at(scrollValueMap.at(previousValue));
            dy = previousCoordinate - currentCoordinate;
        } else if (horizontal && flow() == QListView::LeftToRight && dx != 0) {
            int currentValue = qBound(0, horizontalValue, max);
            int previousValue = qBound(0, currentValue + dx, max);
            int currentCoordinate = flowPositions.at(scrollValueMap.at(currentValue));
            int previousCoordinate = flowPositions.at(scrollValueMap.at(previousValue));
            dx = previousCoordinate - currentCoordinate;
        }
    }
    QCommonListViewBase::scrollContentsBy(dx, dy, scrollElasticBand);
}

bool QListModeViewBase::doBatchedItemLayout(const QListViewLayoutInfo &info, int max)
{
    doStaticLayout(info);
    return batchStartRow > max; // returning true stops items layout
}

QListViewItem QListModeViewBase::indexToListViewItem(const QModelIndex &index) const
{
    if (flowPositions.isEmpty()
        || segmentPositions.isEmpty()
        || index.row() >= flowPositions.count() - 1)
        return QListViewItem();

    const int segment = qBinarySearch<int>(segmentStartRows, index.row(),
                                           0, segmentStartRows.count() - 1);


    QStyleOptionViewItem options = viewOptions();
    options.rect.setSize(contentsSize);
    QSize size = (uniformItemSizes() && cachedItemSize().isValid())
                 ? cachedItemSize() : itemSize(options, index);

    QPoint pos;
    if (flow() == QListView::LeftToRight) {
        pos.setX(flowPositions.at(index.row()));
        pos.setY(segmentPositions.at(segment));
    } else { // TopToBottom
        pos.setY(flowPositions.at(index.row()));
        pos.setX(segmentPositions.at(segment));
        if (isWrapping()) { // make the items as wide as the segment
            int right = (segment + 1 >= segmentPositions.count()
                     ? contentsSize.width()
                     : segmentPositions.at(segment + 1));
            size.setWidth(right - pos.x());
        } else { // make the items as wide as the viewport
            size.setWidth(qMax(size.width(), viewport()->width() - 2 * spacing()));
        }
    }

    return QListViewItem(QRect(pos, size), index.row());
}

QPoint QListModeViewBase::initStaticLayout(const QListViewLayoutInfo &info)
{
    int x, y;
    if (info.first == 0) {
        flowPositions.clear();
        segmentPositions.clear();
        segmentStartRows.clear();
        segmentExtents.clear();
        scrollValueMap.clear();
        x = info.bounds.left() + info.spacing;
        y = info.bounds.top() + info.spacing;
        segmentPositions.append(info.flow == QListView::LeftToRight ? y : x);
        segmentStartRows.append(0);
    } else if (info.wrap) {
        if (info.flow == QListView::LeftToRight) {
            x = batchSavedPosition;
            y = segmentPositions.constLast();
        } else { // flow == QListView::TopToBottom
            x = segmentPositions.constLast();
            y = batchSavedPosition;
        }
    } else { // not first and not wrap
        if (info.flow == QListView::LeftToRight) {
            x = batchSavedPosition;
            y = info.bounds.top() + info.spacing;
        } else { // flow == QListView::TopToBottom
            x = info.bounds.left() + info.spacing;
            y = batchSavedPosition;
        }
    }
    return QPoint(x, y);
}

/*!
  \internal
*/
void QListModeViewBase::doStaticLayout(const QListViewLayoutInfo &info)
{
    const bool useItemSize = !info.grid.isValid();
    const QPoint topLeft = initStaticLayout(info);
    QStyleOptionViewItem option = viewOptions();
    option.rect = info.bounds;
    option.rect.adjust(info.spacing, info.spacing, -info.spacing, -info.spacing);

    // The static layout data structures are as follows:
    // One vector contains the coordinate in the direction of layout flow.
    // Another vector contains the coordinates of the segments.
    // A third vector contains the index (model row) of the first item
    // of each segment.

