Class Ember.Application

Defined in: packages/ember-application/lib/system/application.js:28

Module: ember

An instance of Ember.Application is the starting point for every Ember application. It helps to instantiate, initialize and coordinate the many objects that make up your app.

Each Ember app has one and only one Ember.Application object. In fact, the very first thing you should do in your application is create the instance:

        
              window.App = Ember.Application.create();

Typically, the application object is the only global variable. All other classes in your app should be properties on the Ember.Application instance, which highlights its first role: a global namespace.

For example, if you define a view class, it might look like this:

        
              App.MyView = Ember.View.extend();

By default, calling Ember.Application.create() will automatically initialize your application by calling the Ember.Application.initialize() method. If you need to delay initialization, you can call your app's deferReadiness() method. When you are ready for your app to be initialized, call its advanceReadiness() method.

You can define a ready method on the Ember.Application instance, which will be run by Ember when the application is initialized.

Because Ember.Application inherits from Ember.Namespace, any classes you create will have useful string representations when calling toString(). See the Ember.Namespace documentation for more information.

While you can think of your Ember.Application as a container that holds the other classes in your application, there are several other responsibilities going on under-the-hood that you may want to understand.

Event Delegation

Ember uses a technique called event delegation. This allows the framework to set up a global, shared event listener instead of requiring each view to do it manually. For example, instead of each view registering its own mousedown listener on its associated element, Ember sets up a mousedown listener on the body.

If a mousedown event occurs, Ember will look at the target of the event and start walking up the DOM node tree, finding corresponding views and invoking their mouseDown method as it goes.

Ember.Application has a number of default events that it listens for, as well as a mapping from lowercase events to camel-cased view method names. For example, the keypress event causes the keyPress method on the view to be called, the dblclick event causes doubleClick to be called, and so on.

If there is a browser event that Ember does not listen for by default, you can specify custom events and their corresponding view method names by setting the application's customEvents property:

        
              App = Ember.Application.create({
  customEvents: {
    // add support for the loadedmetadata media
    // player event
    'loadedmetadata': "loadedMetadata"
  }
});

By default, the application sets up these event listeners on the document body. However, in cases where you are embedding an Ember application inside an existing page, you may want it to set up the listeners on an element inside the body.

For example, if only events inside a DOM element with the ID of ember-app should be delegated, set your application's rootElement property:

        
              window.App = Ember.Application.create({
  rootElement: '#ember-app'
});

The rootElement can be either a DOM element or a jQuery-compatible selector string. Note that views appended to the DOM outside the root element will not receive events. If you specify a custom root element, make sure you only append views inside it!

To learn more about the advantages of event delegation and the Ember view layer, and a list of the event listeners that are setup by default, visit the Ember View Layer guide.

Initializers

Libraries on top of Ember can register additional initializers, like so:

        
              Ember.Application.initializer({
  name: "store",

  initialize: function(container, application) {
    container.register('store:main', application.Store);
  }
});

Routing

In addition to creating your application's router, Ember.Application is also responsible for telling the router when to start routing. Transitions between routes can be logged with the LOG_TRANSITIONS flag, and more detailed intra-transition logging can be logged with the LOG_TRANSITIONS_INTERNAL flag:

        
              window.App = Ember.Application.create({
  LOG_TRANSITIONS: true, // basic logging of successful transitions
  LOG_TRANSITIONS_INTERNAL: true // detailed logging of all routing steps
});

By default, the router will begin trying to translate the current URL into application state once the browser emits the DOMContentReady event. If you need to defer routing, you can call the application's deferReadiness() method. Once routing can begin, call the advanceReadiness() method.

If there is any setup required before routing begins, you can implement a ready() method on your app that will be invoked immediately before routing begins. ```

Show: Inherited Protected Private Deprecated

addObserver (key, target, method) Ember.Object

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:312

key: String; The key to observer
target: Object; The target object to invoke
method: String|Function; The method to invoke.
returns: Ember.Object; self

Adds an observer on a property.

This is the core method used to register an observer for a property.

Once you call this method, any time the key's value is set, your observer will be notified. Note that the observers are triggered any time the value is set, regardless of whether it has actually changed. Your observer should be prepared to handle that.

You can also pass an optional context parameter to this method. The context will be passed to your observer method whenever it is triggered. Note that if you add the same target/method pair on a key multiple times with different context parameters, your observer will only be called once with the last context you passed.

Observer Methods

Observer methods you pass should generally have the following signature if you do not pass a context parameter:

        
              fooDidChange: function(sender, key, value, rev) { };

The sender is the object that changed. The key is the property that changes. The value property is currently reserved and unused. The rev is the last property revision of the object when it changed, which you can use to detect if the key value has really changed or not.

