Observe this simple scene example which puts two buttons on the scene:


Qt Code: 
  1. auto ww = new QGraphicsProxyWidget();
  2. 	ww->setWidget(new QPushButton());
  3. 	ww->setPos(900, 900);
  4.  
  5. 	auto ww2 = new QGraphicsProxyWidget();
  6. 	ww2->setWidget(new QPushButton());
  7. 	ww2->setPos(500, 500);
  8.  
  9. 	auto scene = new QGraphicsScene();
  10. 	scene->addItem(ww);
  11. 	scene->addItem(ww2);
  12.  
  13. 	auto view = new QGraphicsView();
  14. 	view->resize(1000, 1000);
  15. 	view->setScene(scene);
  16. 	view->show();
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Everything works fine, and the two buttons appear at the specified positions.

However, if we now add the itemismovable flag to them like so:


Qt Code: 
  1. auto ww = new QGraphicsProxyWidget();
  2. 	ww->setFlags(QGraphicsItem::ItemIsMovable | QGraphicsItem::ItemIsSelectable);
  3. 	ww->setWidget(new QPushButton());
  4. 	ww->setPos(900, 900);
  5.  
  6. 	auto ww2 = new QGraphicsProxyWidget();
  7. 	ww2->setFlags(QGraphicsItem::ItemIsMovable | QGraphicsItem::ItemIsSelectable);
  8. 	ww2->setWidget(new QPushButton());
  9. 	ww2->setPos(500, 500);
  10.  
  11. ...
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the the initial position of the items breaks. They both put over each other at position (0,0). However, if I call ww->setPos(...) after the view is shown, then that works.


Any idea what might be causing this?






Environment:

Qt 5.7
VS2013U5
Windows7SP1