See Also: Action Members
As well as the callback that is called when the action gets activated, the following also gets associated with the action:
The action will also have some state information:
Apart from regular actions, there are toggle actions, which can be toggled between two states and radio actions, of which only one in a group can be in the "active" state. Other actions can be implemented as Gtk.Action subclasses.
Each action can have one or more proxy menu item, toolbar button or other proxy widgets. Proxies mirror the state of the action (text label, tooltip, icon, visible, sensitive, etc), and should change when the action's state changes. When the proxy is activated, it should activate its action.