Ember.View Class packages/ember-views/lib/views/view.js:6


DEPRECATED

PRIVATE

Extends: Ember.CoreView

Uses: Ember.ViewSupport

Uses: Ember.ChildViewsSupport

Uses: Ember.ClassNamesSupport

Uses: Ember.AttributeBindingsSupport

Defined in: packages/ember-views/lib/views/view.js:6

Module: ember-views

Ember.View is the class in Ember responsible for encapsulating templates of HTML content, combining templates with data to render as sections of a page's DOM, and registering and responding to user-initiated events.

HTML Tag

The default HTML tag name used for a view's DOM representation is div. This can be customized by setting the tagName property. The following view class:

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ParagraphView = Ember.View.extend({
  tagName: 'em'
});

Would result in instances with the following HTML:

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<em id="ember1" class="ember-view"></em>

HTML class Attribute

The HTML class attribute of a view's tag can be set by providing a classNames property that is set to an array of strings:

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MyView = Ember.View.extend({
  classNames: ['my-class', 'my-other-class']
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view my-class my-other-class"></div>

class attribute values can also be set by providing a classNameBindings property set to an array of properties names for the view. The return value of these properties will be added as part of the value for the view's class attribute. These properties can be computed properties:

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MyView = Ember.View.extend({
  classNameBindings: ['propertyA', 'propertyB'],
  propertyA: 'from-a',
  propertyB: Ember.computed(function() {
    if (someLogic) { return 'from-b'; }
  })
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view from-a from-b"></div>

If the value of a class name binding returns a boolean the property name itself will be used as the class name if the property is true. The class name will not be added if the value is false or undefined.

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MyView = Ember.View.extend({
  classNameBindings: ['hovered'],
  hovered: true
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view hovered"></div>

When using boolean class name bindings you can supply a string value other than the property name for use as the class HTML attribute by appending the preferred value after a ":" character when defining the binding:

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MyView = Ember.View.extend({
  classNameBindings: ['awesome:so-very-cool'],
  awesome: true
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view so-very-cool"></div>

Boolean value class name bindings whose property names are in a camelCase-style format will be converted to a dasherized format:

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MyView = Ember.View.extend({
  classNameBindings: ['isUrgent'],
  isUrgent: true
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view is-urgent"></div>

Class name bindings can also refer to object values that are found by traversing a path relative to the view itself:

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MyView = Ember.View.extend({
  classNameBindings: ['messages.empty']
  messages: Ember.Object.create({
    empty: true
  })
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view empty"></div>

If you want to add a class name for a property which evaluates to true and and a different class name if it evaluates to false, you can pass a binding like this:

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// Applies 'enabled' class when isEnabled is true and 'disabled' when isEnabled is false
Ember.View.extend({
  classNameBindings: ['isEnabled:enabled:disabled']
  isEnabled: true
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view enabled"></div>

When isEnabled is false, the resulting HTML representation looks like this:

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<div id="ember1" class="ember-view disabled"></div>

This syntax offers the convenience to add a class if a property is false:

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// Applies no class when isEnabled is true and class 'disabled' when isEnabled is false
Ember.View.extend({
  classNameBindings: ['isEnabled::disabled']
  isEnabled: true
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view"></div>

When the isEnabled property on the view is set to false, it will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view disabled"></div>

Updates to the value of a class name binding will result in automatic update of the HTML class attribute in the view's rendered HTML representation. If the value becomes false or undefined the class name will be removed.

Both classNames and classNameBindings are concatenated properties. See Ember.Object documentation for more information about concatenated properties.

HTML Attributes

The HTML attribute section of a view's tag can be set by providing an attributeBindings property set to an array of property names on the view. The return value of these properties will be used as the value of the view's HTML associated attribute:

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AnchorView = Ember.View.extend({
  tagName: 'a',
  attributeBindings: ['href'],
  href: 'http://google.com'
});

Will result in view instances with an HTML representation of:

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<a id="ember1" class="ember-view" href="http://google.com"></a>

One property can be mapped on to another by placing a ":" between the source property and the destination property:

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AnchorView = Ember.View.extend({
  tagName: 'a',
  attributeBindings: ['url:href'],
  url: 'http://google.com'
});

Will result in view instances with an HTML representation of:

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<a id="ember1" class="ember-view" href="http://google.com"></a>

Namespaced attributes (e.g. xlink:href) are supported, but have to be mapped, since : is not a valid character for properties in Javascript:

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UseView = Ember.View.extend({
  tagName: 'use',
  attributeBindings: ['xlinkHref:xlink:href'],
  xlinkHref: '#triangle'
});

Will result in view instances with an HTML representation of:

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<use xlink:href="#triangle"></use>

If the return value of an attributeBindings monitored property is a boolean the attribute will be present or absent depending on the value:

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MyTextInput = Ember.View.extend({
  tagName: 'input',
  attributeBindings: ['disabled'],
  disabled: false
});

Will result in a view instance with an HTML representation of:

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<input id="ember1" class="ember-view" />

attributeBindings can refer to computed properties:

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MyTextInput = Ember.View.extend({
  tagName: 'input',
  attributeBindings: ['disabled'],
  disabled: Ember.computed(function() {
    if (someLogic) {
      return true;
    } else {
      return false;
    }
  })
});

To prevent setting an attribute altogether, use null or undefined as the return value of the attributeBindings monitored property:

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MyTextInput = Ember.View.extend({
  tagName: 'form',
  attributeBindings: ['novalidate'],
  novalidate: null
});

Updates to the property of an attribute binding will result in automatic update of the HTML attribute in the view's rendered HTML representation.

attributeBindings is a concatenated property. See Ember.Object documentation for more information about concatenated properties.

