bevy_mod_observable_timer

This crate provides an observer-based timer system for bevy entities. Any entity may have an [ObservableTimer] component attached to it, which will produce observable lifetime cycle triggers.

• [TimerStarted] is triggered immediately after inserting a new ObservableTimer (including when overwriting an old one).
• [TimerFinished] is triggered after each elapsed interval.
• [TimerStopped] is triggered when the ObservableTimer component is removed/despawned.

When a timer finishes it will automatically perform some behavior. By default this is despawning its attached entity. See [TimerFinishBehavior] for more information.

Basic Example

use bevy::{log::LogPlugin, prelude::*};
use bevy_mod_observable_timer::*;

fn main() {
    App::new()
        .add_plugins((
            MinimalPlugins,
            LogPlugin::default(),
            ObservableTimerPlugin::default(),
        ))
        .add_systems(Startup, startup)
        .run();
}

fn startup(mut commands: Commands) {
    commands
        .spawn(ObservableTimer::from_seconds(1.0, TimerMode::Repeating))
        .observe(|_: Trigger<TimerStarted>| {
            info!("Timer started");
        })
        .observe(
            |trigger: Trigger<TimerFinished>, mut count: Local<usize>, mut commands: Commands| {
                *count += 1;
                info!("Timer finished (#{})", *count);

                if *count == 5 {
                    commands.entity(trigger.target()).despawn();
                }
            },
        )
        .observe(
            |_: Trigger<TimerStopped>, mut app_exit: EventWriter<AppExit>| {
                info!("Timer stopped");
                app_exit.write_default();
            },
        );
}

Output:

Timer started
Timer finished (#1)
Timer finished (#2)
Timer finished (#3)
Timer finished (#4)
Timer finished (#5)
Timer stopped

Compatibility

License

Except where noted, all code in this repository is dual-licensed under either:

• MIT License (LICENSE-MIT or http://opensource.org/licenses/MIT)
• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)

at your option.