Trait DelayedCommandsExt 

pub trait DelayedCommandsExt<'w> {
    // Required method
    fn delayed(&mut self) -> DelayedCommands<'w, '_>;
}

Extension trait for Commands that provides delayed command functionality.

Required Methods

fn delayed(&mut self) -> DelayedCommands<'w, '_>

Returns a DelayedCommands instance that can be used to queue commands to be submitted at a later point in time.

When dropped, the DelayedCommands submits spawn commands that will spawn DelayedCommandQueue entities. The entities are checked by the check_delayed_command_queues system, and their queues are submitted when the specified time has elapsed.

Usage

fn my_system(mut commands: Commands) {
    // Spawn an entity after one second
    commands.delayed().secs(1.0).spawn_empty();
}

Entity allocation happens immediately even if the spawn command is delayed. This allows you to queue delayed commands on an entity that hasn’t been spawned yet.

fn my_system(mut commands: Commands) {
    let mut delayed = commands.delayed();
    // spawn an entity after 1 second, then despawn it a second later
    let entity = delayed.secs(1.0).spawn_empty().id();
    delayed.secs(2.0).entity(entity).despawn();
}

Timing

Delayed commands are currently checked against the default clock in the PreUpdate schedule. There’s currently no way to specify different clocks for different delayed commands - this is a limitation of the system and if you need this behavior you’ll likely have to implement your own delay system.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl<'w, 's> DelayedCommandsExt<'w> for Commands<'w, 's>

fn delayed(&mut self) -> DelayedCommands<'w, '_>

Implementors