    int segStartPosition;
    int segEndPosition;
    int deltaFlowPosition;
    int deltaSegPosition;
    int deltaSegHint;
    int flowPosition;
    int segPosition;

    if (info.flow == QListView::LeftToRight) {
        segStartPosition = info.bounds.left();
        segEndPosition = info.bounds.width();
        flowPosition = topLeft.x();
        segPosition = topLeft.y();
        deltaFlowPosition = info.grid.width(); // dx
        deltaSegPosition = useItemSize ? batchSavedDeltaSeg : info.grid.height(); // dy
        deltaSegHint = info.grid.height();
    } else { // flow == QListView::TopToBottom
        segStartPosition = info.bounds.top();
        segEndPosition = info.bounds.height();
        flowPosition = topLeft.y();
        segPosition = topLeft.x();
        deltaFlowPosition = info.grid.height(); // dy
        deltaSegPosition = useItemSize ? batchSavedDeltaSeg : info.grid.width(); // dx
        deltaSegHint = info.grid.width();
    }

    for (int row = info.first; row <= info.last; ++row) {
        if (isHidden(row)) { // ###
            flowPositions.append(flowPosition);
        } else {
            // if we are not using a grid, we need to find the deltas
            if (useItemSize) {
                QSize hint = itemSize(option, modelIndex(row));
                if (info.flow == QListView::LeftToRight) {
                    deltaFlowPosition = hint.width() + info.spacing;
                    deltaSegHint = hint.height() + info.spacing;
                } else { // TopToBottom
                    deltaFlowPosition = hint.height() + info.spacing;
                    deltaSegHint = hint.width() + info.spacing;
                }
            }
            // create new segment
            if (info.wrap && (flowPosition + deltaFlowPosition >= segEndPosition)) {
                segmentExtents.append(flowPosition);
                flowPosition = info.spacing + segStartPosition;
                segPosition += info.spacing + deltaSegPosition;
                segmentPositions.append(segPosition);
                segmentStartRows.append(row);
                deltaSegPosition = 0;
            }
            // save the flow position of this item
            scrollValueMap.append(flowPositions.count());
            flowPositions.append(flowPosition);
            // prepare for the next item
            deltaSegPosition = qMax(deltaSegHint, deltaSegPosition);
            flowPosition += info.spacing + deltaFlowPosition;
        }
    }
    // used when laying out next batch
    batchSavedPosition = flowPosition;
    batchSavedDeltaSeg = deltaSegPosition;
    batchStartRow = info.last + 1;
    if (info.last == info.max)
        flowPosition -= info.spacing; // remove extra spacing
    // set the contents size
    QRect rect = info.bounds;
    if (info.flow == QListView::LeftToRight) {
        rect.setRight(segmentPositions.count() == 1 ? flowPosition : info.bounds.right());
        rect.setBottom(segPosition + deltaSegPosition);
    } else { // TopToBottom
        rect.setRight(segPosition + deltaSegPosition);
        rect.setBottom(segmentPositions.count() == 1 ? flowPosition : info.bounds.bottom());
    }
    contentsSize = QSize(rect.right(), rect.bottom());
    // if it is the last batch, save the end of the segments
    if (info.last == info.max) {
        segmentExtents.append(flowPosition);
        scrollValueMap.append(flowPositions.count());
        flowPositions.append(flowPosition);
        segmentPositions.append(info.wrap ? segPosition + deltaSegPosition : INT_MAX);
    }
    // if the new items are visble, update the viewport
    QRect changedRect(topLeft, rect.bottomRight());
    if (clipRect().intersects(changedRect))
        viewport()->update();
}

/*!
  \internal
  Finds the set of items intersecting with \a area.
  In this function, itemsize is counted from topleft to the start of the next item.
*/
QVector<QModelIndex> QListModeViewBase::intersectingSet(const QRect &area) const
{
    QVector<QModelIndex> ret;
    int segStartPosition;
    int segEndPosition;
    int flowStartPosition;
    int flowEndPosition;
    if (flow() == QListView::LeftToRight) {
        segStartPosition = area.top();
        segEndPosition = area.bottom();
        flowStartPosition = area.left();
        flowEndPosition = area.right();
    } else {
        segStartPosition = area.left();
        segEndPosition = area.right();
        flowStartPosition = area.top();
        flowEndPosition = area.bottom();
    }
    if (segmentPositions.count() < 2 || flowPositions.isEmpty())
        return ret;
    // the last segment position is actually the edge of the last segment
    const int segLast = segmentPositions.count() - 2;
    int seg = qBinarySearch<int>(segmentPositions, segStartPosition, 0, segLast + 1);
    for (; seg <= segLast && segmentPositions.at(seg) <= segEndPosition; ++seg) {
        int first = segmentStartRows.at(seg);
        int last = (seg < segLast ? segmentStartRows.at(seg + 1) : batchStartRow) - 1;
        if (segmentExtents.at(seg) < flowStartPosition)
            continue;
        int row = qBinarySearch<int>(flowPositions, flowStartPosition, first, last);
        for (; row <= last && flowPositions.at(row) <= flowEndPosition; ++row) {
            if (isHidden(row))
                continue;
            QModelIndex index = modelIndex(row);
            if (index.isValid())
                ret += index;
#if 0 // for debugging
            else
                qWarning("intersectingSet: row %d was invalid", row);
#endif
        }
    }
    return ret;
}

