Ember.Application Class packages/ember-application/lib/system/application.js:49


PUBLIC

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:

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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:

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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 bubbling 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:

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let App = Ember.Application.create({
  customEvents: {
    // add support for the paste event
    paste: 'paste'
  }
});

To prevent Ember from setting up a listener for a default event, specify the event name with a null value in the customEvents property:

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let App = Ember.Application.create({
  customEvents: {
    // prevent listeners for mouseenter/mouseleave events
    mouseenter: null,
    mouseleave: null
  }
});

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:

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let 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 events Ember components use, see components/handling-events.

Initializers

Libraries on top of Ember can add initializers, like so:

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Ember.Application.initializer({
  name: 'api-adapter',

  initialize: function(application) {
    application.register('api-adapter:main', ApiAdapter);
  }
});

Initializers provide an opportunity to access the internal registry, which organizes the different components of an Ember application. Additionally they provide a chance to access the instantiated application. Beyond being used for libraries, initializers are also a great way to organize dependency injection or setup in your own application.

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:

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let 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:

_lazyInjections

Object private

Returns a hash of property names and container names that injected properties will lookup on the container lazily.

Returns:

Object
Hash of all lazy injected property keys to container names

_onLookup

private

Provides lookup-time type validation for injected properties.

_prepareForGlobalsMode

private

Enable the legacy globals mode by allowing this application to act as a global namespace. See the docs on the _globalsMode property for details.

Most of these features are already deprecated in 1.x, so we can stop using them internally and try to remove them.

_scheduledDestroy

private

Invoked by the run loop to actually destroy the object. This is scheduled for execution by the destroy method.

addObserver

(key, target, method) public

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:

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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:

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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.

Parameters:

key String
The key to observer
target Object
The target object to invoke
method String|Function
The method to invoke.

advanceReadiness

public

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 private

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.

Returns:

Ember.Observable

boot

Promise private

Initialize the application and return a promise that resolves with the Ember.Application object when the boot process is complete.

Run any application initializers and run the application load hook. These hooks may choose to defer readiness. For example, an authentication hook might want to defer readiness until the auth token has been retrieved.

By default, this method is called automatically on "DOM ready"; however, if autoboot is disabled, this is automatically called when the first application instance is created via visit.

Returns:

Promise

buildInstance

Ember.ApplicationInstance private

Create an ApplicationInstance for this application.

Returns:

Ember.ApplicationInstance
the application instance

buildRegistry

(namespace) Ember.Registry private static

This creates a registry with the default Ember naming conventions.

It also configures the registry:

  • registered views are created every time they are looked up (they are not singletons)
  • registered templates are not factories; the registered value is returned directly.
  • the router receives the application as its namespace property
  • all controllers receive the router as their target and controllers properties
  • all controllers receive the application as their namespace property
  • the application view receives the application controller as its controller property
  • the application view receives the application template as its defaultTemplate property

Parameters:

namespace Ember.Application
the application for which to build the registry

Returns:

Ember.Registry
the built registry

cacheFor

(keyName) Object public

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.

Parameters:

keyName String

Returns:

Object
The cached value of the computed property, if any

create

(arguments) public static

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

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const Person = Ember.Object.extend({
  helloWorld() {
    alert(`Hi, my name is ${this.get('name')}`);
  }
});

let tom = 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:

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let noName = 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.

Parameters:

arguments []

decrementProperty

(keyName, decrement) Number public

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

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

Parameters:

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

deferReadiness

public

Use this to defer readiness until some condition is true.

Example:

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let App = Ember.Application.create();

App.deferReadiness();

// Ember.$ is a reference to the jQuery object/function
Ember.$.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 public

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.

