Struct On

pub struct On<E>
where
    E: EntityEvent,
{ /* private fields */ }

An event listener with a callback that is triggered when an EntityEvent bubbles past or targets this entity.

The building block for all event listeners is the On::run method. All the other provided methods are convenience methods that describe the most common functionality. However, because these all use the public On::run method internally, you can easily define your own variants that have the behavior you want!

Implementations

impl<E> On<E>

where E: EntityEvent,

pub fn run<Marker>(callback: impl IntoSystem<(), (), Marker>) -> On<E>

Run a callback system every time this event listener is triggered. This can be a closure or a function, as described by bevy’s documentation. The only notable difference from Bevy systems is that the callback system can access a resource with event data, ListenerInput. You can more easily access this with the system params Listener and ListenerMut.

pub fn add_command<C>() -> On<E>

where C: From<ListenerInput<E>> + Command + Send + Sync + 'static,

Add a single Command any time this event listener is triggered. The command must implement From<E>.

pub fn commands_mut( func: impl Send + Sync + FnMut(&mut ListenerInput<E>, &mut Commands<'_, '_>) + 'static, ) -> On<E>

Get mutable access to Commands any time this event listener is triggered.

pub fn target_commands_mut( func: impl Send + Sync + FnMut(&mut ListenerInput<E>, &mut EntityCommands<'_>) + 'static, ) -> On<E>

Get mutable access to the target entity’s EntityCommands using a closure any time this event listener is triggered.

pub fn target_insert(bundle: impl Bundle + Clone) -> On<E>

Insert a bundle on the target entity any time this event listener is triggered.

pub fn target_remove<B>() -> On<E>

where B: Bundle,

Remove a bundle from the target entity any time this event listener is triggered.

pub fn target_component_mut<C>( func: impl Send + Sync + FnMut(&mut ListenerInput<E>, &mut C) + 'static, ) -> On<E>

where C: Component,

Get mutable access to a specific component on the target entity using a closure any time this event listener is triggered. If the component does not exist, an error will be logged.

pub fn listener_commands_mut( func: impl Send + Sync + FnMut(&mut ListenerInput<E>, &mut EntityCommands<'_>) + 'static, ) -> On<E>

Get mutable access to the listener entity’s EntityCommands using a closure any time this event listener is triggered.

pub fn listener_insert(bundle: impl Bundle + Clone) -> On<E>

Insert a bundle on the listener entity any time this event listener is triggered.

pub fn listener_remove<B>() -> On<E>

where B: Bundle,

Remove a bundle from the listener entity any time this event listener is triggered.

pub fn listener_component_mut<C>( func: impl Send + Sync + FnMut(&mut ListenerInput<E>, &mut C) + 'static, ) -> On<E>

where C: Component,

Get mutable access to a specific component on the listener entity using a closure any time this event listener is triggered. If the component does not exist, an error will be logged.

pub fn send_event<F>() -> On<E>

where F: Event + From<ListenerInput<E>>,

Send an event F any time this event listener is triggered.

Trait Implementations

impl<E> Component for On<E>

where E: EntityEvent, On<E>: Send + Sync + 'static,

const STORAGE_TYPE: StorageType = bevy_ecs::component::StorageType::Table

A constant indicating the storage type used for this component.

fn register_component_hooks(_hooks: &mut ComponentHooks)

Called when registering this component, allowing mutable access to its ComponentHooks.

impl<E> Default for On<E>

where E: Default + EntityEvent,

fn default() -> On<E>

Returns the “default value” for a type.