Struct bevy_ui_navigation::NavMenu

pub struct NavMenu { /* private fields */ }

A menu that isolate children Focusables from other focusables and specify navigation method within itself.

A NavMenu can be used to:

• Prevent navigation from one specific submenu to another
• Specify the cycle directions of navigation (going left when focusing on a leftmost Focusable may go to the rightmost Focusable)
• Specify “scope menus” such that a NavRequest::ScopeMove emitted when the focused element is a Focusable nested within this NavMenu will navigate this menu.
• Specify submenus and specify from where those submenus are reachable

Important

There are two important invariants to keep in mind:

1. There should be no cycles in the navigation graph, ie: You must ensure this doesn’t create a cycle. You shouldn’t be able to reach NavMenu X from Focusable Y if there is a path from NavMenu X to Focusable Y.
2. There must be at least one child Focusable in the ui graph for each NavMenu when sending a NavRequest

Implementations

impl NavMenu

pub fn new(focus_parent: Option<Entity>) -> Self

Prefer NavMenu::reachable_from and NavMenu::root to this

new is useful to programmatically set the parent if you have an optional value. This saves you from a match focus_parent.

pub fn root() -> Self

Set this menu as having no parents

pub fn closed(self) -> Self

Set this menu as closed (no cycling)

pub fn cycling(self) -> Self

Set this menu as cycling

ie: going left from the leftmost element goes to the rightmost element

pub fn scope(self) -> Self

Set this menu as a scope menu

Meaning: controlled with NavRequest::ScopeMove even when the focused element is not in this menu, but in a submenu reachable from this one.

pub fn reachable_from(focusable: Entity) -> Self

Set this menu as reachable from a given Focusable

When requesting NavRequest::Action when focusable is focused, the focus will be changed to a focusable within this menu.

Important

You must ensure this doesn’t create a cycle. Eg: you shouldn’t be able to reach NavMenu X from Focusable Y if there is a path from NavMenu X to Focusable Y.

Trait Implementations

impl Clone for NavMenu

fn clone(&self) -> NavMenu

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Component for NavMenu where
    Self: Send + Sync + 'static, 

type Storage = TableStorage

impl Debug for NavMenu

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.