Ember.CoreObject Class packages/ember-runtime/lib/system/core_object.js:165


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_scheduledDestroy

private

create

(arguments) 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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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:

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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.

Parameters:

arguments

createWithMixins

(arguments) static

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

Parameters:

arguments

destroy

Ember.Object

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

eachComputedProperty

(callback, binding)

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

extend

(mixins, arguments) static

Creates a new subclass.

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App.Person = Ember.Object.extend({
  say: function(thing) {
    alert(thing);
   }
});

This defines a new subclass of Ember.Object: App.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.View class:

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App.PersonView = Ember.View.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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App.Person = Ember.Object.extend({
  say: function(thing) {
    var name = this.get('name');
    alert(name + ' says: ' + thing);
  }
});

App.Soldier = App.Person.extend({
  say: function(thing) {
    this._super(thing + ", sir!");
  },
  march: function(numberOfHours) {
    alert(this.get('name') + ' marches for ' + numberOfHours + ' hours.')
  }
});

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

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

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

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

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App.Person = Ember.Object.extend({
  say: function(thing) {
    alert(this.get('name') + ' says: ' + thing);
  }
});

App.SingingMixin = Ember.Mixin.create({
  sing: function(thing){
    alert(this.get('name') + ' sings: la la la ' + thing);
  }
});

App.BroadwayStar = App.Person.extend(App.SingingMixin, {
  dance: function() {
    alert(this.get('name') + ' dances: tap tap tap tap ');
  }
});

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

Parameters:

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

init

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

Example:

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App.Person = Ember.Object.extend({
  init: function() {
    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.

metaForProperty

(key)

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: 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:

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MyClass.metaForProperty('person');

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

Parameters:

key String
property name

reopen

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

Augments a constructor's own properties and functions:

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

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

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

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

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

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

toString

String

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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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:

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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.

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

Returns:

String
string representation

willDestroy

Override to implement teardown.

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concatenatedProperties

Array

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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App.BarView = Ember.View.extend({
  someNonConcatenatedProperty: ['bar'],
  classNames: ['bar']
});

App.FooBarView = App.BarView.extend({
  someNonConcatenatedProperty: ['foo'],
  classNames: ['foo'],
});

var fooBarView = App.FooBarView.create();
fooBarView.get('someNonConcatenatedProperty'); // ['foo']
fooBarView.get('classNames'); // ['ember-view', 'bar', 'foo']

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

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var view = App.FooBarView.create({
  someNonConcatenatedProperty: ['baz'],
  classNames: ['baz']
})
view.get('someNonConcatenatedProperty'); // ['baz']
view.get('classNames'); // ['ember-view', 'bar', 'foo', 'baz']

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

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var view = App.FooBarView.create({
  classNames: 'baz'
})
view.get('classNames'); // ['ember-view', 'bar', 'foo', 'baz']

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

In Ember.View the classNameBindings and attributeBindings properties are also concatenated, in addition to classNames.

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

isDestroyed

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

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