Returns:

Ember.Object
receiver

didBecomeReady

private

domReady

private

This is the autoboot flow:

  1. Boot the app by calling this.boot()
  2. Create an instance (or use the __deprecatedInstance__ in globals mode)
  3. Boot the instance by calling instance.boot()
  4. Invoke the App.ready() callback
  5. Kick-off routing on the instance

Ideally, this is all we would need to do:

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_autoBoot() {
  this.boot().then(() => {
    let instance = (this._globalsMode) ? this.__deprecatedInstance__ : this.buildInstance();
    return instance.boot();
  }).then((instance) => {
    App.ready();
    instance.startRouting();
  });
}

Unfortunately, we cannot actually write this because we need to participate in the "synchronous" boot process. While the code above would work fine on the initial boot (i.e. DOM ready), when App.reset() is called, we need to boot a new instance synchronously (see the documentation on _bootSync() for details).

Because of this restriction, the actual logic of this method is located inside didBecomeReady().

eachComputedProperty

(callback, binding) private static

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

Parameters:

callback Function
binding Object

endPropertyChanges

Ember.Observable private

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.

Returns:

Ember.Observable

ensureInitializers

private

Ensure that initializers are run once, and only once, per engine.

extend

(mixins, arguments) public static

Creates a new subclass.

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const Person = Ember.Object.extend({
  say(thing) {
    alert(thing);
   }
});

This defines a new subclass of Ember.Object: Person. It contains one method: say().

You can also create a subclass from any existing class by calling its extend() method. For example, you might want to create a subclass of Ember's built-in Ember.Component class:

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const PersonComponent = Ember.Component.extend({
  tagName: 'li',
  classNameBindings: ['isAdministrator']
});

When defining a subclass, you can override methods but still access the implementation of your parent class by calling the special _super() method:

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const Person = Ember.Object.extend({
  say(thing) {
    var name = this.get('name');
    alert(`${name} says: ${thing}`);
  }
});

const Soldier = Person.extend({
  say(thing) {
    this._super(`${thing}, sir!`);
  },
  march(numberOfHours) {
    alert(`${this.get('name')} marches for ${numberOfHours} hours.`);
  }
});

let yehuda = Soldier.create({
  name: "Yehuda Katz"
});

yehuda.say("Yes");  // alerts "Yehuda Katz says: Yes, sir!"

The create() on line #17 creates an instance of the Soldier class. The extend() on line #8 creates a subclass of Person. Any instance of the Person class will not have the march() method.

You can also pass Mixin classes to add additional properties to the subclass.

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const Person = Ember.Object.extend({
  say(thing) {
    alert(`${this.get('name')} says: ${thing}`);
  }
});

const SingingMixin = Mixin.create({
  sing(thing){
    alert(`${this.get('name')} sings: la la la ${thing}`);
  }
});

const BroadwayStar = Person.extend(SingingMixin, {
  dance() {
    alert(`${this.get('name')} dances: tap tap tap tap `);
  }
});

The BroadwayStar class contains three methods: say(), sing(), and dance().

Parameters:

mixins [Mixin]
One or more Mixin classes
arguments [Object]
Object containing values to use within the new class

get

(keyName) Object public

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:

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fullName: Ember.computed('firstName', 'lastName', function() {
  return this.get('firstName') + ' ' + this.get('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.

Parameters:

keyName String
The property to retrieve

Returns:

Object
The property value or undefined.

getProperties

(list) Object public

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

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

is equivalent to:

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

Parameters:

list String...|Array
of keys to get

Returns:

Object

getWithDefault

(keyName, defaultValue) Object public

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

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

Parameters:

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.

hasObserverFor

(key) Boolean private

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.

Parameters:

key String
Key to check

Returns:

Boolean

hasRegistration

(fullName) Boolean public

Check if a factory is registered.

Parameters:

fullName String

Returns:

Boolean

incrementProperty

(keyName, increment) Number public

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

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

Parameters:

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

init

public

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

Example:

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const Person = Ember.Object.extend({
  init() {
    alert(`Name is ${this.get('name')}`);
  }
});

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

// alerts 'Name is Steve'.

NOTE: If you do override init for a framework class like Ember.View, be sure to call this._super(...arguments) 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.

initializer

(initializer) public

The goal of initializers should be to register dependencies and injections. This phase runs once. Because these initializers may load code, they are allowed to defer application readiness and advance it. If you need to access the container or store you should use an InstanceInitializer that will be run after all initializers and therefore after all code is loaded and the app is ready.

