nohomey/event-listener-service

Universal Event Listener with testability built in

event-listener-service

Universal Event Listener service with testability built in

Install

Install with npm:

$ npm install event-listener-service

Api

public static useWithoutImplementation(): void

Declare usage without internal event registering implementation

public static setImplementation(implementation: EventListenerImplementation): void

Set internal event registering implementation

public static addListener(eventName: string, listener: (event?: any) => void, ...additional: any[]): void

Add EventListener

public static emit(eventName: string, emitted?: any): void

Emit event using built in event emiting

public static removeListener(eventName: string, listener: (event?: any) => void, ...additional: any[]): void

Remove EventListener

Usage

As stand alone EventListener

import EventListenerService from 'event-listener-service';

// Declare usage without internal event registering implementation
EventListenerService.useWithoutImplementation();

function onSomeEvent(event) {
  console.log('some-event', event);
}

// Adding EventLisner
EventListenerService.addListener('some-event', onSomeEvent);

// Emiting Events 
EventListenerService.emit('some-event', { rand: 9 });

// Removing EventLisnter
EventListenerService.removeListener('some-event', onSomeEvent);

For listening events on DOM Nodes in the Browser

import EventListenerService from 'event-listener-service';

// Seting internal event registering implementation
EventListenerService.setImplementation({
    addListener: window.addEventListener.bind(window),
    removeListener: window.removeEventListener.bind(window)
});

function onResize() {
  /* ... */
}

// Adding EventLisner
EventListenerService.addListener('resize', onResize, false);

// Removing EventLisnter
EventListenerService.removeListener('resize', onResize, false);

// Optionaly you can manually trigger event listeners in your tests or when you need to fully simulate event 
EventListenerService.emit('resize', /* [event object] */);

As universal EventListener API

// Set internal implementation for registering event listeners

EventListenerService.setImplementation({
    addListener: /* (eventName: string, listener: (event?: any) => void, ...additional: any[]) => void */
    removeListener: /* (eventName: string, listener: (event?: any) => void, ...additional: any[]) => void */
});

// And than use addListener and removeListner

EventListnerService.addListener(eventName: string, listener: (event?: any) => void, ...additional: any[]);

EventListnerService.removeListener(eventName: string, listener: (event?: any) => void, ...additional: any[]);

Testing

1. npm install

2. npm test

Contributing

1. npm install

2. Make changes

3. If necessary add some tests to __tests__

4. npm test

5. Make a Pull Request