Struct EventReader 

pub struct EventReader<'a, T: 'static> { /* private fields */ }

Reads unread Events<T> as a system parameter. Each reader keeps its own cursor (like Local), so multiple readers of the same event type don’t interfere with each other.

Implementations

impl<'a, T: 'static> EventReader<'a, T>

pub fn iter(&mut self) -> impl Iterator<Item = &T> + '_

Every event sent since this reader last called iter, oldest first.

pub fn is_empty(&self) -> bool

true if there’s nothing unread for this reader.

Trait Implementations

impl<T: 'static> SystemParam for EventReader<'static, T>

type Item<'a> = EventReader<'a, T>

The value actually handed to the system function.

type State = usize

Per-system persistent state (e.g. Local’s stored value) — () for anything stateless.

fn fetch<'a>( _world: &'a World, resources: &'a Resources, state: &'a mut Self::State, ) -> Self::Item<'a>