Initializer receives an object which has the following attributes: name, before, after, initialize. The only required attribute is initialize, all others are optional.

  • name allows you to specify under which name the initializer is registered. This must be a unique name, as trying to register two initializers with the same name will result in an error.
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Ember.Application.initializer({
  name: 'namedInitializer',

  initialize: function(application) {
    Ember.debug('Running namedInitializer!');
  }
});
  • before and after are used to ensure that this initializer is ran prior or after the one identified by the value. This value can be a single string or an array of strings, referencing the name of other initializers.

An example of ordering initializers, we create an initializer named first:

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Ember.Application.initializer({
  name: 'first',

  initialize: function(application) {
    Ember.debug('First initializer!');
  }
});

// DEBUG: First initializer!

We add another initializer named second, specifying that it should run after the initializer named first:

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Ember.Application.initializer({
  name: 'second',
  after: 'first',

  initialize: function(application) {
    Ember.debug('Second initializer!');
  }
});

// DEBUG: First initializer!
// DEBUG: Second initializer!

Afterwards we add a further initializer named pre, this time specifying that it should run before the initializer named first:

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Ember.Application.initializer({
  name: 'pre',
  before: 'first',

  initialize: function(application) {
    Ember.debug('Pre initializer!');
  }
});

// DEBUG: Pre initializer!
// DEBUG: First initializer!
// DEBUG: Second initializer!

Finally we add an initializer named post, specifying it should run after both the first and the second initializers:

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Ember.Application.initializer({
  name: 'post',
  after: ['first', 'second'],

  initialize: function(application) {
    Ember.debug('Post initializer!');
  }
});

// DEBUG: Pre initializer!
// DEBUG: First initializer!
// DEBUG: Second initializer!
// DEBUG: Post initializer!
  • initialize is a callback function that receives one argument, application, on which you can operate.

Example of using application to register an adapter:

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Ember.Application.initializer({
  name: 'api-adapter',

  initialize: function(application) {
    application.register('api-adapter:main', ApiAdapter);
  }
});

Parameters:

initializer Object

inject

(factoryNameOrType, property, injectionName) public

Define a dependency injection onto a specific factory or all factories of a type.

When Ember instantiates a controller, view, or other framework component it can attach a dependency to that component. This is often used to provide services to a set of framework components.

An example of providing a session object to all controllers:

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let App = Ember.Application.create();
let Session = Ember.Object.extend({ isAuthenticated: false });

// A factory must be registered before it can be injected
App.register('session:main', Session);

// Inject 'session:main' onto all factories of the type 'controller'
// with the name 'session'
App.inject('controller', 'session', 'session:main');

App.IndexController = Ember.Controller.extend({
  isLoggedIn: Ember.computed.alias('session.isAuthenticated')
});

Injections can also be performed on specific factories.

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

It is important to note that injections can only be performed on classes that are instantiated by Ember itself. Instantiating a class directly (via create or new) bypasses the dependency injection system.

Note: Ember-Data instantiates its models in a unique manner, and consequently injections onto models (or all models) will not work as expected. Injections on models can be enabled by setting EmberENV.MODEL_FACTORY_INJECTIONS to true.

Parameters:

factoryNameOrType String
property String
injectionName String

instanceInitializer

(instanceInitializer) public

Instance initializers run after all initializers have run. Because instance initializers run after the app is fully set up. We have access to the store, container, and other items. However, these initializers run after code has loaded and are not allowed to defer readiness.

Instance initializer receives an object which has the following attributes: name, before, after, initialize. The only required attribute is initialize, all others are optional.

  • name allows you to specify under which name the instanceInitializer is registered. This must be a unique name, as trying to register two instanceInitializer with the same name will result in an error.
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Ember.Application.instanceInitializer({
  name: 'namedinstanceInitializer',

  initialize: function(application) {
    Ember.debug('Running namedInitializer!');
  }
});
  • before and after are used to ensure that this initializer is ran prior or after the one identified by the value. This value can be a single string or an array of strings, referencing the name of other initializers.

