Remove the callback facility from context node.

- It's not really necessary.
- It's probably a mis-use of QSGNode::preprocess()
  - Because it triggers a race between object deletion in the main thread
  and preprocess() in the render thread.

Change-Id: I51433f508db306aab53398f8c3d1d8c9d9e986fd
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>
Reviewed-by: Yunqiao Yin <charles.yin@nokia.com>

1 files changed, 3 insertions, 12 deletions

diff --git a/src/quick/items/context2d/qquickcanvasitem.cpp b/src/quick/items/context2d/qquickcanvasitem.cpp
index 783fedf9fc..7031294ecc 100644
--- a/src/quick/items/context2d/qquickcanvasitem.cpp
+++ b/src/quick/items/context2d/qquickcanvasitem.cpp
@@ -96,16 +96,6 @@ QQuickCanvasItemPrivate::~QQuickCanvasItemPrivate()
     qDeleteAll(images);
 }
 
-class QQuickCanvasItemCallback : public QQuickCanvasItemNode::Callback
-{
-public:
-    QQuickCanvasItemCallback(QQuickCanvasItemPrivate *d):item(d) {}
-    void process() const {
-        // on SG render thread
-        item->context->sync();
-    }
-    QQuickCanvasItemPrivate *item;
-};
 
 /*!
     \qmlclass Canvas QQuickCanvasItem
@@ -573,10 +563,11 @@ QSGNode *QQuickCanvasItem::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData
     QQuickCanvasItemNode *node = static_cast<QQuickCanvasItemNode*>(oldNode);
     if (!node) {
         node = new QQuickCanvasItemNode;
-        if (d->renderStrategy == QQuickCanvasItem::Cooperative)
-            node->setCallback(new QQuickCanvasItemCallback(d));
     }
 
+    if (d->renderStrategy == QQuickCanvasItem::Cooperative)
+        d->context->sync();
+
     node->setTexture(d->context->texture());
     node->setSize(d->canvasWindow.size());
     node->update();