Ensure subfocus is not reset to 0 when hiding a panel.

When hiding any widget that is not a panel, it is correct to clear
subfocus. In case clearFocus() has been called, the result is that
focusItem() / focusWidget() points to 0, which is correct. Upon
reactivation, nothing gains input focus. When changing focus, the
following setSubFocus() call will ensure subfocus points to the new
widget.

When hiding a panel, however, it's essential that subfocus within
that panel is not cleared, otherwise, when re-showing the panel,
nothing will have focus, whereas the expected behavior is that focus
is restored to the last item that had focus, i.e., the focusItem()
a.k.a. subfocus widget.

Task-number: QTBUG-22256
Change-Id: I84d849a505764e074e1369fef923cef1ad5c0b1e
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/src/widgets/graphicsview/qgraphicsitem_p.h b/src/widgets/graphicsview/qgraphicsitem_p.h
index 18a7376337..830afa938c 100644
--- a/src/widgets/graphicsview/qgraphicsitem_p.h
+++ b/src/widgets/graphicsview/qgraphicsitem_p.h
@@ -279,7 +279,8 @@ public:
     void setTransformHelper(const QTransform &transform);
     void prependGraphicsTransform(QGraphicsTransform *t);
     void appendGraphicsTransform(QGraphicsTransform *t);
-    void setVisibleHelper(bool newVisible, bool explicitly, bool update = true);
+    void setVisibleHelper(bool newVisible, bool explicitly, bool update = true,
+                          bool hiddenByPanel = false);
     void setEnabledHelper(bool newEnabled, bool explicitly, bool update = true);
     bool discardUpdateRequest(bool ignoreVisibleBit = false,
                               bool ignoreDirtyBit = false, bool ignoreOpacity = false) const;
@@ -476,7 +477,7 @@ public:
     inline void markParentDirty(bool updateBoundingRect = false);
 
     void setFocusHelper(Qt::FocusReason focusReason, bool climb, bool focusFromHide);
-    void clearFocusHelper(bool giveFocusToParent);
+    void clearFocusHelper(bool giveFocusToParent, bool hiddenByParentPanel);
     void setSubFocus(QGraphicsItem *rootItem = 0, QGraphicsItem *stopItem = 0);
     void clearSubFocus(QGraphicsItem *rootItem = 0, QGraphicsItem *stopItem = 0);
     void resetFocusProxy();