void QListModeViewBase::dataChanged(const QModelIndex &, const QModelIndex &)
{
    dd->doDelayedItemsLayout();
}


QRect QListModeViewBase::mapToViewport(const QRect &rect) const
{
    if (isWrapping())
        return rect;
    // If the listview is in "listbox-mode", the items are as wide as the view.
    // But we don't shrink the items.
    QRect result = rect;
    if (flow() == QListView::TopToBottom) {
        result.setLeft(spacing());
        result.setWidth(qMax(rect.width(), qMax(contentsSize.width(), viewport()->width()) - 2 * spacing()));
    } else { // LeftToRight
        result.setTop(spacing());
        result.setHeight(qMax(rect.height(), qMax(contentsSize.height(), viewport()->height()) - 2 * spacing()));
    }
    return result;
}

int QListModeViewBase::perItemScrollingPageSteps(int length, int bounds, bool wrap) const
{
    QVector<int> positions;
    if (wrap)
        positions = segmentPositions;
    else if (!flowPositions.isEmpty()) {
        positions.reserve(scrollValueMap.size());
        foreach (int itemShown, scrollValueMap)
            positions.append(flowPositions.at(itemShown));
    }
    if (positions.isEmpty() || bounds <= length)
        return positions.count();
    if (uniformItemSizes()) {
        for (int i = 1; i < positions.count(); ++i)
            if (positions.at(i) > 0)
                return length / positions.at(i);
        return 0; // all items had height 0
    }
    int pageSteps = 0;
    int steps = positions.count() - 1;
    int max = qMax(length, bounds);
    int min = qMin(length, bounds);
    int pos = min - (max - positions.constLast());

    while (pos >= 0 && steps > 0) {
        pos -= (positions.at(steps) - positions.at(steps - 1));
        if (pos >= 0) //this item should be visible
            ++pageSteps;
        --steps;
    }

    // at this point we know that positions has at least one entry
    return qMax(pageSteps, 1);
}

int QListModeViewBase::perItemScrollToValue(int index, int scrollValue, int viewportSize,
                                                 QAbstractItemView::ScrollHint hint,
                                                 Qt::Orientation orientation, bool wrap, int itemExtent) const
{
    if (index < 0)
        return scrollValue;

    itemExtent += spacing();
    QVector<int> visibleFlowPositions;
    visibleFlowPositions.reserve(flowPositions.count() - 1);
    for (int i = 0; i < flowPositions.count() - 1; i++) { // flowPositions count is +1 larger than actual row count
        if (!isHidden(i))
            visibleFlowPositions.append(flowPositions.at(i));
    }

    if (!wrap) {
        int topIndex = index;
        const int bottomIndex = topIndex;
        const int bottomCoordinate = visibleFlowPositions.at(index);

        while (topIndex > 0 &&
               (bottomCoordinate - visibleFlowPositions.at(topIndex - 1) + itemExtent) <= (viewportSize)) {
            topIndex--;
        }

        const int itemCount = bottomIndex - topIndex + 1;
        switch (hint) {
        case QAbstractItemView::PositionAtTop:
            return index;
        case QAbstractItemView::PositionAtBottom:
            return index - itemCount + 1;
        case QAbstractItemView::PositionAtCenter:
            return index - (itemCount / 2);
        default:
            break;
        }
    } else { // wrapping
        Qt::Orientation flowOrientation = (flow() == QListView::LeftToRight
                                           ? Qt::Horizontal : Qt::Vertical);
        if (flowOrientation == orientation) { // scrolling in the "flow" direction
            // ### wrapped scrolling in the flow direction
            return visibleFlowPositions.at(index); // ### always pixel based for now
        } else if (!segmentStartRows.isEmpty()) { // we are scrolling in the "segment" direction
            int segment = qBinarySearch<int>(segmentStartRows, index, 0, segmentStartRows.count() - 1);
            int leftSegment = segment;
            const int rightSegment = leftSegment;
            const int bottomCoordinate = segmentPositions.at(segment);

