#GooCanvasItemIFace holds the virtual methods that make up the
#GooCanvasItem interface.
Simple canvas items only need to implement the get_parent(), set_parent(),
get_bounds(), get_items_at(), update() and paint() methods (and also
get_requested_area() and allocate_area() if they are going to be used
inside a layout container like #GooCanvasTable).
Items that support transforms should also implement get_transform() and
set_transform(). Items that support styles should implement get_style()
and set_style().
Container items must implement get_canvas(), set_canvas(),
get_n_children(), get_child() and request_update(). Containers that support
dynamic changes to their children should implement add_child(),
move_child() and remove_child(). Layout containers like #GooCanvasTable
may implement get_child_property(), set_child_property() and
get_transform_for_child().
#GooCanvasItemIFace holds the virtual methods that make up the #GooCanvasItem interface.
Simple canvas items only need to implement the get_parent(), set_parent(), get_bounds(), get_items_at(), update() and paint() methods (and also get_requested_area() and allocate_area() if they are going to be used inside a layout container like #GooCanvasTable).
Items that support transforms should also implement get_transform() and set_transform(). Items that support styles should implement get_style() and set_style().
Container items must implement get_canvas(), set_canvas(), get_n_children(), get_child() and request_update(). Containers that support dynamic changes to their children should implement add_child(), move_child() and remove_child(). Layout containers like #GooCanvasTable may implement get_child_property(), set_child_property() and get_transform_for_child().