1 files changed, 96 insertions, 24 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index 7e155e1..c4ff7c6 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -325,6 +325,10 @@
     \value ItemAcceptsInputMethod The item supports input methods typically
     used for Asian languages.
     This flag was introduced in Qt 4.6.
+
+    \value ItemAutoDetectsFocusProxy The item will assign any child that
+    gains input focus as its focus proxy. See also focusProxy().
+    This flag was introduced in Qt 4.6.
 */
 
 /*!
@@ -908,12 +912,12 @@ void QGraphicsItemPrivate::setParentItemHelper(QGraphicsItem *newParent)
         scene->d_func()->index->itemChange(q, QGraphicsItem::ItemParentChange, newParentVariant);
     }
 
-    if (QGraphicsWidget *w = isWidget ? static_cast<QGraphicsWidget *>(q) : q->parentWidget()) {
-        // Update the child focus chain; when reparenting a widget that has a
+    QGraphicsItem *lastSubFocusItem = subFocusItem;
+    if (subFocusItem) {
+        // Update the child focus chain; when reparenting an item that has a
         // focus child, ensure that that focus child clears its focus child
         // chain from our parents before it's reparented.
-        if (QGraphicsWidget *focusChild = w->focusWidget())
-            focusChild->clearFocus();
+        subFocusItem->clearFocus();
     }
 
     // We anticipate geometry changes. If the item is deleted, it will be
@@ -1001,6 +1005,21 @@ void QGraphicsItemPrivate::setParentItemHelper(QGraphicsItem *newParent)
     resolveDepth(parent ? parent->d_ptr->depth : -1);
     dirtySceneTransform = 1;
 
+    // Restore the sub focus chain.
+    if (lastSubFocusItem)
+        lastSubFocusItem->d_ptr->setSubFocus();
+
+    // Auto-update focus proxy. The closest parent that detects
+    // focus proxies is updated as the proxy gains or loses focus.
+    QGraphicsItem *p = newParent;
+    while (p) {
+        if (p->d_ptr->flags & QGraphicsItem::ItemAutoDetectsFocusProxy) {
+            p->setFocusProxy(q);
+            break;
+        }
+        p = p->d_ptr->parent;
+    }
+
     // Deliver post-change notification
     q->itemChange(QGraphicsItem::ItemParentHasChanged, newParentVariant);
 
@@ -2463,33 +2482,45 @@ bool QGraphicsItem::hasFocus() const
     be passed into any focus event generated by this function; it is used to
     give an explanation of what caused the item to get focus.
 
-    Only items that set the ItemIsFocusable flag can accept keyboard focus.
+    Only enabled items that set the ItemIsFocusable flag can accept keyboard
+    focus.
 
-    If this item is not visible (i.e., isVisible() returns false), not
-    enabled, not associated with a scene, or if it already has input focus,
-    this function will do nothing.
+    If this item is not visible, or not associated with a scene, it will not
+    gain immediate input focus. However, it will be registered as the preferred
+    focus item for its subtree of items, should it later become visible.
 
     As a result of calling this function, this item will receive a focus in
     event with \a focusReason. If another item already has focus, that item
     will first receive a focus out event indicating that it has lost input
     focus.
 
-    \sa clearFocus(), hasFocus()
+    \sa clearFocus(), hasFocus(), focusItem()
 */
 void QGraphicsItem::setFocus(Qt::FocusReason focusReason)
 {
-    if (!d_ptr->scene || !isEnabled() || hasFocus() || !(d_ptr->flags & ItemIsFocusable))
+    // Disabled / unfocusable items cannot accept focus.
+    if (!isEnabled() || !(d_ptr->flags & QGraphicsItem::ItemIsFocusable))
+        return;
+
+    // Find focus proxy.
+    QGraphicsItem *f = this;
+    while (f->d_ptr->focusProxy)
+        f = f->d_ptr->focusProxy;
+
+    // Return if it already has focus.
+    if (d_ptr->scene && d_ptr->scene->focusItem() == f)
         return;
-    QGraphicsItem *item = this;
-    QGraphicsItem *f;
-    while ((f = item->d_ptr->focusProxy))
-        item = f;
-    if (item->isVisible()) {
-        // Visible items immediately gain focus from scene.
-        d_ptr->scene->d_func()->setFocusItemHelper(item, focusReason);
-    } else if (item->d_ptr->isWidget) {
-        // Just set up subfocus.
-        static_cast<QGraphicsWidget *>(item)->d_func()->setFocusWidget();
+
+    // Update the child focus chain.
+    d_ptr->setSubFocus();
+
+    // Update the scene's focus item.
+    if (d_ptr->scene) {
+        QGraphicsWidget *w = window();
+        if (!w || w->isActiveWindow()) {
+            // Visible items immediately gain focus from scene.
+            d_ptr->scene->d_func()->setFocusItemHelper(f, focusReason);
+        }
     }
 }
 
@@ -2508,10 +2539,8 @@ void QGraphicsItem::clearFocus()
 {
     if (!d_ptr->scene)
         return;
-    if (d_ptr->isWidget) {
-        // Invisible widget items with focus must explicitly clear subfocus.
-        static_cast<QGraphicsWidget *>(this)->d_func()->clearFocusWidget();
-    }
+    // Invisible items with focus must explicitly clear subfocus.
+    d_ptr->clearSubFocus();
     if (hasFocus()) {
         // If this item has the scene's input focus, clear it.
         d_ptr->scene->setFocusItem(0);
@@ -2579,6 +2608,18 @@ void QGraphicsItem::setFocusProxy(QGraphicsItem *item)
 }
 
 /*!
+    If this item, a child or descendant of this item currently has input
+    focus, this function will return a pointer to that item. If
+    no descendant has input focus, 0 is returned.
+
+    \sa QWidget::focusWidget()
+*/
+QGraphicsItem *QGraphicsItem::focusItem() const
+{
+    return d_ptr->subFocusItem;
+}
+
+/*!
     \since 4.4
     Grabs the mouse input.
 
@@ -4668,6 +4709,34 @@ void QGraphicsItemPrivate::ensureSceneTransform()
 
 /*!
     \internal
+*/
+void QGraphicsItemPrivate::setSubFocus()
+{
+    // Update focus child chain.
+    QGraphicsItem *item = q_ptr;
+    QGraphicsItem *parent = item;
+    bool hidden = !visible;
+    do {
+        parent->d_func()->subFocusItem = item;
+    } while (!parent->isWindow() && (parent = parent->d_ptr->parent) && (!hidden || !parent->d_func()->visible));
+}
+
+/*!
+    \internal
+*/
+void QGraphicsItemPrivate::clearSubFocus()
+{
+    // Reset focus child chain.
+    QGraphicsItem *parent = q_ptr;
+    do {
+        if (parent->d_ptr->subFocusItem != q_ptr)
+            break;
+        parent->d_ptr->subFocusItem = 0;
+    } while (!parent->isWindow() && (parent = parent->d_ptr->parent));
+}
+
+/*!
+    \internal
 
     Tells us if it is a proxy widget
 */
@@ -10164,6 +10233,9 @@ QDebug operator<<(QDebug debug, QGraphicsItem::GraphicsItemFlag flag)
     case QGraphicsItem::ItemAcceptsInputMethod:
         str = "ItemAcceptsInputMethod";
         break;
+    case QGraphicsItem::ItemAutoDetectsFocusProxy:
+        str = "ItemAutoDetectsFocusProxy";
+        break;
     }
     debug << str;
     return debug;