QQuickTableView: use QMap instead of a QRect to keep track of loaded columns

TableView keeps track of which rows and columns that are loaded
at any point by using a QRect called "loadedTable". loadedTable
basically describes the top-left and bottom-right corner of the
table that has been loaded (which also is what ends up visible
on screen).

But now that we prepare for making it possible to hide rows
and columns, using just a QRect becomes to simple. A rectangle will
only tell what the edges of the table are, but not if any of the
rows and columns in-between are hidden and therefore not loaded.
So a QRect(0, 0, 10, 10) will give us the impression that we have
10 visible columns on screen, but in reality, we might have a
lot less.

This patch will change this to instead use two QMaps to record
loaded rows and columns. This will make it much more easy
to deal with hidden rows and columns in upcoming patches. We
use a QMap instead of a QHash/QSet to keep the list of columns and
rows sorted, since we frequently still need to know the edges of
the table, like before.

Change-Id: I45736485c67042403b095e73b5f2effa411281d0
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 76 insertions, 79 deletions

diff --git a/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp b/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
index a3b9aa4c03..d2ec9948c9 100644
--- a/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
+++ b/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
@@ -251,8 +251,9 @@ void tst_QQuickTableView::checkPreload()
     WAIT_UNTIL_POLISHED;
 
     if (reuseItems) {
-        QSize visibleTableSize = tableViewPrivate->loadedTable.size();
-        int expectedPoolSize = visibleTableSize.height() + visibleTableSize.width() + 1;
+        const int rowCount = tableViewPrivate->loadedRows.count();
+        const int columnCount = tableViewPrivate->loadedColumns.count();
+        const int expectedPoolSize = rowCount + columnCount + 1;
         QCOMPARE(tableViewPrivate->tableModel->poolSize(), expectedPoolSize);
     } else {
         QCOMPARE(tableViewPrivate->tableModel->poolSize(), 0);
@@ -321,10 +322,9 @@ void tst_QQuickTableView::checkColumnWidthWithoutProvider()
 
     WAIT_UNTIL_POLISHED;
 
-    QRect table = tableViewPrivate->loadedTable;
-    for (int column = table.left(); column <= table.right(); ++column) {
+    for (const int column : tableViewPrivate->loadedColumns.keys()) {
         const qreal expectedColumnWidth = tableViewPrivate->sizeHintForColumn(column);
-        for (int row = table.top(); row <= table.bottom(); ++row) {
+        for (const int row : tableViewPrivate->loadedRows.keys()) {
             const auto item = tableViewPrivate->loadedTableItem(QPoint(column, row))->item;
             QCOMPARE(item->width(), expectedColumnWidth);
         }
@@ -414,10 +414,9 @@ void tst_QQuickTableView::checkRowHeightWithoutProvider()
 
     WAIT_UNTIL_POLISHED;
 
-    QRect table = tableViewPrivate->loadedTable;
-    for (int row = table.top(); row <= table.bottom(); ++row) {
+    for (const int row : tableViewPrivate->loadedRows.keys()) {
         const qreal expectedRowHeight = tableViewPrivate->sizeHintForRow(row);
-        for (int column = table.left(); column <= table.right(); ++column) {
+        for (const int column : tableViewPrivate->loadedColumns.keys()) {
             const auto item = tableViewPrivate->loadedTableItem(QPoint(column, row))->item;
             QCOMPARE(item->height(), expectedRowHeight);
         }
@@ -565,8 +564,8 @@ void tst_QQuickTableView::checkContentWidthAndHeight()
 
     const int largeSizeCellCountInView = qCeil(tableView->width() / cellSizeLarge);
     const int columnCount = smallCellCount + largeSizeCellCountInView;
-    QCOMPARE(tableViewPrivate->loadedTable.left(), smallCellCount);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->leftColumn(), smallCellCount);
+    QCOMPARE(tableViewPrivate->rightColumn(), columnCount - 1);
 
     const qreal firstHalfLength = smallCellCount * cellSizeSmall;
     const qreal secondHalfOneScreenLength = largeSizeCellCountInView * cellSizeLarge;
@@ -618,17 +617,18 @@ void tst_QQuickTableView::checkPageFlicking()
     const int cellWidth = 100;
     const int cellHeight = 50;
     auto model = TestModelAsVariant(10000, 10000);
+    const auto &loadedRows = tableViewPrivate->loadedRows;
+    const auto &loadedColumns = tableViewPrivate->loadedColumns;
 
     tableView->setModel(model);
 
