Qt Code:
  1. QTreeWidget* tree = new QTreeWidget( this );
  2. tree->setDragEnabled( true );
  3. tree->setAcceptDrops( true );
  4. tree->setDropIndicatorShown( true );
  5. tree->setDefaultDropAction( Qt::MoveAction ); // that's what you need
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This should do it. No need to set setDragDropMode() as setDragEnabled() and setAcceptDrops() do it for you.