If you pass a context parameter, the context will be passed before the revision like so:

        
              fooDidChange: function(sender, key, value, context, rev) { };

Usually you will not need the value, context or revision parameters at the end. In this case, it is common to write observer methods that take only a sender and key value as parameters or, if you aren't interested in any of these values, to write an observer that has no parameters at all.

advanceReadiness

Module: ember

Defined in packages/ember-application/lib/system/application.js:356

Call advanceReadiness after any asynchronous setup logic has completed. Each call to deferReadiness must be matched by a call to advanceReadiness or the application will never become ready and routing will not begin.

beginPropertyChanges Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:211

returns: Ember.Observable

Begins a grouping of property changes.

You can use this method to group property changes so that notifications will not be sent until the changes are finished. If you plan to make a large number of changes to an object at one time, you should call this method at the beginning of the changes to begin deferring change notifications. When you are done making changes, call endPropertyChanges() to deliver the deferred change notifications and end deferring.

cacheFor (keyName) Object

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:490

keyName: String
returns: Object; The cached value of the computed property, if any

Returns the cached value of a computed property, if it exists. This allows you to inspect the value of a computed property without accidentally invoking it if it is intended to be generated lazily.

create (arguments)

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:435

arguments

Creates an instance of a class. Accepts either no arguments, or an object containing values to initialize the newly instantiated object with.

        
              App.Person = Ember.Object.extend({
  helloWorld: function() {
    alert("Hi, my name is " + this.get('name'));
  }
});

var tom = App.Person.create({
  name: 'Tom Dale'
});

tom.helloWorld(); // alerts "Hi, my name is Tom Dale".

create will call the init function if defined during Ember.AnyObject.extend

If no arguments are passed to create, it will not set values to the new instance during initialization:

        
              var noName = App.Person.create();
noName.helloWorld(); // alerts undefined

NOTE: For performance reasons, you cannot declare methods or computed properties during create. You should instead declare methods and computed properties when using extend or use the createWithMixins shorthand.

createWithMixins (arguments)

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:421

arguments

Equivalent to doing extend(arguments).create(). If possible use the normal create method instead.

decrementProperty (keyName, decrement) Number

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:453

keyName: String; The name of the property to decrement
decrement: Number; The amount to decrement by. Defaults to 1
returns: Number; The new property value

Set the value of a property to the current value minus some amount.

        
              player.decrementProperty('lives');
orc.decrementProperty('health', 5);

deferReadiness

Module: ember

Defined in packages/ember-application/lib/system/application.js:327

Use this to defer readiness until some condition is true.

Example:

        
              App = Ember.Application.create();
App.deferReadiness();

jQuery.getJSON("/auth-token", function(token) {
  App.token = token;
  App.advanceReadiness();
});

This allows you to perform asynchronous setup logic and defer booting your application until the setup has finished.

However, if the setup requires a loading UI, it might be better to use the router for this purpose.

destroy Ember.Object

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:289

returns: Ember.Object; receiver

Destroys an object by setting the isDestroyed flag and removing its metadata, which effectively destroys observers and bindings.

If you try to set a property on a destroyed object, an exception will be raised.

Note that destruction is scheduled for the end of the run loop and does not happen immediately. It will set an isDestroying flag immediately.

eachComputedProperty (callback, binding)

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:590

callback: Function
binding: Object

Iterate over each computed property for the class, passing its name and any associated metadata (see metaForProperty) to the callback.

endPropertyChanges Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:230

returns: Ember.Observable

Ends a grouping of property changes.

You can use this method to group property changes so that notifications will not be sent until the changes are finished. If you plan to make a large number of changes to an object at one time, you should call beginPropertyChanges() at the beginning of the changes to defer change notifications. When you are done making changes, call this method to deliver the deferred change notifications and end deferring.

get (keyName) Object

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:78

keyName: String; The property to retrieve
returns: Object; The property value or undefined.

Retrieves the value of a property from the object.

This method is usually similar to using object[keyName] or object.keyName, however it supports both computed properties and the unknownProperty handler.

Because get unifies the syntax for accessing all these kinds of properties, it can make many refactorings easier, such as replacing a simple property with a computed property, or vice versa.

Computed Properties

Computed properties are methods defined with the property modifier declared at the end, such as:

        
              fullName: function() {
  return this.getEach('firstName', 'lastName').compact().join(' ');
}.property('firstName', 'lastName')

When you call get on a computed property, the function will be called and the return value will be returned instead of the function itself.