            while (leftSegment > scrollValue &&
                (bottomCoordinate - segmentPositions.at(leftSegment-1) + itemExtent) <= (viewportSize)) {
                    leftSegment--;
            }

            const int segmentCount = rightSegment - leftSegment + 1;
            switch (hint) {
            case QAbstractItemView::PositionAtTop:
                return segment;
            case QAbstractItemView::PositionAtBottom:
                return segment - segmentCount + 1;
            case QAbstractItemView::PositionAtCenter:
                return segment - (segmentCount / 2);
            default:
                break;
            }
        }
    }
    return scrollValue;
}

void QListModeViewBase::clear()
{
    flowPositions.clear();
    segmentPositions.clear();
    segmentStartRows.clear();
    segmentExtents.clear();
    batchSavedPosition = 0;
    batchStartRow = 0;
    batchSavedDeltaSeg = 0;
}

/*
 * IconMode ListView Implementation
*/

void QIconModeViewBase::setPositionForIndex(const QPoint &position, const QModelIndex &index)
{
    if (index.row() >= items.count())
        return;
    const QSize oldContents = contentsSize;
    qq->update(index); // update old position
    moveItem(index.row(), position);
    qq->update(index); // update new position

    if (contentsSize != oldContents)
        dd->viewUpdateGeometries(); // update the scroll bars
}

void QIconModeViewBase::appendHiddenRow(int row)
{
    if (row >= 0 && row < items.count()) //remove item
        tree.removeLeaf(items.at(row).rect(), row);
    QCommonListViewBase::appendHiddenRow(row);
}

void QIconModeViewBase::removeHiddenRow(int row)
{
    QCommonListViewBase::removeHiddenRow(row);
    if (row >= 0 && row < items.count()) //insert item
        tree.insertLeaf(items.at(row).rect(), row);
}

#ifndef QT_NO_DRAGANDDROP
bool QIconModeViewBase::filterStartDrag(Qt::DropActions supportedActions)
{
    // This function does the same thing as in QAbstractItemView::startDrag(),
    // plus adding viewitems to the draggedItems list.
    // We need these items to draw the drag items
    QModelIndexList indexes = dd->selectionModel->selectedIndexes();
    if (indexes.count() > 0 ) {
        if (viewport()->acceptDrops()) {
            QModelIndexList::ConstIterator it = indexes.constBegin();
            for (; it != indexes.constEnd(); ++it)
                if (dd->model->flags(*it) & Qt::ItemIsDragEnabled
                    && (*it).column() == dd->column)
                    draggedItems.push_back(*it);
        }

        QRect rect;
        QPixmap pixmap = dd->renderToPixmap(indexes, &rect);
        rect.adjust(horizontalOffset(), verticalOffset(), 0, 0);
        QDrag *drag = new QDrag(qq);
        drag->setMimeData(dd->model->mimeData(indexes));
        drag->setPixmap(pixmap);
        drag->setHotSpot(dd->pressedPosition - rect.topLeft());
        Qt::DropAction action = drag->exec(supportedActions, dd->defaultDropAction);
        draggedItems.clear();
        if (action == Qt::MoveAction)
            dd->clearOrRemove();
    }
    return true;
}

bool QIconModeViewBase::filterDropEvent(QDropEvent *e)
{
    if (e->source() != qq)
        return false;

    const QSize contents = contentsSize;
    QPoint offset(horizontalOffset(), verticalOffset());
    QPoint end = e->pos() + offset;
    if (qq->acceptDrops()) {
        const Qt::ItemFlags dropableFlags = Qt::ItemIsDropEnabled|Qt::ItemIsEnabled;
        const QVector<QModelIndex> &dropIndices = intersectingSet(QRect(end, QSize(1, 1)));
        foreach (const QModelIndex &index, dropIndices)
            if ((index.flags() & dropableFlags) == dropableFlags)
                return false;
    }
    QPoint start = dd->pressedPosition;
    QPoint delta = (dd->movement == QListView::Snap ? snapToGrid(end) - snapToGrid(start) : end - start);
    const QList<QModelIndex> indexes = dd->selectionModel->selectedIndexes();
    for (const auto &index : indexes) {
        QRect rect = dd->rectForIndex(index);
        viewport()->update(dd->mapToViewport(rect, false));
        QPoint dest = rect.topLeft() + delta;
        if (qq->isRightToLeft())
            dest.setX(dd->flipX(dest.x()) - rect.width());
        moveItem(index.row(), dest);
        qq->update(index);
    }
    dd->stopAutoScroll();
    draggedItems.clear();
    dd->emitIndexesMoved(indexes);
    e->accept(); // we have handled the event
    // if the size has not grown, we need to check if it has shrinked
    if (contentsSize != contents) {
        if ((contentsSize.width() <= contents.width()
            || contentsSize.height() <= contents.height())) {
                updateContentsSize();
        }
        dd->viewUpdateGeometries();
    }
    return true;
}

