1. GraphicsPolygonItem subclass of QGraphicsPolygonItem; GraphicsView subclass of QGraphicsView;

2. There are two GraphicsPolygonItem items(we call them item-A item-B) in the scene(GraphicsView hold the scene);

3. I can doubleclick to select one item(item-A), but when I doubleclick the other(item-B), it doing nothing. But, I doubleclick item-B once again, item-B will be selected. It means I have to doubleclick twice to switch and select the other. Yes, it is switch and select, because if i only click item-A, it don't need doubleclick twice.

4. I have debug it as, when I doubleclick the other item, it will not come into the GraphicsPolygonItem::mouseDoubleClickEvent(QGraphi csSceneMouseEvent *event).

here is the code: //GraphicsPolygonItem

Qt Code:
  1. void GraphicsPolygonItem::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)
  2. {
  3. /*here doing some thing for select item......*/
  4. //...
  5. this->QGraphicsPolygonItem::update();
  6. QGraphicsPolygonItem::mouseDoubleClickEvent(event);
  7. }
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Qt Code:
  1. void GraphicView::mouseDoubleClickEvent(QMouseEvent *event)
  2. {
  3. QGraphicsView::mouseDoubleClickEvent(event);
  4. }
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Be expecting your response! Thanks!