Struct MenuItems 

pub struct MenuItems(/* private fields */);

The set of menu items a board enables.

MenuItem::Status and every Back entry are always present regardless of how the set was built.

Implementations

impl MenuItems

pub const fn new() -> Self

Just the entries no board can do without.

pub const fn all() -> Self

Every item this crate defines.

pub const fn with(self, item: MenuItem) -> Self

Enable one more item.

pub const fn without(self, item: MenuItem) -> Self

Disable one item.

The counterpart to with for boards that start from all and name what they cannot do, which is the shorter list on most hardware. Removing every entry of a level removes the way into it too — see level_is_empty — so a board need not also remember to disable the submenu that led there.

pub const fn contains(self, item: MenuItem) -> bool

pub const fn len(self) -> u32

Number of enabled items across the whole tree. Always at least one.

pub const fn is_empty(self) -> bool

pub fn level_is_empty(self, level: Level) -> bool

Whether a level has anything worth entering: any enabled entry that is not its own Back.

A submenu whose entries are all disabled is not shown at all, rather than opening onto a list containing only Back.

pub fn entries(self, level: Level) -> impl Iterator<Item = MenuItem>

The enabled entries of one level, in navigation order.

This is what a renderer draws a list from, so it and step must agree about what is on screen.

pub fn first_after_back(self, level: Level) -> MenuItem

The entry a freshly entered level should highlight: the first one after Back.

Highlighting the exit of a screen the user just asked to enter would waste the press that got them there. A level with nothing but Back falls back to it, though level_is_empty means such a level is never entered.

Trait Implementations

impl Clone for MenuItems

fn clone(&self) -> MenuItems

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MenuItems

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

Formats the value using the given formatter.

impl Default for MenuItems

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for MenuItems

fn eq(&self, other: &MenuItems) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for MenuItems

impl Eq for MenuItems

impl StructuralPartialEq for MenuItems