bool QIconModeViewBase::filterDragLeaveEvent(QDragLeaveEvent *e)
{
    viewport()->update(draggedItemsRect()); // erase the area
    draggedItemsPos = QPoint(-1, -1); // don't draw the dragged items
    return QCommonListViewBase::filterDragLeaveEvent(e);
}

bool QIconModeViewBase::filterDragMoveEvent(QDragMoveEvent *e)
{
    if (e->source() != qq || !dd->canDrop(e))
        return false;

    // ignore by default
    e->ignore();
    // get old dragged items rect
    QRect itemsRect = this->itemsRect(draggedItems);
    viewport()->update(itemsRect.translated(draggedItemsDelta()));
    // update position
    draggedItemsPos = e->pos();
    // get new items rect
    viewport()->update(itemsRect.translated(draggedItemsDelta()));
    // set the item under the cursor to current
    QModelIndex index;
    if (movement() == QListView::Snap) {
        QRect rect(snapToGrid(e->pos() + offset()), gridSize());
        const QVector<QModelIndex> intersectVector = intersectingSet(rect);
        index = intersectVector.count() > 0 ? intersectVector.last() : QModelIndex();
    } else {
        index = qq->indexAt(e->pos());
    }
    // check if we allow drops here
    if (draggedItems.contains(index))
        e->accept(); // allow changing item position
    else if (dd->model->flags(index) & Qt::ItemIsDropEnabled)
        e->accept(); // allow dropping on dropenabled items
    else if (!index.isValid())
        e->accept(); // allow dropping in empty areas

    // the event was treated. do autoscrolling
    if (dd->shouldAutoScroll(e->pos()))
        dd->startAutoScroll();
    return true;
}
#endif // QT_NO_DRAGANDDROP

void QIconModeViewBase::setRowCount(int rowCount)
{
    tree.create(qMax(rowCount - hiddenCount(), 0));
}

void QIconModeViewBase::scrollContentsBy(int dx, int dy, bool scrollElasticBand)
{
    if (scrollElasticBand)
        dd->scrollElasticBandBy(isRightToLeft() ? -dx : dx, dy);

    QCommonListViewBase::scrollContentsBy(dx, dy, scrollElasticBand);
    if (!draggedItems.isEmpty())
        viewport()->update(draggedItemsRect().translated(dx, dy));
}

void QIconModeViewBase::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)
{
    if (column() >= topLeft.column() && column() <= bottomRight.column())  {
        QStyleOptionViewItem option = viewOptions();
        int bottom = qMin(items.count(), bottomRight.row() + 1);
        for (int row = topLeft.row(); row < bottom; ++row)
            items[row].resize(itemSize(option, modelIndex(row)));
    }
}

bool QIconModeViewBase::doBatchedItemLayout(const QListViewLayoutInfo &info, int max)
{
    if (info.last >= items.count()) {
        //first we create the items
        QStyleOptionViewItem option = viewOptions();
        for (int row = items.count(); row <= info.last; ++row) {
            QSize size = itemSize(option, modelIndex(row));
            QListViewItem item(QRect(0, 0, size.width(), size.height()), row); // default pos
            items.append(item);
        }
        doDynamicLayout(info);
    }
    return (batchStartRow > max); // done
}

