Struct Event

pub struct Event { /* private fields */ }

A wrapper around a message, providing metadata on how the event travels through the view tree.

Implementations

impl Event

pub fn new<M>(message: M) -> Event

where M: Any + Send,

Creates a new event with a specified message.

pub fn target(self, entity: Entity) -> Event

Sets the target of the event.

pub fn origin(self, entity: Entity) -> Event

Sets the origin of the event.

pub fn propagate(self, propagation: Propagation) -> Event

Sets the propagation of the event.

pub fn direct(self, entity: Entity) -> Event

Sets the propagation to directly target the entity.

pub fn consume(&mut self)

Consumes the event to prevent it from continuing on its propagation path.

pub fn map<M, F>(&mut self, f: F)

where M: Any + Send, F: FnOnce(&M, &mut EventMeta),

Tries to downcast the event message to the specified type. If the downcast was successful, the message and the event metadata get passed into f.

Example

event.map(|app_event, _| match app_event {
    AppEvent::Increment => {
        self.count += 1;
    }

    AppEvent::Decrement => {
        self.count -= 1;
    }
});

pub fn take<M, F>(&mut self, f: F)

where M: Any + Send, F: FnOnce(M, &mut EventMeta),

Tries to downcast the event message to the specified type. If the downcast was successful, return the message by value and consume the event. Otherwise, do nothing.

Example

event.take(|app_event, meta| match app_event {
    AppEvent::Increment => {
        self.count += 1;
    }

    AppEvent::Decrement => {
        self.count -= 1;
    }
});

Trait Implementations

impl Debug for Event

fn fmt(&self, _: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.