Interface ReadonlyEventHost<EventMap>

interface ReadonlyEventHost<out EventMap> {
    hasAnyListeners(): boolean;
    hasListeners(type: keyof EventMap): boolean;
    on<K extends string | number | symbol>(
        type: K,
        handler: EventHandler<EventMap[K]>,
        options?: SignalOptions,
    ): Unsubscribe;
}

Type Parameters

out EventMap

Index

Methods

hasAnyListeners hasListeners on

Methods

hasAnyListeners

hasAnyListeners(): boolean
Returns true if the event host has any listeners.

Returns boolean
- Defined in event/EventHost.ts:44

hasListeners

hasListeners(type: keyof EventMap): boolean
Returns true if the event host has any listeners for the given type.
Parameters
- type: keyof EventMap
Returns boolean
- Defined in event/EventHost.ts:49

on

on<K extends string | number | symbol>(
    type: K,
    handler: EventHandler<EventMap[K]>,
    options?: SignalOptions,
): Unsubscribe
Adds an event handler for the given typed event.
Type Parameters
- K extends string | number | symbol
Parameters
- type: K
  The key representing the event type to listen for.
- handler: EventHandler<EventMap[K]>
  A callback to invoke when the event with the given type is dispatched.
- Optionaloptions: SignalOptions
  Options for changing listening behavior.
Returns Unsubscribe
Returns a method, when invoked, removes the handler.
- Defined in event/EventHost.ts:35