Gio.ActionGroup::get_action_parameter_type

function vfunc_get_action_parameter_type(action_name: String): GLib.VariantType {
}
  

Queries the type of the parameter that must be given when activating the named action within action_group.

When activating the action using Gio.ActionGroup.prototype.activate_action, the GLib.Variant given to that function must be of the type returned by this function.

In the case that this function returns null, you must not give any GLib.Variant, but null instead.

The parameter type of a particular action will never change but it is possible for an action to be removed and for a new action to be added with the same name but a different parameter type.

Since 2.28