Introduce QGraphicsItem::ItemStopsFocusHandling flag

When set for an item, QGraphicsScene will skip focus handling for this item and
everything underneath it (including focus-out). Allows users to reimplement
custom focus handling.

Use case: touch devices that implement panning. Here, focus-in has to happen
only if no panning was triggered. Analogous, no focus-out should happen when
panning was detected.

Fixes the alternative proposal ("black holes for focus changes") of
QTBUG-16343: QGraphicsView doesn't support focus change on mouse release.

The previous test was only testing one scenario, which didn't give a good idea
whether the flag was actually working as intended.

Task-number: QTBUG-17505
Reviewed-by: Yoann Lopes
Reviewed-by: Jan-Arve Sæther

1 files changed, 8 insertions, 0 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index f463887..4e2d4e2 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -417,6 +417,11 @@
     click focus to items underneath when being clicked on. This flag
     allows you create a non-focusable item that can be clicked on without
     changing the focus. \endomit
+
+    \omitvalue ItemStopsFocusHandling \omit Same as
+    ItemStopsClickFocusPropagation, but also suppresses focus-out. This flag
+    allows you to completely take over focus handling.
+    This flag was introduced in Qt 4.7.
 */
 
 /*!
@@ -11549,6 +11554,9 @@ QDebug operator<<(QDebug debug, QGraphicsItem::GraphicsItemFlag flag)
     case QGraphicsItem::ItemStopsClickFocusPropagation:
         str = "ItemStopsClickFocusPropagation";
         break;
+    case QGraphicsItem::ItemStopsFocusHandling:
+        str = "ItemStopsFocusHandling";
+        break;
     }
     debug << str;
     return debug;