QListViewItem QIconModeViewBase::indexToListViewItem(const QModelIndex &index) const
{
    if (index.isValid() && index.row() < items.count())
        return items.at(index.row());
    return QListViewItem();
}

void QIconModeViewBase::initBspTree(const QSize &contents)
{
    // remove all items from the tree
    int leafCount = tree.leafCount();
    for (int l = 0; l < leafCount; ++l)
        tree.leaf(l).clear();
    // we have to get the bounding rect of the items before we can initialize the tree
    QBspTree::Node::Type type = QBspTree::Node::Both; // 2D
    // simple heuristics to get better bsp
    if (contents.height() / contents.width() >= 3)
        type = QBspTree::Node::HorizontalPlane;
    else if (contents.width() / contents.height() >= 3)
        type = QBspTree::Node::VerticalPlane;
    // build tree for the bounding rect (not just the contents rect)
    tree.init(QRect(0, 0, contents.width(), contents.height()), type);
}

QPoint QIconModeViewBase::initDynamicLayout(const QListViewLayoutInfo &info)
{
    int x, y;
    if (info.first == 0) {
        x = info.bounds.x() + info.spacing;
        y = info.bounds.y() + info.spacing;
        items.reserve(rowCount() - hiddenCount());
    } else {
        int idx = info.first - 1;
        while (idx > 0 && !items.at(idx).isValid())
            --idx;
        const QListViewItem &item = items.at(idx);
        x = item.x;
        y = item.y;
        if (info.flow == QListView::LeftToRight)
            x += (info.grid.isValid() ? info.grid.width() : item.w) + info.spacing;
        else
            y += (info.grid.isValid() ? info.grid.height() : item.h) + info.spacing;
    }
    return QPoint(x, y);
}

/*!
  \internal
*/
void QIconModeViewBase::doDynamicLayout(const QListViewLayoutInfo &info)
{
    const bool useItemSize = !info.grid.isValid();
    const QPoint topLeft = initDynamicLayout(info);

    int segStartPosition;
    int segEndPosition;
    int deltaFlowPosition;
    int deltaSegPosition;
    int deltaSegHint;
    int flowPosition;
    int segPosition;

    if (info.flow == QListView::LeftToRight) {
        segStartPosition = info.bounds.left() + info.spacing;
        segEndPosition = info.bounds.right();
        deltaFlowPosition = info.grid.width(); // dx
        deltaSegPosition = (useItemSize ? batchSavedDeltaSeg : info.grid.height()); // dy
        deltaSegHint = info.grid.height();
        flowPosition = topLeft.x();
        segPosition = topLeft.y();
    } else { // flow == QListView::TopToBottom
        segStartPosition = info.bounds.top() + info.spacing;
        segEndPosition = info.bounds.bottom();
        deltaFlowPosition = info.grid.height(); // dy
        deltaSegPosition = (useItemSize ? batchSavedDeltaSeg : info.grid.width()); // dx
        deltaSegHint = info.grid.width();
        flowPosition = topLeft.y();
        segPosition = topLeft.x();
    }

    if (moved.count() != items.count())
        moved.resize(items.count());

    QRect rect(QPoint(), topLeft);
    QListViewItem *item = 0;
    for (int row = info.first; row <= info.last; ++row) {
        item = &items[row];
        if (isHidden(row)) {
            item->invalidate();
        } else {
            // if we are not using a grid, we need to find the deltas
            if (useItemSize) {
                if (info.flow == QListView::LeftToRight)
                    deltaFlowPosition = item->w + info.spacing;
                else
                    deltaFlowPosition = item->h + info.spacing;
            } else {
                item->w = qMin<int>(info.grid.width(), item->w);
                item->h = qMin<int>(info.grid.height(), item->h);
            }

            // create new segment
            if (info.wrap
                && flowPosition + deltaFlowPosition > segEndPosition
                && flowPosition > segStartPosition) {
                flowPosition = segStartPosition;
                segPosition += deltaSegPosition;
                if (useItemSize)
                    deltaSegPosition = 0;
            }
            // We must delay calculation of the seg adjustment, as this item
            // may have caused a wrap to occur
            if (useItemSize) {
                if (info.flow == QListView::LeftToRight)
                    deltaSegHint = item->h + info.spacing;
                else
                    deltaSegHint = item->w + info.spacing;
                deltaSegPosition = qMax(deltaSegPosition, deltaSegHint);
            }

