pub trait ActionBarExt: IsA<ActionBar> + Sealed + 'static {
// Provided methods
fn center_widget(&self) -> Option<Widget> { ... }
fn pack_end(&self, child: &impl IsA<Widget>) { ... }
fn pack_start(&self, child: &impl IsA<Widget>) { ... }
fn set_center_widget(&self, center_widget: Option<&impl IsA<Widget>>) { ... }
fn child_pack_type<T: IsA<Widget>>(&self, item: &T) -> PackType { ... }
fn set_child_pack_type<T: IsA<Widget>>(&self, item: &T, pack_type: PackType) { ... }
fn child_position<T: IsA<Widget>>(&self, item: &T) -> i32 { ... }
fn set_child_position<T: IsA<Widget>>(&self, item: &T, position: i32) { ... }
}