Unknown Properties

Likewise, if you try to call get on a property whose value is undefined, the unknownProperty() method will be called on the object. If this method returns any value other than undefined, it will be returned instead. This allows you to implement "virtual" properties that are not defined upfront.

getProperties (list) Hash

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:120

list: String...|Array; of keys to get
returns: Hash

To get multiple properties at once, call getProperties with a list of strings or an array:

        
              record.getProperties('firstName', 'lastName', 'zipCode');  // { firstName: 'John', lastName: 'Doe', zipCode: '10011' }

is equivalent to:

        
              record.getProperties(['firstName', 'lastName', 'zipCode']);  // { firstName: 'John', lastName: 'Doe', zipCode: '10011' }

getWithDefault (keyName, defaultValue) Object

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:416

keyName: String; The name of the property to retrieve
defaultValue: Object; The value to return if the property value is undefined
returns: Object; The property value or the defaultValue.

Retrieves the value of a property, or a default value in the case that the property returns undefined.

        
              person.getWithDefault('lastName', 'Doe');

hasObserverFor (key) Boolean

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:379

key: String; Key to check
returns: Boolean

Returns true if the object currently has observers registered for a particular key. You can use this method to potentially defer performing an expensive action until someone begins observing a particular property on the object.

incrementProperty (keyName, increment) Number

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:433

keyName: String; The name of the property to increment
increment: Number; The amount to increment by. Defaults to 1
returns: Number; The new property value

Set the value of a property to the current value plus some amount.

        
              person.incrementProperty('age');
team.incrementProperty('score', 2);

init

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:171

An overridable method called when objects are instantiated. By default, does nothing unless it is overridden during class definition.

Example:

        
              App.Person = Ember.Object.extend({
  init: function() {
    this._super();
    alert('Name is ' + this.get('name'));
  }
});

var steve = App.Person.create({
  name: "Steve"
});

// alerts 'Name is Steve'.

NOTE: If you do override init for a framework class like Ember.View or Ember.ArrayController, be sure to call this._super() in your init declaration! If you don't, Ember may not have an opportunity to do important setup work, and you'll see strange behavior in your application.

inject (factoryNameOrType, property, injectionName)

Module: ember

Defined in packages/ember-application/lib/system/application.js:400

factoryNameOrType: String
property: String
injectionName: String

defines an injection or typeInjection

Example:

        
              App.inject(<full_name or type>, <property name>, <full_name>)
App.inject('model:user', 'email', 'model:email')
App.inject('model', 'source', 'source:main')

metaForProperty (key)

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:556

key: String; property name

In some cases, you may want to annotate computed properties with additional metadata about how they function or what values they operate on. For example, computed property functions may close over variables that are then no longer available for introspection.

You can pass a hash of these values to a computed property like this:

        
              person: function() {
  var personId = this.get('personId');
  return App.Person.create({ id: personId });
}.property().meta({ type: App.Person })

Once you've done this, you can retrieve the values saved to the computed property from your class like this:

        
              MyClass.metaForProperty('person');

This will return the original hash that was passed to meta().

notifyPropertyChange (keyName) Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:294

keyName: String; The property key to be notified about.
returns: Ember.Observable

Convenience method to call propertyWillChange and propertyDidChange in succession.

propertyDidChange (keyName) Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:271

keyName: String; The property key that has just changed.
returns: Ember.Observable

Notify the observer system that a property has just changed.

Sometimes you need to change a value directly or indirectly without actually calling get() or set() on it. In this case, you can use this method and propertyWillChange() instead. Calling these two methods together will notify all observers that the property has potentially changed value.

Note that you must always call propertyWillChange and propertyDidChange as a pair. If you do not, it may get the property change groups out of order and cause notifications to be delivered more often than you would like.

propertyWillChange (keyName) Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:248

keyName: String; The property key that is about to change.
returns: Ember.Observable

Notify the observer system that a property is about to change.

Sometimes you need to change a value directly or indirectly without actually calling get() or set() on it. In this case, you can use this method and propertyDidChange() instead. Calling these two methods together will notify all observers that the property has potentially changed value.

register (type, name, factory, options)

Module: ember

Defined in packages/ember-application/lib/system/application.js:373

type: String
name: String
factory: String
options: String; (optional)

registers a factory for later injection

Example:

        
              App = Ember.Application.create();

App.Person = Ember.Object.extend({});
App.Orange = Ember.Object.extend({});
App.Email  = Ember.Object.extend({});

App.register('model:user', App.Person, {singleton: false });
App.register('fruit:favorite', App.Orange);
App.register('communication:main', App.Email, {singleton: false});

removeObserver (key, target, method) Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:364

key: String; The key to observer
target: Object; The target object to invoke
method: String|Function; The method to invoke.
returns: Ember.Observable; receiver

