Auto expand of QTreeWidget does not work correctly if animated

The problem was that the internal state of the tree was not correctly
reset. Patch comes from the task.

Task-number: QTBUG-10850

3 files changed, 7 insertions, 5 deletions

diff --git a/src/gui/itemviews/qabstractitemview.cpp b/src/gui/itemviews/qabstractitemview.cpp
index 2501fcb..8729906 100644
--- a/src/gui/itemviews/qabstractitemview.cpp
+++ b/src/gui/itemviews/qabstractitemview.cpp
@@ -79,6 +79,7 @@ QAbstractItemViewPrivate::QAbstractItemViewPrivate()
         pressedAlreadySelected(false),
         viewportEnteredNeeded(false),
         state(QAbstractItemView::NoState),
+        stateBeforeAnimation(QAbstractItemView::NoState),
         editTriggers(QAbstractItemView::DoubleClicked|QAbstractItemView::EditKeyPressed),
         lastTrigger(QAbstractItemView::NoEditTriggers),
         tabKeyNavigation(false),
diff --git a/src/gui/itemviews/qabstractitemview_p.h b/src/gui/itemviews/qabstractitemview_p.h
index cadc1f7..368c8ad 100644
--- a/src/gui/itemviews/qabstractitemview_p.h
+++ b/src/gui/itemviews/qabstractitemview_p.h
@@ -367,6 +367,7 @@ public:
     bool viewportEnteredNeeded;
 
     QAbstractItemView::State state;
+    QAbstractItemView::State stateBeforeAnimation;
     QAbstractItemView::EditTriggers editTriggers;
     QAbstractItemView::EditTrigger lastTrigger;
 
diff --git a/src/gui/itemviews/qtreeview.cpp b/src/gui/itemviews/qtreeview.cpp
index e3d71c6..e44c9ab 100644
--- a/src/gui/itemviews/qtreeview.cpp
+++ b/src/gui/itemviews/qtreeview.cpp
@@ -2871,13 +2871,13 @@ void QTreeViewPrivate::expand(int item, bool emitSignal)
     if (emitSignal && animationsEnabled)
         prepareAnimatedOperation(item, QVariantAnimation::Forward);
 #endif //QT_NO_ANIMATION
-    QAbstractItemView::State oldState = state;
+    stateBeforeAnimation = state;
     q->setState(QAbstractItemView::ExpandingState);
     const QModelIndex index = viewItems.at(item).index;
     storeExpanded(index);
     viewItems[item].expanded = true;
     layout(item);
-    q->setState(oldState);
+    q->setState(stateBeforeAnimation);
 
     if (model->canFetchMore(index))
         model->fetchMore(index);
@@ -2946,7 +2946,7 @@ void QTreeViewPrivate::collapse(int item, bool emitSignal)
         prepareAnimatedOperation(item, QVariantAnimation::Backward);
 #endif //QT_NO_ANIMATION
 
-    QAbstractItemView::State oldState = state;
+    stateBeforeAnimation = state;
     q->setState(QAbstractItemView::CollapsingState);
     expandedIndexes.erase(it);
     viewItems[item].expanded = false;
@@ -2956,7 +2956,7 @@ void QTreeViewPrivate::collapse(int item, bool emitSignal)
         index = viewItems[index].parentItem;
     }
     removeViewItems(item + 1, total); // collapse
-    q->setState(oldState);
+    q->setState(stateBeforeAnimation);
 
     if (emitSignal) {
         emit q->collapsed(modelIndex);
@@ -3067,7 +3067,7 @@ QPixmap QTreeViewPrivate::renderTreeToPixmapForAnimation(const QRect &rect) cons
 void QTreeViewPrivate::_q_endAnimatedOperation()
 {
     Q_Q(QTreeView);
-    q->setState(QAbstractItemView::NoState);
+    q->setState(stateBeforeAnimation);
     q->updateGeometries();
     viewport->update();
 }