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When a drop destination has accepted a dragged item, certain signals will be emitted, depending on what action has been selected. For instance, the user might have held down the Shift key to specify a move rather than a copy. Remember that the user can only select the actions which you have specified in your calls to drag_dest_set() and drag_source_set().
18.3.1. Copy
The source widget will emit these signals, in this order:
- drag_begin: Provides DragContext.
- drag_data_get: Provides info about the dragged data format, and a Gtk::SelectionData structure, in which you should put the requested data.
- drag_end: Provides DragContext.
The destination widget will emit these signals, in this order:
- drag_motion: Provides DragContext and coordinates. You can call the drag_status() method of the DragContext to indicate which action will be accepted.
- drag_drop: Provides DragContext and coordinates. You can call drag_get_data(), which triggers the drag_data_get signal in the source widget, and then the drag_data_received signal in the destination widget.
- drag_data_received: Provides info about the dragged data format, and a Gtk::SelectionData structure which contains the dropped data. You should call the drag_finish() method of the DragContext to indicate whether the operation was successful.