     WAIT_UNTIL_POLISHED;
 
     // Sanity check startup table
-    QRect tableRect = tableViewPrivate->loadedTable;
-    QCOMPARE(tableRect.x(), 0);
-    QCOMPARE(tableRect.y(), 0);
-    QCOMPARE(tableRect.width(), tableView->width() / cellWidth);
-    QCOMPARE(tableRect.height(), tableView->height() / cellHeight);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->leftColumn(), 0);
+    QCOMPARE(loadedRows.count(), tableView->height() / cellHeight);
+    QCOMPARE(loadedColumns.count(), tableView->width() / cellWidth);
 
     // Since all cells have the same size, the average row/column
     // size found by TableView should be exactly equal to this.
@@ -652,11 +652,10 @@ void tst_QQuickTableView::checkPageFlicking()
 
     WAIT_UNTIL_POLISHED;
 
-    tableRect = tableViewPrivate->loadedTable;
-    QCOMPARE(tableRect.x(), flickToColumn);
-    QCOMPARE(tableRect.y(), 0);
-    QCOMPARE(tableRect.width(), tableView->width() / cellWidth);
-    QCOMPARE(tableRect.height(), tableView->height() / cellHeight);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->leftColumn(), flickToColumn);
+    QCOMPARE(loadedColumns.count(), tableView->width() / cellWidth);
+    QCOMPARE(loadedRows.count(), tableView->height() / cellHeight);
 
     // Flick 5000 rows down as well. Since flicking down should only calculate a new row (but
     // keep the current column), we deliberatly change the average width to check that it's
@@ -675,11 +674,10 @@ void tst_QQuickTableView::checkPageFlicking()
 
     WAIT_UNTIL_POLISHED;
 
-    tableRect = tableViewPrivate->loadedTable;
-    QCOMPARE(tableRect.x(), flickToRow);
-    QCOMPARE(tableRect.y(), flickToColumn);
-    QCOMPARE(tableRect.width(), tableView->width() / cellWidth);
-    QCOMPARE(tableRect.height(), tableView->height() / cellHeight);
+    QCOMPARE(tableViewPrivate->topRow(), flickToColumn);
+    QCOMPARE(tableViewPrivate->leftColumn(), flickToRow);
+    QCOMPARE(loadedRows.count(), tableView->height() / cellHeight);
+    QCOMPARE(loadedColumns.count(), tableView->width() / cellWidth);
 }
 
 void tst_QQuickTableView::checkExplicitContentWidthAndHeight()
@@ -729,8 +727,8 @@ void tst_QQuickTableView::checkContentXY()
     // Check that we end up at the correct top-left cell:
     const qreal delegateWidth = tableViewPrivate->loadedItems.values().first()->item->width();
     const int expectedCellXY = qCeil(expectedXY / delegateWidth);
-    QCOMPARE(tableViewPrivate->loadedTable.left(), expectedCellXY);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), expectedCellXY);
+    QCOMPARE(tableViewPrivate->leftColumn(), expectedCellXY);
+    QCOMPARE(tableViewPrivate->topRow(), expectedCellXY);
 }
 
 void tst_QQuickTableView::noDelegate()
@@ -1004,7 +1002,8 @@ void tst_QQuickTableView::fillTableViewButNothingMore()
     auto const topLeftFxItem = tableViewPrivate->loadedTableItem(QPoint(0, 0));
     auto const topLeftItem = topLeftFxItem->item;
 
-    auto const bottomRightFxItem = tableViewPrivate->loadedTableItem(tableViewPrivate->loadedTable.bottomRight());
+    auto const bottomRightLoadedCell = QPoint(tableViewPrivate->rightColumn(), tableViewPrivate->bottomRow());
+    auto const bottomRightFxItem = tableViewPrivate->loadedTableItem(bottomRightLoadedCell);
     auto const bottomRightItem = bottomRightFxItem->item;
     const QPoint bottomRightCell = getContextRowAndColumn(bottomRightItem.data());
 
@@ -1182,15 +1181,13 @@ void tst_QQuickTableView::flick()
 
         WAIT_UNTIL_POLISHED;
 
