gtk-actionable-action-target (object)

object -- a gtk-actionable widget
value -- a g-variant parameter as the target value, or null-pointer

Accessor of the action-target slot of the gtk-actionable inferface.

The gtk-actionable-action-target slot access function gets the current target value of an actionable widget. The (setf gtk-actionable-action-target) slot access function sets the target value.

If the value argument is a null-pointer then the target value is unset.

The target value has two purposes. First, it is used as the parameter to activation of the action associated with the gtk-actionable widget. Second, it is used to determine if the widget should be rendered as "active" - the widget is active if the state is equal to the given target.

Consider the example of associating a set of buttons with a g-action object with string state in a typical radio button situation. Each button will be associated with the same action, but with a different target value for that action. Clicking on a particular button will activate the action with the target of that button, which will typically cause the state of the action to change to that value. Since the state of the action is now equal to the target value of the button, the button will now be rendered as active and the other buttons, with different targets, rendered inactive.

(let ((button (make-instance 'gtk-button)))
  (setf (gtk-actionable-action-target button) (g-variant-new-int16 128))
  (g-variant-int16 (gtk-actionable-action-target button)))
=> 128    

The C implementation knows in addition the gtk_application_get_action_target_value () and gtk_application_set_action_target_value () functions. In the Lisp implementation these functions are replaced by the gtk-application-action-target slot access function.