Ember.Evented Class packages/ember-runtime/lib/mixins/evented.js:14


This mixin allows for Ember objects to subscribe to and emit events.

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App.Person = Ember.Object.extend(Ember.Evented, {
  greet: function() {
    // ...
    this.trigger('greet');
  }
});

var person = App.Person.create();

person.on('greet', function() {
  console.log('Our person has greeted');
});

person.greet();

// outputs: 'Our person has greeted'

You can also chain multiple event subscriptions:

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person.on('greet', function() {
  console.log('Our person has greeted');
}).one('greet', function() {
  console.log('Offer one-time special');
}).off('event', this, forgetThis);
Show:

Methods

Show:

has

(name) Boolean

Checks to see if object has any subscriptions for named event.

Parameters:

name String
The name of the event

Returns:

Boolean
does the object have a subscription for event

off

(name, target, method)

Cancels subscription for given name, target, and method.

Parameters:

name String
The name of the event
target Object
The target of the subscription
method Function
The function of the subscription

Returns:

this

on

(name, target, method)

Subscribes to a named event with given function.

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person.on('didLoad', function() {
  // fired once the person has loaded
});

An optional target can be passed in as the 2nd argument that will be set as the "this" for the callback. This is a good way to give your function access to the object triggering the event. When the target parameter is used the callback becomes the third argument.

Parameters:

name String
The name of the event
target [Object]
The "this" binding for the callback
method Function
The callback to execute

Returns:

this

one

(name, target, method)

Subscribes a function to a named event and then cancels the subscription after the first time the event is triggered. It is good to use one when you only care about the first time an event has taken place.

This function takes an optional 2nd argument that will become the "this" value for the callback. If this argument is passed then the 3rd argument becomes the function.

Parameters:

name String
The name of the event
target [Object]
The "this" binding for the callback
method Function
The callback to execute

Returns:

this

trigger

(name, args)

Triggers a named event for the object. Any additional arguments will be passed as parameters to the functions that are subscribed to the event.

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person.on('didEat', function(food) {
  console.log('person ate some ' + food);
});

person.trigger('didEat', 'broccoli');

// outputs: person ate some broccoli

Parameters:

name String
The name of the event
args Object...
Optional arguments to pass on