ng-event-emitter v0.3.0
ngEventEmitter
This is a small library to add an event emitter functionality in AngularJS 1.x, and it contains a small factory with two methods, .on
and .triggerEvent
, written mostly because I didn't want to depend to the $rootScope or the $scope providers, but to have a much more lightweight version of event emitters.
Installation
To download the library you can do it via bower:
bower install ng-event-emitter --save
Or via NPM
npm install ng-event-emitter --save
To add to your angular project, just add the ngEventEmitter
into your module dependencies, and EventEmitter
as a dependency injection to your service/controller.
The .on(eventName, callback)
method requires two arguments, an eventName (a simple string to identify the event) and a callback function.
Multiple callbacks can be attached to the same event, and they will all be invoked once the event is triggered.
The .triggerEvent(eventName [,data])
method simply trigger the passed event, which is the only compulsory argument, a second argument can be passed to send data to the .on
method, as shown in the second example down below.
angular.module('myApp', ['ngEventEmitter'])
.service('MyService', function(EventEmitter){
this.events = new EventEmitter();
this.events.on('salute', function(){
console.log('hello world');
});
this.events.triggerEvent('salute'); // it will print `hello world` in the console
// Passing data from the triggerEvent
this.events.on('cheers', function(name){
console.log('cheers ' + name);
});
this.events.triggerEvent('cheers', 'Alex'); // it will print `cheers Alex` in the console
// Multiple callbacks for the same event
this.events.on('test', function(){
console.log('test 1');
});
this.events.on('test', function(){
console.log('test 2');
});
this.events.triggerEvent('test'); // it will print `test 1` and `test 2` in the console
// One callback for multiple events with passed data
this.events.on(['test1', 'test2'], function(name){
console.log('hello ' + name);
});
this.events.triggerEvent('test1', 'Alex'); // it will print `test Alex` in the console
this.events.triggerEvent('test2', 'Liza'); // it will print `test Liza` in the console
});
If you want to clear all the callbacks previously assigned to a specific events, you can pass the options object as a second argument, specifying clearEvent
to be true
, as shown in the example below:
this.events.on('test', function(){
console.log('test 1');
});
this.events.on('test', {clearEvent: true} function(){
console.log('test 2');
});
this.events.triggerEvent('test'); // it will print `test 2` only in the console
Unit tests
To run the unit tests, just use the command npm test
from the command line, but be sure to have ran npm install
and bower install
before to install all the dependencies needed.