Make sure QtGraphicsListView::maximumOffset() only returns positive values. Auto-test included.

2 files changed, 82 insertions, 2 deletions

diff --git a/src/qgraphicslistview.cpp b/src/qgraphicslistview.cpp
index a2f1546..0de92b7 100644
--- a/src/qgraphicslistview.cpp
+++ b/src/qgraphicslistview.cpp
@@ -895,7 +895,7 @@ qreal QtGraphicsListView::maximumOffset() const
             content += size.height();
             max = qMax(max, size.height());
         }
-        return content - size().height();
+        return qMax<qreal>(content - size().height(), 0);
     } else { // Horizontal
         for (int index = 0; index < count; ++index) {
             initStyleOption(&option, index);
@@ -903,7 +903,7 @@ qreal QtGraphicsListView::maximumOffset() const
             content += size.width();
             max = qMax(max, size.width());
         }
-        return content - size().width();
+        return qMax<qreal>(content - size().width(), 0);
     }
 }
 
diff --git a/tests/qgraphicslistview/tst_qgraphicslistview.cpp b/tests/qgraphicslistview/tst_qgraphicslistview.cpp
index 4fa76aa..2b0e339 100644
--- a/tests/qgraphicslistview/tst_qgraphicslistview.cpp
+++ b/tests/qgraphicslistview/tst_qgraphicslistview.cpp
@@ -157,10 +157,90 @@ void tst_QtGraphicsListView::getSetCheck()
 
 void tst_QtGraphicsListView::maximumOffset_data()
 {
+    QTest::addColumn<int>("count");
+    QTest::addColumn<int>("orientation");
+    QTest::addColumn<QSizeF>("size");
+    QTest::addColumn<qreal>("maximumOffset");
+
+    QTest::newRow("no items, vertical, all visible")
+        << 0
+        << int(Qt::Vertical)
+        << QSizeF(100, 100)
+        << 0.;
+
+    QTest::newRow("one item, vertical, all visible")
+        << 5
+        << int(Qt::Vertical)
+        << QSizeF(100, 100)
+        << 0.;
+
+    QTest::newRow("five items, vertical, all visible")
+        << 5
+        << int(Qt::Vertical)
+        << QSizeF(100, 100)
+        << 0.;
+
+    QTest::newRow("six items, vertical")
+        << 6
+        << int(Qt::Vertical)
+        << QSizeF(100, 100)
+        << 20.;
+
+    QTest::newRow("ten items, vertical")
+        << 10
+        << int(Qt::Vertical)
+        << QSizeF(100, 100)
+        << 100.;
+
+    QTest::newRow("no items, horizontal, all visible")
+        << 0
+        << int(Qt::Horizontal)
+        << QSizeF(100, 100)
+        << 0.;
+
+    QTest::newRow("one item, horizontal, all visible")
+        << 5
+        << int(Qt::Horizontal)
+        << QSizeF(100, 100)
+        << 0.;
+
+    QTest::newRow("five items, horizontal, all visible")
+        << 5
+        << int(Qt::Horizontal)
+        << QSizeF(100, 100)
+        << 0.;
+
+    QTest::newRow("six items, horizontal")
+        << 6
+        << int(Qt::Horizontal)
+        << QSizeF(100, 100)
+        << 20.;
+
+    QTest::newRow("ten items, horizontal")
+        << 10
+        << int(Qt::Horizontal)
+        << QSizeF(100, 100)
+        << 100.;
 }
 
 void tst_QtGraphicsListView::maximumOffset()
 {
+    QFETCH(int, count);
+    QFETCH(int, orientation);
+    QFETCH(QSizeF, size);
+    QFETCH(qreal, maximumOffset);
+
+    QtListDefaultModel model;
+    for (int i = 0; i < count; ++i)
+        model.insertItem(i, new QtListDefaultItem());
+
+    view->setOrientation(static_cast<Qt::Orientation>(orientation));
+    view->setGeometry(QRectF(QPointF(0, 0), size));
+    view->setItemCreator(new QtGraphicsListViewItemCreator<GraphicsListViewItem>());
+    view->setModel(&model);
+    view->doLayout();
+
+    QCOMPARE(view->maximumOffset(), maximumOffset);
 }
 
 void tst_QtGraphicsListView::maximumFirstIndex_data()