Fix GridView scrolling due to currentIndex changes. Add tests.

2 files changed, 47 insertions, 6 deletions

diff --git a/src/declarative/graphicsitems/qmlgraphicsgridview.cpp b/src/declarative/graphicsitems/qmlgraphicsgridview.cpp
index 473f9e5..7e2d983 100644
--- a/src/declarative/graphicsitems/qmlgraphicsgridview.cpp
+++ b/src/declarative/graphicsitems/qmlgraphicsgridview.cpp
@@ -1302,12 +1302,21 @@ void QmlGraphicsGridView::trackedPositionChanged()
     if (!d->trackedItem)
         return;
     if (!isFlicking() && !d->moving && d->moveReason != QmlGraphicsGridViewPrivate::Mouse) {
-        if (d->trackedItem->rowPos() < d->position()) {
-            d->setPosition(d->trackedItem->rowPos());
-        } else if (d->trackedItem->endRowPos() > d->position() + d->size()) {
-            qreal pos = d->trackedItem->endRowPos() - d->size();
-            if (d->rowSize() > d->size())
-                pos = d->trackedItem->rowPos();
+        const qreal viewPos = d->position();
+        if (d->trackedItem->rowPos() < viewPos && d->currentItem->rowPos() < viewPos) {
+            d->setPosition(d->currentItem->rowPos() < d->trackedItem->rowPos() ? d->trackedItem->rowPos() : d->currentItem->rowPos());
+        } else if (d->trackedItem->endRowPos() > viewPos + d->size()
+                && d->currentItem->endRowPos() > viewPos + d->size()) {
+            qreal pos;
+            if (d->trackedItem->endRowPos() < d->currentItem->endRowPos()) {
+                pos = d->trackedItem->endRowPos() - d->size();
+                if (d->rowSize() > d->size())
+                    pos = d->trackedItem->rowPos();
+            } else {
+                pos = d->currentItem->endRowPos() - d->size();
+                if (d->rowSize() > d->size())
+                    pos = d->currentItem->rowPos();
+            }
             d->setPosition(pos);
         }
     }
diff --git a/tests/auto/declarative/qmlgraphicsgridview/tst_qmlgraphicsgridview.cpp b/tests/auto/declarative/qmlgraphicsgridview/tst_qmlgraphicsgridview.cpp
index 197191e..f31ea49 100644
--- a/tests/auto/declarative/qmlgraphicsgridview/tst_qmlgraphicsgridview.cpp
+++ b/tests/auto/declarative/qmlgraphicsgridview/tst_qmlgraphicsgridview.cpp
@@ -394,6 +394,9 @@ void tst_QmlGraphicsGridView::removed()
     // let transitions settle.
     QTest::qWait(300);
 
+    // Setting currentIndex above shouldn't cause view to scroll
+    QCOMPARE(gridview->viewportY(), 120.0);
+
     model.removeItem(1);
 
     // let transitions settle.
@@ -408,6 +411,14 @@ void tst_QmlGraphicsGridView::removed()
         QVERIFY(item->y() == (i/3)*60);
     }
 
+    // Remove currentIndex
+    QmlGraphicsItem *oldCurrent = gridview->currentItem();
+    model.removeItem(9);
+    QTest::qWait(500);
+
+    QCOMPARE(gridview->currentIndex(), 9);
+    QVERIFY(gridview->currentItem() != oldCurrent);
+
     gridview->setViewportY(0);
     // let transitions settle.
     QTest::qWait(300);
@@ -430,6 +441,27 @@ void tst_QmlGraphicsGridView::removed()
     model.removeItem(30);
     QVERIFY(gridview->currentIndex() == 31);
 
+    // remove current item beyond visible items.
+    gridview->setCurrentIndex(20);
+    QTest::qWait(500);
+    gridview->setViewportY(0);
+    model.removeItem(20);
+    QTest::qWait(500);
+
+    QCOMPARE(gridview->currentIndex(), 20);
+    QVERIFY(gridview->currentItem() != 0);
+
+    // remove item before current, but visible
+    gridview->setCurrentIndex(8);
+    QTest::qWait(500);
+    gridview->setViewportY(240);
+    oldCurrent = gridview->currentItem();
+    model.removeItem(6);
+    QTest::qWait(500);
+
+    QCOMPARE(gridview->currentIndex(), 7);
+    QVERIFY(gridview->currentItem() == oldCurrent);
+
     delete canvas;
 }