< >

Marionette.Object

A base class which other classes can extend from. Object incorporates many backbone conventions and utilities like initialize and Backbone.Events.

Documentation Index

Initialize

Initialize is called immediately after the Object has been instantiated, and is invoked with the same arguments that the constructor received.

var Friend = Marionette.Object.extend({
  initialize: function(options){
    console.log(options.name);
  }
});

new Friend({name: 'John'});

Events

Marionette.Object extends Backbone.Events and includes triggerMethod. This makes it easy for Objects to emit events that other objects can listen for with on or listenTo.

var Friend = Marionette.Object.extend({
  graduate: function() {
    this.triggerMethod('announce', 'I graduated!!!');
  }
});

var john = new Friend({name: 'John'});

john.on('announce', function(message) {
  console.log(message); // I graduated!!!
})

john.graduate();

Radio Events

Marionette.Object integrates with Backbone.Radio to provide powerful messaging capabilities. Objects can respond to both of Radio's message types; Events and Requests. The syntax is similar to the events syntax from Backbone Views, and looks like this:

radioEvents: {
  'app start': 'onAppStart',
  'books finish': 'onBooksFinish',
},

radioRequests: {
  'resources bar': 'getBar',
},

where each hash value is in the form 'channel eventName' : 'handler'. So

radioRequests: {
  'app doFoo': 'executeFoo',
},

means that the object will listen for the doFoo request on the app channel, and run the 'executeFoo' method. When using Radio Requests with Objects, the same rules and restrictions that normal Radio use implies also apply here: a single handler can be associated with a request, either through manual use of the reply functions, or through the Object API.

mergeOptions

Merge keys from the options object directly onto the instance. This is the preferred way to access options passed into the Object.

More information at mergeOptions

getOption

Retrieve an object's attribute either directly from the object, or from the object's this.options, with this.options taking precedence.

More information getOption.

bindEntityEvents

Helps bind a backbone "entity" to methods on a target object. More information bindEntityEvents.

Destroying A Object

Objects have a destroy method that unbind the events that are directly attached to the instance.

Invoking the destroy method will trigger a "before:destroy" event and corresponding onBeforeDestroy method call. These calls will be passed any arguments destroy was invoked with. Invoking destroy will return the object, this can be useful for chaining.

// define a object with an onDestroy method
var MyObject = Marionette.Object.extend({

  onBeforeDestroy: function(arg1, arg2){
    // put custom code here, to destroy this object
  }

});

// create a new object instance
var obj = new MyObject();

// add some event handlers
obj.on("before:destroy", function(arg1, arg2){ ... });
obj.listenTo(something, "bar", function(){...});

// destroy the object: unbind all of the
// event handlers, trigger the "destroy" event and
// call the onDestroy method
obj.destroy(arg1, arg2);

Basic Use

Selections is a simple Object that manages a selection of things. Because Selections extends from Object, it gets initialize and Events for free.

var Selections = Marionette.Object.extend({

  initialize: function(options){
    this.selections = {};
  },

  select: function(key, item){
    this.triggerMethod("select", key, item);
    this.selections[key] = item;
  },

  deselect: function(key, item) {
    this.triggerMethod("deselect", key, item);
    delete this.selections[key];
  }

});

var selections = new Selections({
  filters: Filters
});

// use the built in EventBinder
selections.listenTo(selections, "select", function(key, item){
  console.log(item);
});

selections.select('toy', Truck);
Improve this page