            // set the position of the item
            // ### idealy we should have some sort of alignment hint for the item
            // ### (normally that would be a point between the icon and the text)
            if (!moved.testBit(row)) {
                if (info.flow == QListView::LeftToRight) {
                    if (useItemSize) {
                        item->x = flowPosition;
                        item->y = segPosition;
                    } else { // use grid
                        item->x = flowPosition + ((deltaFlowPosition - item->w) / 2);
                        item->y = segPosition;
                    }
                } else { // TopToBottom
                    if (useItemSize) {
                        item->y = flowPosition;
                        item->x = segPosition;
                    } else { // use grid
                        item->y = flowPosition + ((deltaFlowPosition - item->h) / 2);
                        item->x = segPosition;
                    }
                }
            }

            // let the contents contain the new item
            if (useItemSize)
                rect |= item->rect();
            else if (info.flow == QListView::LeftToRight)
                rect |= QRect(flowPosition, segPosition, deltaFlowPosition, deltaSegPosition);
            else // flow == TopToBottom
                rect |= QRect(segPosition, flowPosition, deltaSegPosition, deltaFlowPosition);

            // prepare for next item
            flowPosition += deltaFlowPosition; // current position + item width + gap
        }
    }
    batchSavedDeltaSeg = deltaSegPosition;
    batchStartRow = info.last + 1;
    bool done = (info.last >= rowCount() - 1);
    // resize the content area
    if (done || !info.bounds.contains(item->rect())) {
        contentsSize = rect.size();
        if (info.flow == QListView::LeftToRight)
            contentsSize.rheight() += info.spacing;
        else
            contentsSize.rwidth() += info.spacing;
    }
    if (rect.size().isEmpty())
        return;
    // resize tree
    int insertFrom = info.first;
    if (done || info.first == 0) {
        initBspTree(rect.size());
        insertFrom = 0;
    }
    // insert items in tree
    for (int row = insertFrom; row <= info.last; ++row)
        tree.insertLeaf(items.at(row).rect(), row);
    // if the new items are visble, update the viewport
    QRect changedRect(topLeft, rect.bottomRight());
    if (clipRect().intersects(changedRect))
        viewport()->update();
}

QVector<QModelIndex> QIconModeViewBase::intersectingSet(const QRect &area) const
{
    QIconModeViewBase *that = const_cast<QIconModeViewBase*>(this);
    QBspTree::Data data(static_cast<void*>(that));
    QVector<QModelIndex> res;
    that->interSectingVector = &res;
    that->tree.climbTree(area, &QIconModeViewBase::addLeaf, data);
    that->interSectingVector = 0;
    return res;
}

QRect QIconModeViewBase::itemsRect(const QVector<QModelIndex> &indexes) const
{
    QVector<QModelIndex>::const_iterator it = indexes.begin();
    QListViewItem item = indexToListViewItem(*it);
    QRect rect(item.x, item.y, item.w, item.h);
    for (; it != indexes.end(); ++it) {
        item = indexToListViewItem(*it);
        rect |= viewItemRect(item);
    }
    return rect;
}

int QIconModeViewBase::itemIndex(const QListViewItem &item) const
{
    if (!item.isValid())
        return -1;
    int i = item.indexHint;
    if (i < items.count()) {
        if (items.at(i) == item)
            return i;
    } else {
        i = items.count() - 1;
    }

    int j = i;
    int c = items.count();
    bool a = true;
    bool b = true;

    while (a || b) {
        if (a) {
            if (items.at(i) == item) {
                items.at(i).indexHint = i;
                return i;
            }
            a = ++i < c;
        }
        if (b) {
            if (items.at(j) == item) {
                items.at(j).indexHint = j;
                return j;
            }
            b = --j > -1;
        }
    }
    return -1;
}

void QIconModeViewBase::addLeaf(QVector<int> &leaf, const QRect &area,
                                   uint visited, QBspTree::Data data)
{
    QListViewItem *vi;
    QIconModeViewBase *_this = static_cast<QIconModeViewBase *>(data.ptr);
    for (int i = 0; i < leaf.count(); ++i) {
        int idx = leaf.at(i);
        if (idx < 0 || idx >= _this->items.count())
            continue;
        vi = &_this->items[idx];
        Q_ASSERT(vi);
        if (vi->isValid() && vi->rect().intersects(area) && vi->visited != visited) {
            QModelIndex index  = _this->dd->listViewItemToIndex(*vi);
            Q_ASSERT(index.isValid());
            _this->interSectingVector->append(index);
            vi->visited = visited;
        }
    }
}

void QIconModeViewBase::moveItem(int index, const QPoint &dest)
{
    // does not impact on the bintree itself or the contents rect
    QListViewItem *item = &items[index];
    QRect rect = item->rect();

