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Class: Dispatcher

@ima/core.Dispatcher

A Dispatcher is a utility that manager event listeners registered for events and allows distributing (firing) events to the listeners registered for the given event.

The dispatcher provides a single-node event bus and is usually used to propagate events from controllers to UI components when modifying/passing the state is impractical for any reason.

Hierarchy

Constructors

constructor

new Dispatcher()

Methods

clear

clear(): Dispatcher

Deregisters all event listeners currently registered with this dispatcher.

Returns

Dispatcher

Defined in

packages/core/src/event/Dispatcher.ts:32


fire

fire<E>(event, data): Dispatcher

Fires a new event of the specified name, carrying the provided data.

The method will synchronously execute all event listeners registered for the specified event, passing the provided data to them as the first argument.

It will also execute all event listeners registered to listen to all events.

Note that this method does not prevent the event listeners to modify the data in any way. The order in which the event listeners will be executed is unspecified and should not be relied upon.

Type parameters

NameType
Eextends keyof DispatcherEventsMap

Parameters

NameTypeDescription
eventEThe name of the event to fire.
dataDispatcherEventsMap[E]The data to pass to the event listeners.

Returns

Dispatcher

This dispatcher.

Defined in

packages/core/src/event/Dispatcher.ts:159

fire(event, data): Dispatcher

Parameters

NameType
eventstring
dataany

Returns

Dispatcher

Defined in

packages/core/src/event/Dispatcher.ts:163


listen

listen<E>(event, listener, scope?): Dispatcher

Registers the provided event listener to be executed when the specified event is fired on this dispatcher.

When the specified event is fired, the event listener will be executed with the data passed with the event as the first argument.

The order in which the event listeners will be executed is unspecified and should not be relied upon. Registering the same listener for the same event and with the same scope multiple times has no effect.

Type parameters

NameType
Eextends keyof DispatcherEventsMap

Parameters

NameTypeDescription
eventEThe name of the event to listen for.
listenerDispatcherListener<DispatcherEventsMap[E]>The event listener to register.
scope?unknownThe object to which the this keyword will be bound in the event listener.

Returns

Dispatcher

This dispatcher.

Defined in

packages/core/src/event/Dispatcher.ts:53

listen(event, listener, scope?): Dispatcher

Parameters

NameType
eventstring
listenerDispatcherListener<any>
scope?unknown

Returns

Dispatcher

Defined in

packages/core/src/event/Dispatcher.ts:58


listenAll

listenAll<E>(listener, scope?): Dispatcher

Registers the provided event listener to be executed when any event is fired on this dispatcher.

When any event is fired, the event listener will be executed with the data passed with the event as the first argument.

The order in which the event listeners will be executed is unspecified and should not be relied upon. Registering the same listener with the same scope multiple times has no effect.

Type parameters

NameType
Eextends keyof DispatcherEventsMap

Parameters

NameTypeDescription
listenerDispatcherListenerAll<DispatcherEventsMap[E]>The event listener to register.
scope?unknownThe object to which the this keyword will be bound in the event listener.

Returns

Dispatcher

This dispatcher.

Defined in

packages/core/src/event/Dispatcher.ts:87

listenAll(listener, scope?): Dispatcher

Parameters

NameType
listenerDispatcherListenerAll<any>
scope?unknown

Returns

Dispatcher

Defined in

packages/core/src/event/Dispatcher.ts:91


unlisten

unlisten<E>(event, listener, scope?): Dispatcher

Deregisters the provided event listener, so it will no longer be executed with the specified scope when the specified event is fired.

Type parameters

NameType
Eextends keyof DispatcherEventsMap

Parameters

NameTypeDescription
eventEThe name of the event for which the listener should be deregistered.
listenerDispatcherListener<DispatcherEventsMap[E]>The event listener to deregister.
scope?unknownThe object to which the this keyword would be bound in the event listener.

Returns

Dispatcher

This dispatcher.

Defined in

packages/core/src/event/Dispatcher.ts:107

unlisten(event, listener, scope?): Dispatcher

Parameters

NameType
eventstring
listenerDispatcherListener<any>
scope?unknown

Returns

Dispatcher

Defined in

packages/core/src/event/Dispatcher.ts:112


unlistenAll

unlistenAll<E>(listener, scope?): Dispatcher

Deregisters the provided event listener, so it will no longer be executed when any event is fired.

Type parameters

NameType
Eextends keyof DispatcherEventsMap

Parameters

NameTypeDescription
listenerDispatcherListenerAll<DispatcherEventsMap[E]>The event listener function to deregister for all events.
scope?unknownOptional. The object to which the this keyword would be bound in the event listener.

Returns

Dispatcher

This dispatcher instance.

Defined in

packages/core/src/event/Dispatcher.ts:133

unlistenAll(listener, scope?): Dispatcher

Parameters

NameType
listenerDispatcherListenerAll<any>
scope?unknown

Returns

Dispatcher

Defined in

packages/core/src/event/Dispatcher.ts:137