-        const QRect loadedTable = tableViewPrivate->loadedTable;
+        const int expectedTableLeft = int(cellsToFlick - int((margins.left() + spacing.width()) / cellWidth));
+        const int expectedTableTop = int(cellsToFlick - int((margins.top() + spacing.height()) / cellHeight));
 
-        const int expectedTableLeft = cellsToFlick - int((margins.left() + spacing.width()) / cellWidth);
-        const int expectedTableTop = cellsToFlick - int((margins.top() + spacing.height()) / cellHeight);
-
-        QCOMPARE(loadedTable.left(), expectedTableLeft);
-        QCOMPARE(loadedTable.right(), expectedTableLeft + visualColumnCount);
-        QCOMPARE(loadedTable.top(), expectedTableTop);
-        QCOMPARE(loadedTable.bottom(), expectedTableTop + visualRowCount);
+        QCOMPARE(tableViewPrivate->leftColumn(), expectedTableLeft);
+        QCOMPARE(tableViewPrivate->rightColumn(), expectedTableLeft + visualColumnCount);
+        QCOMPARE(tableViewPrivate->topRow(), expectedTableTop);
+        QCOMPARE(tableViewPrivate->bottomRow(), expectedTableTop + visualRowCount);
     }
 }
 
@@ -1252,10 +1249,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->leftColumn(), 0);
+    QCOMPARE(tableViewPrivate->rightColumn(), 0);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->bottomRow(), rowCount - 1);
 
     // Flick table out of view right
     tableView->setContentX(tableWidth + outsideMargin);
@@ -1264,10 +1261,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->leftColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->rightColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->bottomRow(), rowCount - 1);
 
     // Flick table out of view on top
     tableView->setContentX(0);
@@ -1276,10 +1273,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), 0);
+    QCOMPARE(tableViewPrivate->leftColumn(), 0);
+    QCOMPARE(tableViewPrivate->rightColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->bottomRow(), 0);
 
     // Flick table out of view at the bottom
     tableView->setContentX(0);
@@ -1288,10 +1285,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), rowCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->leftColumn(), 0);
+    QCOMPARE(tableViewPrivate->rightColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->topRow(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->bottomRow(), rowCount - 1);
 
     // Flick table out of view left and top at the same time
     tableView->setContentX(-tableView->width() - outsideMargin);
@@ -1300,10 +1297,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), 0);
+    QCOMPARE(tableViewPrivate->leftColumn(), 0);
+    QCOMPARE(tableViewPrivate->rightColumn(), 0);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->bottomRow(), 0);
 
     // Flick table back to origo
     tableView->setContentX(0);
@@ -1312,10 +1309,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->leftColumn(), 0);
+    QCOMPARE(tableViewPrivate->rightColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->bottomRow(), rowCount - 1);
 
     // Flick table out of view right and bottom at the same time
     tableView->setContentX(tableWidth + outsideMargin);
@@ -1324,10 +1321,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), rowCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->leftColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->rightColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->topRow(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->bottomRow(), rowCount - 1);
 
     // Flick table back to origo
     tableView->setContentX(0);
@@ -1336,10 +1333,10 @@ void tst_QQuickTableView::flickOvershoot()
 
     WAIT_UNTIL_POLISHED;
 
-    QCOMPARE(tableViewPrivate->loadedTable.left(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.right(), columnCount - 1);
-    QCOMPARE(tableViewPrivate->loadedTable.top(), 0);
-    QCOMPARE(tableViewPrivate->loadedTable.bottom(), rowCount - 1);
+    QCOMPARE(tableViewPrivate->leftColumn(), 0);
+    QCOMPARE(tableViewPrivate->rightColumn(), columnCount - 1);
+    QCOMPARE(tableViewPrivate->topRow(), 0);
+    QCOMPARE(tableViewPrivate->bottomRow(), rowCount - 1);
 }
 
 void tst_QQuickTableView::checkRowColumnCount()
@@ -1353,6 +1350,8 @@ void tst_QQuickTableView::checkRowColumnCount()
     const qreal delegateWidth = 100;
     const qreal delegateHeight = 50;
     auto model = TestModelAsVariant(100, 100);
+    const auto &loadedRows = tableViewPrivate->loadedRows;
+    const auto &loadedColumns = tableViewPrivate->loadedColumns;
 
     tableView->setModel(model);
 