    // move the item without removing it from the tree
    tree.removeLeaf(rect, index);
    item->move(dest);
    tree.insertLeaf(QRect(dest, rect.size()), index);

    // resize the contents area
    contentsSize = (QRect(QPoint(0, 0), contentsSize)|QRect(dest, rect.size())).size();

    // mark the item as moved
    if (moved.count() != items.count())
        moved.resize(items.count());
    moved.setBit(index, true);
}

QPoint QIconModeViewBase::snapToGrid(const QPoint &pos) const
{
    int x = pos.x() - (pos.x() % gridSize().width());
    int y = pos.y() - (pos.y() % gridSize().height());
    return QPoint(x, y);
}

QPoint QIconModeViewBase::draggedItemsDelta() const
{
    if (movement() == QListView::Snap) {
        QPoint snapdelta = QPoint((offset().x() % gridSize().width()),
                                  (offset().y() % gridSize().height()));
        return snapToGrid(draggedItemsPos + snapdelta) - snapToGrid(pressedPosition()) - snapdelta;
    }
    return draggedItemsPos - pressedPosition();
}

QRect QIconModeViewBase::draggedItemsRect() const
{
    QRect rect = itemsRect(draggedItems);
    rect.translate(draggedItemsDelta());
    return rect;
}

void QListViewPrivate::scrollElasticBandBy(int dx, int dy)
{
    if (dx > 0) // right
        elasticBand.moveRight(elasticBand.right() + dx);
    else if (dx < 0) // left
        elasticBand.moveLeft(elasticBand.left() - dx);
    if (dy > 0) // down
        elasticBand.moveBottom(elasticBand.bottom() + dy);
    else if (dy < 0) // up
        elasticBand.moveTop(elasticBand.top() - dy);
}

void QIconModeViewBase::clear()
{
    tree.destroy();
    items.clear();
    moved.clear();
    batchStartRow = 0;
    batchSavedDeltaSeg = 0;
}

void QIconModeViewBase::updateContentsSize()
{
    QRect bounding;
    for (int i = 0; i < items.count(); ++i)
        bounding |= items.at(i).rect();
    contentsSize = bounding.size();
}

/*!
  \reimp
*/
void QListView::currentChanged(const QModelIndex &current, const QModelIndex &previous)
{
#ifndef QT_NO_ACCESSIBILITY
    if (QAccessible::isActive()) {
        if (current.isValid()) {
            int entry = visualIndex(current);
            QAccessibleEvent event(this, QAccessible::Focus);
            event.setChild(entry);
            QAccessible::updateAccessibility(&event);
        }
    }
#endif
    QAbstractItemView::currentChanged(current, previous);
}

/*!
  \reimp
*/
void QListView::selectionChanged(const QItemSelection &selected,
                                 const QItemSelection &deselected)
{
#ifndef QT_NO_ACCESSIBILITY
    if (QAccessible::isActive()) {
        // ### does not work properly for selection ranges.
        QModelIndex sel = selected.indexes().value(0);
        if (sel.isValid()) {
            int entry = visualIndex(sel);
            QAccessibleEvent event(this, QAccessible::SelectionAdd);
            event.setChild(entry);
            QAccessible::updateAccessibility(&event);
        }
        QModelIndex desel = deselected.indexes().value(0);
        if (desel.isValid()) {
            int entry = visualIndex(desel);
            QAccessibleEvent event(this, QAccessible::SelectionRemove);
            event.setChild(entry);
            QAccessible::updateAccessibility(&event);
        }
    }
#endif
    QAbstractItemView::selectionChanged(selected, deselected);
}

int QListView::visualIndex(const QModelIndex &index) const
{
    Q_D(const QListView);
    d->executePostedLayout();
    QListViewItem itm = d->indexToListViewItem(index);
    int visualIndex = d->commonListView->itemIndex(itm);
    for (int row = 0; row <= index.row() && visualIndex >= 0; row++) {
        if (d->isHidden(row))
            visualIndex--;
    }
    return visualIndex;
}


/*!
    \since 5.2
    \reimp
*/
QSize QListView::viewportSizeHint() const
{
    return QAbstractItemView::viewportSizeHint();
}

QT_END_NAMESPACE

#include "moc_qlistview.cpp"

#endif // QT_NO_LISTVIEW