The ::drag-begin signal is emitted on the drag source when a drag is started. A typical reason to connect to this signal is to set up a custom drag icon with e.g. gtk_drag_source_set_icon_pixbuf().

Note that some widgets set up a drag icon in the default handler of this signal, so you may have to use g_signal_connect_after() to override what the default handler did.

class Widget
void delegate dlg
ConnectFlags connectFlags = cast(ConnectFlags)0