Don't polish QDeclarativeItems.

Avoids unnecessary processing and assumptions we would not want to
preserve in the future.

Task-number: QTBUG-10217
Reviewed-by: Martin Jones

2 files changed, 16 insertions, 6 deletions

diff --git a/src/declarative/graphicsitems/qdeclarativeitem.cpp b/src/declarative/graphicsitems/qdeclarativeitem.cpp
index 9547884..2841ac3 100644
--- a/src/declarative/graphicsitems/qdeclarativeitem.cpp
+++ b/src/declarative/graphicsitems/qdeclarativeitem.cpp
@@ -2681,7 +2681,13 @@ bool QDeclarativeItem::sceneEvent(QEvent *event)
     }
 }
 
-/*! \internal */
+/*!
+    \reimp
+
+    Note that unlike QGraphicsItems, QDeclarativeItem::itemChange() is \e not called
+    during initial widget polishing. Items wishing to optimize start-up construction
+    should instead consider using componentComplete().
+*/
 QVariant QDeclarativeItem::itemChange(GraphicsItemChange change,
                                        const QVariant &value)
 {
diff --git a/src/gui/graphicsview/qgraphicsscene.cpp b/src/gui/graphicsview/qgraphicsscene.cpp
index 344df30..ae0abf9 100644
--- a/src/gui/graphicsview/qgraphicsscene.cpp
+++ b/src/gui/graphicsview/qgraphicsscene.cpp
@@ -2545,12 +2545,16 @@ void QGraphicsScene::addItem(QGraphicsItem *item)
         return;
     }
 
-    if (d->unpolishedItems.isEmpty()) {
-        QMetaMethod method = metaObject()->method(d->polishItemsIndex);
-        method.invoke(this, Qt::QueuedConnection);
+    // QDeclarativeItems do not rely on initial itemChanged message, as the componentComplete
+    // function allows far more opportunity for delayed-construction optimization.
+    if (!item->d_ptr->isDeclarativeItem) {
+        if (d->unpolishedItems.isEmpty()) {
+            QMetaMethod method = metaObject()->method(d->polishItemsIndex);
+            method.invoke(this, Qt::QueuedConnection);
+        }
+        d->unpolishedItems.append(item);
+        item->d_ptr->pendingPolish = true;
     }
-    d->unpolishedItems.append(item);
-    item->d_ptr->pendingPolish = true;
 
     // Detach this item from its parent if the parent's scene is different
     // from this scene.