42e6dc8987
# Objective - The current `EventReader::iter` has been determined to cause confusion among new Bevy users. It was suggested by @JoJoJet to rename the method to better clarify its usage. - Solves #9624 ## Solution - Rename `EventReader::iter` to `EventReader::read`. - Rename `EventReader::iter_with_id` to `EventReader::read_with_id`. - Rename `ManualEventReader::iter` to `ManualEventReader::read`. - Rename `ManualEventReader::iter_with_id` to `ManualEventReader::read_with_id`. --- ## Changelog - `EventReader::iter` has been renamed to `EventReader::read`. - `EventReader::iter_with_id` has been renamed to `EventReader::read_with_id`. - `ManualEventReader::iter` has been renamed to `ManualEventReader::read`. - `ManualEventReader::iter_with_id` has been renamed to `ManualEventReader::read_with_id`. - Deprecated `EventReader::iter` - Deprecated `EventReader::iter_with_id` - Deprecated `ManualEventReader::iter` - Deprecated `ManualEventReader::iter_with_id` ## Migration Guide - Existing usages of `EventReader::iter` and `EventReader::iter_with_id` will have to be changed to `EventReader::read` and `EventReader::read_with_id` respectively. - Existing usages of `ManualEventReader::iter` and `ManualEventReader::iter_with_id` will have to be changed to `ManualEventReader::read` and `ManualEventReader::read_with_id` respectively.
62 lines
2.0 KiB
Rust
62 lines
2.0 KiB
Rust
use bevy_ecs::prelude::*;
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// In this example a system sends a custom event with a 50/50 chance during any frame.
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// If an event was send, it will be printed by the console in a receiving system.
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fn main() {
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// Create a new empty world and add the event as a resource
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let mut world = World::new();
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world.insert_resource(Events::<MyEvent>::default());
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// Create a schedule to store our systems
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let mut schedule = Schedule::default();
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// Events need to be updated in every frame in order to clear our buffers.
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// This update should happen before we use the events.
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// Here, we use system sets to control the ordering.
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#[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
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pub struct FlushEvents;
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schedule.add_systems(Events::<MyEvent>::update_system.in_set(FlushEvents));
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// Add systems sending and receiving events after the events are flushed.
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schedule.add_systems((
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sending_system.after(FlushEvents),
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receiving_system.after(sending_system),
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));
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// Simulate 10 frames of our world
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for iteration in 1..=10 {
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println!("Simulating frame {iteration}/10");
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schedule.run(&mut world);
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}
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}
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// This is our event that we will send and receive in systems
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#[derive(Event)]
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struct MyEvent {
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pub message: String,
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pub random_value: f32,
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}
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// In every frame we will send an event with a 50/50 chance
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fn sending_system(mut event_writer: EventWriter<MyEvent>) {
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let random_value: f32 = rand::random();
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if random_value > 0.5 {
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event_writer.send(MyEvent {
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message: "A random event with value > 0.5".to_string(),
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random_value,
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});
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}
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}
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// This system listens for events of the type MyEvent
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// If an event is received it will be printed to the console
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fn receiving_system(mut event_reader: EventReader<MyEvent>) {
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for my_event in event_reader.read() {
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println!(
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" Received message {:?}, with random value of {}",
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my_event.message, my_event.random_value
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);
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}
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}
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