  • See Ember.Application.initializer for discussion on the usage of before and after.

Example instanceInitializer to preload data into the store.

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Ember.Application.initializer({
  name: 'preload-data',

  initialize: function(application) {
    var userConfig, userConfigEncoded, store;
    // We have a HTML escaped JSON representation of the user's basic
    // configuration generated server side and stored in the DOM of the main
    // index.html file. This allows the app to have access to a set of data
    // without making any additional remote calls. Good for basic data that is
    // needed for immediate rendering of the page. Keep in mind, this data,
    // like all local models and data can be manipulated by the user, so it
    // should not be relied upon for security or authorization.
    //
    // Grab the encoded data from the meta tag
    userConfigEncoded = Ember.$('head meta[name=app-user-config]').attr('content');
    // Unescape the text, then parse the resulting JSON into a real object
    userConfig = JSON.parse(unescape(userConfigEncoded));
    // Lookup the store
    store = application.lookup('service:store');
    // Push the encoded JSON into the store
    store.pushPayload(userConfig);
  }
});

Parameters:

instanceInitializer

metaForProperty

(key) private static

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:

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

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

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MyClass.metaForProperty('person');

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

Parameters:

key String
property name

notifyPropertyChange

(keyName) Ember.Observable public

Convenience method to call propertyWillChange and propertyDidChange in succession.

Parameters:

keyName String
The property key to be notified about.

Returns:

Ember.Observable

propertyDidChange

(keyName) Ember.Observable private

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.

Parameters:

keyName String
The property key that has just changed.

Returns:

Ember.Observable

propertyWillChange

(keyName) Ember.Observable private

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.

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.

Parameters:

keyName String
The property key that is about to change.

Returns:

Ember.Observable

register

(fullName, factory, options) public

Registers a factory that can be used for dependency injection (with inject) or for service lookup. Each factory is registered with a full name including two parts: type:name.

A simple example:

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let App = Ember.Application.create();

App.Orange = Ember.Object.extend();
App.register('fruit:favorite', App.Orange);

Ember will resolve factories from the App namespace automatically. For example App.CarsController will be discovered and returned if an application requests controller:cars.

An example of registering a controller with a non-standard name:

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let App = Ember.Application.create();
let Session = Ember.Controller.extend();

App.register('controller:session', Session);

// The Session controller can now be treated like a normal controller,
// despite its non-standard name.
App.ApplicationController = Ember.Controller.extend({
  needs: ['session']
});

Registered factories are instantiated by having create called on them. Additionally they are singletons, each time they are looked up they return the same instance.

Some examples modifying that default behavior:

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let App = Ember.Application.create();

App.Person = Ember.Object.extend();
App.Orange = Ember.Object.extend();
App.Email = Ember.Object.extend();
App.session = Ember.Object.create();

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

Parameters:

fullName String
type:name (e.g., 'model:user')
factory Function
(e.g., App.Person)
options Object
(optional) disable instantiation or singleton usage

registerOption

(fullName, optionName, options) public

Register an option for a particular factory.

Parameters:

fullName String
optionName String
options Object

registerOptions

(fullName, options) public

Register options for a particular factory.

Parameters:

fullName String
options Object

registerOptionsForType

(type, options) public

Allow registering options for all factories of a type.

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let App = Ember.Application.create();
let appInstance = App.buildInstance();

// if all of type `connection` must not be singletons
appInstance.optionsForType('connection', { singleton: false });

appInstance.register('connection:twitter', TwitterConnection);
appInstance.register('connection:facebook', FacebookConnection);

let twitter = appInstance.lookup('connection:twitter');
let twitter2 = appInstance.lookup('connection:twitter');

twitter === twitter2; // => false

let facebook = appInstance.lookup('connection:facebook');
let facebook2 = appInstance.lookup('connection:facebook');

facebook === facebook2; // => false

Parameters:

type String
options Object

registeredOption

(fullName, optionName) Object public

Return a specific registered option for a particular factory.

