Function parts 

pub fn parts() -> &'static [fn() -> Description]

The components that stand only in a slot of another, which reads their props: a property list’s facts, a navigation list’s places and sections, a menu’s commands, separators and emoji bar, a row’s swipe, the items of a virtual list, and what a view attaches to the element it stands in (its context menu, hover toolbar and swipe). Generated: every #[derive(Component)] props that no described widget is built from.