some improvement for Overlays being the child of the grabbed item - not

finaly solved

playground/parrots/BlurredOverlay.cpp

@@ -13,9 +13,28 @@
 
 #include <qpointer.h>
 
-class BlurredOverlayPrivate : public QQuickItemPrivate, public QQuickItemChangeListener
+namespace
+{
+    class TransformNode final : public QSGTransformNode
     {
       public:
+        bool isSubtreeBlocked() const override
+        {
+            return isBlocked || QSGTransformNode::isSubtreeBlocked();
+        }
+
+        bool isBlocked = false;;
+    };
+}
+
+class BlurredOverlayPrivate final : public QQuickItemPrivate, public QQuickItemChangeListener
+{
+  public:
+
+    QSGTransformNode* createTransformNode() override
+    {
+        return new TransformNode();
+    }
 
     void itemGeometryChanged( QQuickItem*,
         QQuickGeometryChange change, const QRectF& )
@@ -214,7 +233,22 @@ QSGNode* BlurredOverlay::updatePaintNode( QSGNode* oldNode, UpdatePaintNodeData*
 
     d->updateTexture( layer );
 
+    {
+        auto itemNode = static_cast< TransformNode* >( d->itemNode() );
+
+        /*
+            When we are a child of grabbedItem we end up in a recursion
+            that fails when initializing the texture twice. No problem
+            as we explicitly do not want to become part of it.
+
+            Disabling our subtree avoids the problem with the initialization
+            - the texture contains some artifacts from our own children. TODO ...
+         */
+        itemNode->isBlocked = true;
         layer->updateTexture();
+        itemNode->isBlocked = false;
+    }
+
     node->setRect( QRectF( 0, 0, width(), height() ) );
 
     return node;

playground/parrots/main.cpp

@@ -26,11 +26,20 @@ class ButtonBox : public QskLinearBox
 {
   public:
     ButtonBox( QQuickItem* parent = nullptr )
-        : QskLinearBox( parent )
+        : QskLinearBox( Qt::Vertical, parent )
     {
-        ( void ) new QskPushButton( "Button 1", this );
-        ( void ) new QskPushButton( "Button 2", this );
-        ( void ) new QskPushButton( "Button 3", this );
+        setMargins( 20 );
+
+        auto label = new QskGraphicLabel( this );
+
+        const QImage image( ":/images/parrots.jpg" );
+        label->setGraphic( QskGraphic::fromImage( image ) );
+        label->setSizePolicy( QskSizePolicy::Fixed, QskSizePolicy::Fixed );
+        label->setLayoutAlignmentHint( Qt::AlignCenter );
+
+
+        auto button = new QskPushButton( "Button", this );
+        button->setLayoutAlignmentHint( Qt::AlignHCenter | Qt::AlignBottom );
     }
 };
 
@@ -138,7 +147,12 @@ class MainView : public QskControl
 
         m_background = new BackgroundItem( this );
 
+#if 1
         m_blurredBox = new BlurredBox( this );
+#else
+        // unsatisfying: see comment in BlurredOverlay::updatePaintNode TODO ...
+        m_blurredBox = new BlurredBox( m_background );
+#endif
         m_blurredBox->setGrabbedItem( m_background );
 
         (void )new ButtonBox( m_blurredBox );