Remove an observer you have previously registered on this object. Pass the same key, target, and method you passed to addObserver() and your target will no longer receive notifications.

reopen

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:478

Augments a constructor's prototype with additional properties and functions:

```javascript MyObject = Ember.Object.extend({ name: 'an object' });

        
              o = MyObject.create();
o.get('name'); // 'an object'

MyObject.reopen({
  say: function(msg){
    console.log(msg);
  }
})

o2 = MyObject.create();
o2.say("hello"); // logs "hello"

o.say("goodbye"); // logs "goodbye"
```

To add functions and properties to the constructor itself, see reopenClass

reopenClass

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:514

Augments a constructor's own properties and functions:

        
              MyObject = Ember.Object.extend({
  name: 'an object'
});

MyObject.reopenClass({
  canBuild: false
});

MyObject.canBuild; // false
o = MyObject.create();

To add functions and properties to instances of a constructor by extending the constructor's prototype see reopen

reset

Module: ember

Defined in packages/ember-application/lib/system/application.js:463

Reset the application. This is typically used only in tests. It cleans up the application in the following order:

Deactivate existing routes
Destroy all objects in the container
Create a new application container
Re-route to the existing url

Typical Example:

        
              var App;

Ember.run(function() {
  App = Ember.Application.create();
});

module("acceptance test", {
  setup: function() {
    App.reset();
  }
});

test("first test", function() {
  // App is freshly reset
});

test("first test", function() {
  // App is again freshly reset
});

Advanced Example:

Occasionally you may want to prevent the app from initializing during setup. This could enable extra configuration, or enable asserting prior to the app becoming ready.

        
          
              
              var App;

Ember.run(function() {
  App = Ember.Application.create();
});

module("acceptance test", {
  setup: function() {
    Ember.run(function() {
      App.reset();
      App.deferReadiness();
    });
  }
});

test("first test", function() {
  ok(true, 'something before app is initialized');

  Ember.run(function() {
    App.advanceReadiness();
  });
  ok(true, 'something after app is initialized');
});
            

        
      

set (keyName, value) Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:142

keyName: String; The property to set
value: Object; The value to set or `null`.
returns: Ember.Observable

Sets the provided key or path to the value.

This method is generally very similar to calling object[key] = value or object.key = value, except that it provides support for computed properties, the setUnknownProperty() method and property observers.

Computed Properties

If you try to set a value on a key that has a computed property handler defined (see the get() method for an example), then set() will call that method, passing both the value and key instead of simply changing the value itself. This is useful for those times when you need to implement a property that is composed of one or more member properties.

Unknown Properties

If you try to set a value on a key that is undefined in the target object, then the setUnknownProperty() handler will be called instead. This gives you an opportunity to implement complex "virtual" properties that are not predefined on the object. If setUnknownProperty() returns undefined, then set() will simply set the value on the object.

Property Observers

In addition to changing the property, set() will also register a property change with the object. Unless you have placed this call inside of a beginPropertyChanges() and endPropertyChanges(), any "local" observers (i.e. observer methods declared on the same object), will be called immediately. Any "remote" observers (i.e. observer methods declared on another object) will be placed in a queue and called at a later time in a coalesced manner.

Chaining

In addition to property changes, set() returns the value of the object itself so you can do chaining like this:

        
              record.set('firstName', 'Charles').set('lastName', 'Jolley');

setProperties (hash) Ember.Observable

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:195

hash: Hash; the hash of keys and values to set
returns: Ember.Observable

To set multiple properties at once, call setProperties with a Hash:

        
              record.setProperties({ firstName: 'Charles', lastName: 'Jolley' });

toString String

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:338

returns: String; string representation

Returns a string representation which attempts to provide more information than Javascript's toString typically does, in a generic way for all Ember objects.

        
              App.Person = Em.Object.extend()
person = App.Person.create()
person.toString() //=> "<App.Person:ember1024>"

If the object's class is not defined on an Ember namespace, it will indicate it is a subclass of the registered superclass:

        
              Student = App.Person.extend()
student = Student.create()
student.toString() //=> "<(subclass of App.Person):ember1025>"

If the method toStringExtension is defined, its return value will be included in the output.

        
              App.Teacher = App.Person.extend({
  toStringExtension: function() {
    return this.get('fullName');
  }
});
teacher = App.Teacher.create()
teacher.toString(); //=> "<App.Teacher:ember1026:Tom Dale>"

toggleProperty (keyName) Object

Module: ember

Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:473

keyName: String; The name of the property to toggle
returns: Object; The new property value

Set the value of a boolean property to the opposite of it's current value.

        
              starship.toggleProperty('warpDriveEngaged');

willDestroy

Module: ember

Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:311

Override to implement teardown.