@@ -1360,17 +1359,15 @@ void tst_QQuickTableView::checkRowColumnCount()
 
     // We expect that the number of created items after start-up should match
     //the size of the visible table, pluss one extra preloaded row and column.
-    const QSize visibleTableSize = tableViewPrivate->loadedTable.size();
     const int qmlCountAfterInit = view->rootObject()->property(maxDelegateCountProp).toInt();
-    const int expectedCount = (visibleTableSize.width() + 1) * (visibleTableSize.height() + 1);
+    const int expectedCount = (loadedColumns.count() + 1) * (loadedRows.count() + 1);
     QCOMPARE(qmlCountAfterInit, expectedCount);
 
     // This test will keep track of the maximum number of delegate items TableView
     // had to show at any point while flicking (in countingtableview.qml). Because
     // of the geometries chosen for TableView and the delegate, only complete columns
     // will be shown at start-up.
-    const QRect loadedTable = tableViewPrivate->loadedTable;
-    QVERIFY(loadedTable.height() > loadedTable.width());
+    QVERIFY(loadedRows.count() > loadedColumns.count());
     QCOMPARE(tableViewPrivate->loadedTableOuterRect.width(), tableView->width());
     QCOMPARE(tableViewPrivate->loadedTableOuterRect.height(), tableView->height());
 
@@ -1619,8 +1616,8 @@ void tst_QQuickTableView::checkIfDelegatesAreReused()
         fxItem->item->setProperty("reusedCount", 0);
     }
 
-    const int visibleColumnCount = tableViewPrivate->loadedTable.width();
-    const int visibleRowCount = tableViewPrivate->loadedTable.height();
+    const int visibleColumnCount = tableViewPrivate->loadedColumns.count();
+    const int visibleRowCount = tableViewPrivate->loadedRows.count();
     const int delegateCountAfterInit = view->rootObject()->property(kDelegatesCreatedCountProp).toInt();
 
     for (int column = 1; column <= (visibleColumnCount * pageFlickCount); ++column) {
@@ -1687,7 +1684,7 @@ void tst_QQuickTableView::checkIfDelegatesAreReusedAsymmetricTableSize()
 
     // Since we have flicked half a delegate to the left, the number of visible
     // columns is now one more than the column count were when we started the test.
-    const int visibleColumnCount = tableViewPrivate->loadedTable.width();
+    const int visibleColumnCount = tableViewPrivate->loadedColumns.count();
     QCOMPARE(visibleColumnCount, columnCount + 1);
 
     // We expect no items to have been pooled so far
@@ -1887,7 +1884,7 @@ void tst_QQuickTableView::checkChangingModelFromDelegate()
 
     // We now expect two rows in the table, one more than initially
     QCOMPARE(tableViewPrivate->tableSize.height(), 2);
-    QCOMPARE(tableViewPrivate->loadedTable.height(), 2);
+    QCOMPARE(tableViewPrivate->loadedRows.count(), 2);
 
     // And since the QML code tried to add another row as well, we
     // expect rebuildScheduled to be true, and a polish event to be pending.
@@ -1897,7 +1894,7 @@ void tst_QQuickTableView::checkChangingModelFromDelegate()
 
     // After handling the polish event, we expect also the third row to now be added
     QCOMPARE(tableViewPrivate->tableSize.height(), 3);
-    QCOMPARE(tableViewPrivate->loadedTable.height(), 3);
+    QCOMPARE(tableViewPrivate->loadedRows.count(), 3);
 }
 
 void tst_QQuickTableView::checkRebuildViewportOnly()
@@ -1982,8 +1979,8 @@ void tst_QQuickTableView::checkTableviewInsideAsyncLoader()
     const qreal delegateHeight = 50;
     int expectedColumns = qCeil(tableView->width() / delegateWidth);
     int expectedRows = qCeil(tableView->height() / delegateHeight);
-    QCOMPARE(tableViewPrivate->loadedTable.width(), expectedColumns);
-    QCOMPARE(tableViewPrivate->loadedTable.height(), expectedRows);
+    QCOMPARE(tableViewPrivate->loadedColumns.count(), expectedColumns);
+    QCOMPARE(tableViewPrivate->loadedRows.count(), expectedRows);
 
     // Check that the loader was still in a loading state while TableView was creating
     // delegate items. If we delayed creating delegate items until we got the first