Parameters:

fullName String
optionName String

Returns:

Object
options

registeredOptions

(fullName) Object public

Return registered options for a particular factory.

Parameters:

fullName String

Returns:

Object
options

registeredOptionsForType

(type) Object public

Return the registered options for all factories of a type.

Parameters:

type String

Returns:

Object
options

removeObserver

(key, target, method) public

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.

Parameters:

key String
The key to observer
target Object
The target object to invoke
method String|Function
The method to invoke.

reopen

public

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

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

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

MyObject.reopen({
  say(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

public

Augments a constructor's own properties and functions:

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

MyObject.reopenClass({
  canBuild: false
});

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

In other words, this creates static properties and functions for the class. These are only available on the class and not on any instance of that class.

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const Person = Ember.Object.extend({
  name: "",
  sayHello() {
    alert("Hello. My name is " + this.get('name'));
  }
});

Person.reopenClass({
  species: "Homo sapiens",
  createPerson(newPersonsName){
    return Person.create({
      name:newPersonsName
    });
  }
});

let tom = Person.create({
  name: "Tom Dale"
});
let yehuda = Person.createPerson("Yehuda Katz");

tom.sayHello(); // "Hello. My name is Tom Dale"
yehuda.sayHello(); // "Hello. My name is Yehuda Katz"
alert(Person.species); // "Homo sapiens"

Note that species and createPerson are not valid on the tom and yehuda variables. They are only valid on Person.

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

reset

public

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

  1. Deactivate existing routes
  2. Destroy all objects in the container
  3. Create a new application container
  4. Re-route to the existing url

Typical Example:

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let App;

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

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

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

test('second 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.

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let App;

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

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

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

  run(function() {
    App.advanceReadiness();
  });

  ok(true, 'something after app is initialized');
});

resolveRegistration

(fullName) Function public

Given a fullName return the corresponding factory.

Parameters:

fullName String

Returns:

Function
fullName's factory

resolverFor

(namespace) * private

This function defines the default lookup rules for container lookups:

  • templates are looked up on Ember.TEMPLATES
  • other names are looked up on the application after classifying the name. For example, controller:post looks up App.PostController by default.
  • if the default lookup fails, look for registered classes on the container

This allows the application to register default injections in the container that could be overridden by the normal naming convention.

Parameters:

namespace Ember.Namespace
the namespace to look for classes

Returns:

*
the resolved value for a given lookup

runInitializers

private

runInstanceInitializers

private

set

(keyName, value) Object public

Sets the provided key or path to the value.

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record.set("key", 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.

Parameters:

keyName String
The property to set
value Object
The value to set or `null`.

Returns:

Object
The passed value

setProperties

(hash) Object public

Sets a list of properties at once. These properties are set inside a single beginPropertyChanges and endPropertyChanges batch, so observers will be buffered.

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

Parameters:

hash Object
the hash of keys and values to set

Returns:

Object
The passed in hash

toString

String public

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

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const Person = Ember.Object.extend()
person = Person.create()
person.toString() //=> "<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:

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

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

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

Returns:

String
string representation

toggleProperty

(keyName) Boolean public

Set the value of a boolean property to the opposite of its current value.

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Parameters:

keyName String
The name of the property to toggle

Returns:

Boolean
The new property value

unregister

(fullName) public

Unregister a factory.

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let App = Ember.Application.create();
let User = Ember.Object.extend();
App.register('model:user', User);

App.resolveRegistration('model:user').create() instanceof User //=> true

App.unregister('model:user')
App.resolveRegistration('model:user') === undefined //=> true

Parameters:

fullName String

visit

(url, options) Promise public

Boot a new instance of Ember.ApplicationInstance for the current application and navigate it to the given url. Returns a Promise that resolves with the instance when the initial routing and rendering is complete, or rejects with any error that occured during the boot process.

When autoboot is disabled, calling visit would first cause the application to boot, which runs the application initializers.

This method also takes a hash of boot-time configuration options for customizing the instance's behavior. See the documentation on Ember.ApplicationInstance.BootOptions for details.

