1 files changed, 67 insertions, 0 deletions

diff --git a/src/quick/items/qquickitem.cpp b/src/quick/items/qquickitem.cpp
index 51bec66d22..54c63c4cbf 100644
--- a/src/quick/items/qquickitem.cpp
+++ b/src/quick/items/qquickitem.cpp
@@ -2622,6 +2622,11 @@ void QQuickItemPrivate::refWindow(QQuickWindow *c)
     Q_ASSERT(window == 0);
     window = c;
 
+    if (q->flags() & QQuickItem::ItemHasContents) {
+        QObject::connect(window, SIGNAL(sceneGraphInvalidated()), q, SIGNAL(sceneGraphInvalidated()), Qt::DirectConnection);
+        QObject::connect(window, SIGNAL(sceneGraphInitialized()), q, SIGNAL(sceneGraphInitialized()), Qt::DirectConnection);
+    }
+
     if (polishScheduled)
         QQuickWindowPrivate::get(window)->itemsToPolish.insert(q);
 
@@ -2651,6 +2656,11 @@ void QQuickItemPrivate::derefWindow()
     if (--windowRefCount > 0)
         return; // There are still other references, so don't set window to null yet.
 
+    if (q->flags() & QQuickItem::ItemHasContents) {
+        QObject::disconnect(window, SIGNAL(sceneGraphInvalidated()), q, SIGNAL(sceneGraphInvalidated()));
+        QObject::disconnect(window, SIGNAL(sceneGraphInitialized()), q, SIGNAL(sceneGraphInitialized()));
+    }
+
     q->releaseResources();
     removeFromDirtyList();
     QQuickWindowPrivate *c = QQuickWindowPrivate::get(window);
@@ -5794,10 +5804,67 @@ void QQuickItem::setFlags(Flags flags)
     if (int(flags & ItemClipsChildrenToShape) != int(d->flags & ItemClipsChildrenToShape))
         d->dirty(QQuickItemPrivate::Clip);
 
+    if (window() && (flags & ItemHasContents) ^ (d->flags & ItemHasContents)) {
+        if (flags & ItemHasContents)  {
+            connect(window(), SIGNAL(sceneGraphInvalidated()), this, SIGNAL(sceneGraphInvalidated()), Qt::DirectConnection);
+            connect(window(), SIGNAL(sceneGraphInitialized()), this, SIGNAL(sceneGraphInitialized()), Qt::DirectConnection);
+        } else {
+            disconnect(window(), SIGNAL(sceneGraphInvalidated()), this, SIGNAL(sceneGraphInvalidated()));
+            disconnect(window(), SIGNAL(sceneGraphInitialized()), this, SIGNAL(sceneGraphInitialized()));
+        }
+    }
+
     d->flags = flags;
 }
 
 /*!
+    \fn void QQuickItem::sceneGraphInvalidated()
+
+    This signal is emitted when the scene graph is invalidated for
+    items that have the ItemHasContents flag set.
+
+    QSGNode instances will be cleaned up by the scene graph
+    automatically. An application will only need to react to this signal
+    to clean up resources that are stored and managed outside the
+    QSGNode structure returned from updatePaintNode().
+
+    When the scene graph is using a dedicated render thread, this
+    signal will be emitted on the scene graph's render thread. The
+    GUI thread is blocked for the duration of this call. Connections
+    should for this reason be made using Qt::DirectConnection.
+
+    The OpenGL context of this item's window will be bound when this
+    signal is emitted. The only exception is if the native OpenGL has
+    been destroyed outside Qt's control, for instance through
+    EGL_CONTEXT_LOST.
+
+    \since 5.4
+    \since QtQuick 2.4
+
+    \sa QQuickWindow::sceneGraphInvalidated()
+ */
+
+/*!
+    \fn void QQuickItem::sceneGraphInitialized()
+
+    This signal is emitted when the scene graph is is initialized for
+    items that have the ItemHasContents flag set.
+
+    When the scene graph is using a dedicated render thread, this
+    function will be called on the scene graph's render thread. The
+    GUI thread is blocked for the duration of this call. Connections
+    should for this reason be made using Qt::DirectConnection.
+
+    The OpenGL context of this item's window will be bound when
+    this signal is emitted.
+
+    \since 5.4
+    \since QtQuick 2.4
+
+    \sa QQuickWindow::sceneGraphInitialized()
+ */
+
+/*!
   \qmlproperty real QtQuick::Item::x
   \qmlproperty real QtQuick::Item::y
   \qmlproperty real QtQuick::Item::width