godot/demos/gui/drag_and_drop/drag_drop_script.gd

extends ColorPickerButton


#virtual function
func get_drag_data(pos):
	
	#use another colorpicker as drag preview
	var cpb = ColorPickerButton.new()
	cpb.set_color( get_color() )
	cpb.set_size(Vector2(50,50))
	set_drag_preview(cpb)
	#return color as drag data
	return get_color()

#virtual function	
func can_drop_data(pos, data):
	return typeof(data)==TYPE_COLOR

#virtual function
func drop_data(pos, data):
	set_color(data)