Ember.ApplicationInstance.BootOptions is an interface class that exists purely to document the available options; you do not need to construct it manually. Simply pass a regular JavaScript object containing of the desired options:

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MyApp.visit("/", { location: "none", rootElement: "#container" });

Supported Scenarios

While the BootOptions class exposes a large number of knobs, not all combinations of them are valid; certain incompatible combinations might result in unexpected behavior.

For example, booting the instance in the full browser environment while specifying a foriegn document object (e.g. { isBrowser: true, document: iframe.contentDocument }) does not work correctly today, largely due to Ember's jQuery dependency.

Currently, there are three officially supported scenarios/configurations. Usages outside of these scenarios are not guaranteed to work, but please feel free to file bug reports documenting your experience and any issues you encountered to help expand support.

Browser Applications (Manual Boot)

The setup is largely similar to how Ember works out-of-the-box. Normally, Ember will boot a default instance for your Application on "DOM ready". However, you can customize this behavior by disabling autoboot.

For example, this allows you to render a miniture demo of your application into a specific area on your marketing website:

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import MyApp from 'my-app';

$(function() {
  let App = MyApp.create({ autoboot: false });

  let options = {
    // Override the router's location adapter to prevent it from updating
    // the URL in the address bar
    location: 'none',

    // Override the default `rootElement` on the app to render into a
    // specific `div` on the page
    rootElement: '#demo'
  };

  // Start the app at the special demo URL
  App.visit('/demo', options);
});

Or perhaps you might want to boot two instances of your app on the same page for a split-screen multiplayer experience:

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import MyApp from 'my-app';

$(function() {
  let App = MyApp.create({ autoboot: false });

  let sessionId = MyApp.generateSessionID();

  let player1 = App.visit(`/matches/join?name=Player+1&session=${sessionId}`, { rootElement: '#left', location: 'none' });
  let player2 = App.visit(`/matches/join?name=Player+2&session=${sessionId}`, { rootElement: '#right', location: 'none' });

  Promise.all([player1, player2]).then(() => {
    // Both apps have completed the initial render
    $('#loading').fadeOut();
  });
});

Do note that each app instance maintains their own registry/container, so they will run in complete isolation by default.

Server-Side Rendering (also known as FastBoot)

This setup allows you to run your Ember app in a server environment using Node.js and render its content into static HTML for SEO purposes.

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const HTMLSerializer = new SimpleDOM.HTMLSerializer(SimpleDOM.voidMap);

function renderURL(url) {
  let dom = new SimpleDOM.Document();
  let rootElement = dom.body;
  let options = { isBrowser: false, document: dom, rootElement: rootElement };

  return MyApp.visit(options).then(instance => {
    try {
      return HTMLSerializer.serialize(rootElement.firstChild);
    } finally {
      instance.destroy();
    }
  });
}

In this scenario, because Ember does not have access to a global document object in the Node.js environment, you must provide one explicitly. In practice, in the non-browser environment, the stand-in document object only need to implement a limited subset of the full DOM API. The SimpleDOM library is known to work.

Since there is no access to jQuery in the non-browser environment, you must also specify a DOM Element object in the same document for the rootElement option (as opposed to a selector string like "body").

See the documentation on the isBrowser, document and rootElement properties on Ember.ApplicationInstance.BootOptions for details.

Server-Side Resource Discovery

This setup allows you to run the routing layer of your Ember app in a server environment using Node.js and completely disable rendering. This allows you to simulate and discover the resources (i.e. AJAX requests) needed to fufill a given request and eagerly "push" these resources to the client.

app/initializers/network-service.js
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import BrowserNetworkService from 'app/services/network/browser';
import NodeNetworkService from 'app/services/network/node';

// Inject a (hypothetical) service for abstracting all AJAX calls and use
// the appropiate implementaion on the client/server. This also allows the
// server to log all the AJAX calls made during a particular request and use
// that for resource-discovery purpose.

