QGraphicsSceneDragDropEvent has modifiers only when they have been released

To reproduce:

In KDE dolphin filemanager :

1. Drag a file
2. Drop it in another directory while pressing CTRL

Actual

• A dialog appears letting you choose whether to move or copy the file

Expected

• The file is copied at drop destination

The issue is that QGraphicsSceneDragDropEvent carries modifiers information only once the modifier has been released or when continously pressed.

This illustrates in two other wrong behaviors.

In KDE dolphin filemanager :

1. Drag a file
2. Press and release Ctrl modifier
3. Drop it in another directory

Actual

• The file is copied at drop destination
• In DolphinView::slotItemDropEvent QGraphicsSceneDragDropEvent event was:
• QGraphicsSceneDragDropEvent(proposedAction=CopyAction, possibleActions=CopyAction|MoveAction|LinkAction, source=DolphinMainWindow(0x556d7a24a5b0, name="Dolphin#1"), buttons=LeftButton, ControlModifier, pos=109,510, scenePos=109,510, screenPos=354,584

Expected

• A dialog appears letting you choose whether to move or copy the file

In KDE dolphin filemanager :

1. Drag a file while pressing Ctrl modifier
2. Release the Ctrl modifier
3. Drop it in another directory

Actual

• The file is copied at drop destination
• In DolphinView::slotItemDropEvent QGraphicsSceneDragDropEvent event was:
• QGraphicsSceneDragDropEvent(proposedAction=CopyAction, possibleActions=CopyAction|MoveAction|LinkAction, source=DolphinMainWindow(0x556d7a24a5b0, name="Dolphin#1"), buttons=LeftButton, ControlModifier, pos=157,524, scenePos=157,524, screenPos=402,598

Expected

• A dialog appears letting you choose whether to move or copy the file