export function initialize(application) {
  if (window) { // browser
    application.register('service:network', BrowserNetworkService);
  } else { // node
    application.register('service:network', NodeNetworkService);
  }

  application.inject('route', 'network', 'service:network');
};

export default {
  name: 'network-service',
  initialize: initialize
};
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import Ember from 'ember';

// An example of how the (hypothetical) service is used in routes.

export default Ember.Route.extend({
  model(params) {
    return this.network.fetch(`/api/posts/${params.post_id}.json`);
  },

  afterModel(post) {
    if (post.isExternalContent) {
      return this.network.fetch(`/api/external/?url=${post.externalURL}`);
    } else {
      return post;
    }
  }
});
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// Finally, put all the pieces together

function discoverResourcesFor(url) {
  return MyApp.visit(url, { isBrowser: false, shouldRender: false }).then(instance => {
    let networkService = instance.lookup('service:network');
    return networkService.requests; // => { "/api/posts/123.json": "..." }
  });
}

Parameters:

url String
The initial URL to navigate to
options Ember.ApplicationInstance.BootOptions

Returns:

Promise

waitForDOMReady

private

Automatically kick-off the boot process for the application once the DOM has become ready.

The initialization itself is scheduled on the actions queue which ensures that code-loading finishes before booting.

If you are asynchronously loading code, you should call deferReadiness() to defer booting, and then call advanceReadiness() once all of your code has finished loading.

willDestroy

public

Override to implement teardown.

Show:

_globalsMode

Boolean private

Whether the application should be configured for the legacy "globals mode". Under this mode, the Application object serves as a global namespace for all classes.

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let App = Ember.Application.create({
  ...
});

App.Router.reopen({
  location: 'none'
});

App.Router.map({
  ...
});

App.MyComponent = Ember.Component.extend({
  ...
});

This flag also exposes other internal APIs that assumes the existence of a special "default instance", like App.__container__.lookup(...).

This option is currently not configurable, its value is derived from the autoboot flag – disabling autoboot also implies opting-out of globals mode support, although they are ultimately orthogonal concerns.

Some of the global modes features are already deprecated in 1.x. The existence of this flag is to untangle the globals mode code paths from the autoboot code paths, so that these legacy features can be reviewed for deprecation/removal separately.

Forcing the (autoboot=true, _globalsMode=false) here and running the tests would reveal all the places where we are still relying on these legacy behavior internally (mostly just tests).

Default: true

_initializersRan

private

A private flag indicating whether an engine's initializers have run yet.

autoboot

Boolean private

Whether the application should automatically start routing and render templates to the rootElement on DOM ready. While default by true, other environments such as FastBoot or a testing harness can set this property to false and control the precise timing and behavior of the boot process.

Default: true

concatenatedProperties

Array public

Defines the properties that will be concatenated from the superclass (instead of overridden).

By default, when you extend an Ember class a property defined in the subclass overrides a property with the same name that is defined in the superclass. However, there are some cases where it is preferable to build up a property's value by combining the superclass' property value with the subclass' value. An example of this in use within Ember is the classNames property of Ember.View.

Here is some sample code showing the difference between a concatenated property and a normal one:

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const Bar = Ember.Object.extend({
  // Configure which properties to concatenate
  concatenatedProperties: ['concatenatedProperty'],

  someNonConcatenatedProperty: ['bar'],
  concatenatedProperty: ['bar']
});

const FooBar = Bar.extend({
  someNonConcatenatedProperty: ['foo'],
  concatenatedProperty: ['foo']
});

let fooBar = FooBar.create();
fooBar.get('someNonConcatenatedProperty'); // ['foo']
fooBar.get('concatenatedProperty'); // ['bar', 'foo']

This behavior extends to object creation as well. Continuing the above example:

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let fooBar = FooBar.create({
  someNonConcatenatedProperty: ['baz'],
  concatenatedProperty: ['baz']
})
fooBar.get('someNonConcatenatedProperty'); // ['baz']
fooBar.get('concatenatedProperty'); // ['bar', 'foo', 'baz']

Adding a single property that is not an array will just add it in the array:

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let fooBar = FooBar.create({
  concatenatedProperty: 'baz'
})
view.get('concatenatedProperty'); // ['bar', 'foo', 'baz']

Using the concatenatedProperties property, we can tell Ember to mix the content of the properties.

In Ember.Component the classNames, classNameBindings and attributeBindings properties are concatenated.

This feature is available for you to use throughout the Ember object model, although typical app developers are likely to use it infrequently. Since it changes expectations about behavior of properties, you should properly document its usage in each individual concatenated property (to not mislead your users to think they can override the property in a subclass).

Default: null

customEvents

Object public

The DOM events for which the event dispatcher should listen.

By default, the application's Ember.EventDispatcher listens for a set of standard DOM events, such as mousedown and keyup, and delegates them to your application's Ember.View instances.

If you would like additional bubbling events to be delegated to your views, set your Ember.Application's customEvents property to a hash containing the DOM event name as the key and the corresponding view method name as the value. Setting an event to a value of null will prevent a default event listener from being added for that event.

To add new events to be listened to:

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let App = Ember.Application.create({
  customEvents: {
    // add support for the paste event
    paste: 'paste'
  }
});

To prevent default events from being listened to:

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let App = Ember.Application.create({
  customEvents: {
    // remove support for mouseenter / mouseleave events
    mouseenter: null,
    mouseleave: null
  }
});

Default: null

eventDispatcher

Ember.EventDispatcher public

The Ember.EventDispatcher responsible for delegating events to this application's views.

The event dispatcher is created by the application at initialization time and sets up event listeners on the DOM element described by the application's rootElement property.

See the documentation for Ember.EventDispatcher for more information.

Default: null

isDestroyed

public

Destroyed object property flag.

if this property is true the observers and bindings were already removed by the effect of calling the destroy() method.

Default: false

isDestroying

public

Destruction scheduled flag. The destroy() method has been called.

The object stays intact until the end of the run loop at which point the isDestroyed flag is set.

Default: false

mergedProperties

Array public

Defines the properties that will be merged from the superclass (instead of overridden).

By default, when you extend an Ember class a property defined in the subclass overrides a property with the same name that is defined in the superclass. However, there are some cases where it is preferable to build up a property's value by merging the superclass property value with the subclass property's value. An example of this in use within Ember is the queryParams property of routes.

Here is some sample code showing the difference between a merged property and a normal one:

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const Bar = Ember.Object.extend({
  // Configure which properties are to be merged
  mergedProperties: ['mergedProperty'],

  someNonMergedProperty: {
    nonMerged: 'superclass value of nonMerged'
  },
  mergedProperty: {
    page: {replace: false},
    limit: {replace: true}
  }
});

const FooBar = Bar.extend({
  someNonMergedProperty: {
    completelyNonMerged: 'subclass value of nonMerged'
  },
  mergedProperty: {
    limit: {replace: false}
  }
});

let fooBar = FooBar.create();

fooBar.get('someNonMergedProperty');
// => { completelyNonMerged: 'subclass value of nonMerged' }
//
// Note the entire object, including the nonMerged property of
// the superclass object, has been replaced

fooBar.get('mergedProperty');
// => {
//   page: {replace: false},
//   limit: {replace: false}
// }
//
// Note the page remains from the superclass, and the
// `limit` property's value of `false` has been merged from
// the subclass.

This behavior is not available during object create calls. It is only available at extend time.

In Ember.Route the queryParams property is merged.

This feature is available for you to use throughout the Ember object model, although typical app developers are likely to use it infrequently. Since it changes expectations about behavior of properties, you should properly document its usage in each individual merged property (to not mislead your users to think they can override the property in a subclass).

Default: null

resolver

public

Set this to provide an alternate class to Ember.DefaultResolver

rootElement

DOMElement public

The root DOM element of the Application. This can be specified as an element or a jQuery-compatible selector string.

This is the element that will be passed to the Application's, eventDispatcher, which sets up the listeners for event delegation. Every view in your application should be a child of the element you specify here.

Default: 'body'

Show:

ready

public

Called when the Application has become ready, immediately before routing begins. The call will be delayed until the DOM has become ready.