Layouts

Views can have a secondary template that wraps their main template. Like primary templates, layouts can be any function that accepts an optional context parameter and returns a string of HTML that will be inserted inside view's tag. Views whose HTML element is self closing (e.g. <input />) cannot have a layout and this property will be ignored.

Most typically in Ember a layout will be a compiled template.

A view's layout can be set directly with the layout property or reference an existing template by name with the layoutName property.

A template used as a layout must contain a single use of the {{yield}} helper. The HTML contents of a view's rendered template will be inserted at this location:

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AViewWithLayout = Ember.View.extend({
  layout: Ember.HTMLBars.compile("<div class='my-decorative-class'>{{yield}}</div>"),
  template: Ember.HTMLBars.compile("I got wrapped")
});

Will result in view instances with an HTML representation of:

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<div id="ember1" class="ember-view">
  <div class="my-decorative-class">
    I got wrapped
  </div>
</div>

See Ember.Templates.helpers.yield for more information.

Responding to Browser Events

Views can respond to user-initiated events in one of three ways: method implementation, through an event manager, and through {{action}} helper use in their template or layout.

Method Implementation

Views can respond to user-initiated events by implementing a method that matches the event name. A jQuery.Event object will be passed as the argument to this method.

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AView = Ember.View.extend({
  click: function(event) {
    // will be called when an instance's
    // rendered element is clicked
  }
});

Event Managers

Views can define an object as their eventManager property. This object can then implement methods that match the desired event names. Matching events that occur on the view's rendered HTML or the rendered HTML of any of its DOM descendants will trigger this method. A jQuery.Event object will be passed as the first argument to the method and an Ember.View object as the second. The Ember.View will be the view whose rendered HTML was interacted with. This may be the view with the eventManager property or one of its descendant views.

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AView = Ember.View.extend({
  eventManager: Ember.Object.create({
    doubleClick: function(event, view) {
      // will be called when an instance's
      // rendered element or any rendering
      // of this view's descendant
      // elements is clicked
    }
  })
});

An event defined for an event manager takes precedence over events of the same name handled through methods on the view.

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AView = Ember.View.extend({
  mouseEnter: function(event) {
    // will never trigger.
  },
  eventManager: Ember.Object.create({
    mouseEnter: function(event, view) {
      // takes precedence over AView#mouseEnter
    }
  })
});

Similarly a view's event manager will take precedence for events of any views rendered as a descendant. A method name that matches an event name will not be called if the view instance was rendered inside the HTML representation of a view that has an eventManager property defined that handles events of the name. Events not handled by the event manager will still trigger method calls on the descendant.

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var App = Ember.Application.create();
App.OuterView = Ember.View.extend({
  template: Ember.HTMLBars.compile("outer {{#view 'inner'}}inner{{/view}} outer"),
  eventManager: Ember.Object.create({
    mouseEnter: function(event, view) {
      // view might be instance of either
      // OuterView or InnerView depending on
      // where on the page the user interaction occurred
    }
  })
});

App.InnerView = Ember.View.extend({
  click: function(event) {
    // will be called if rendered inside
    // an OuterView because OuterView's
    // eventManager doesn't handle click events
  },
  mouseEnter: function(event) {
    // will never be called if rendered inside
    // an OuterView.
  }
});

{{action}} Helper

See Ember.Templates.helpers.action.

Event Names

All of the event handling approaches described above respond to the same set of events. The names of the built-in events are listed below. (The hash of built-in events exists in Ember.EventDispatcher.) Additional, custom events can be registered by using Ember.Application.customEvents.

Touch events:

  • touchStart
  • touchMove
  • touchEnd
  • touchCancel

Keyboard events

  • keyDown
  • keyUp
  • keyPress

Mouse events

  • mouseDown
  • mouseUp
  • contextMenu
  • click
  • doubleClick
  • mouseMove
  • focusIn
  • focusOut
  • mouseEnter
  • mouseLeave

Form events:

  • submit
  • change
  • focusIn
  • focusOut
  • input

HTML5 drag and drop events:

  • dragStart
  • drag
  • dragEnter
  • dragLeave
  • dragOver
  • dragEnd
  • drop
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.

_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.

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

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

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

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

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.

getChildViews

(view) private

Parameters:

view Ember.View

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

getRootViews

(owner) private

Parameters:

owner Object

getViewBoundingClientRect

(view) private

getViewBoundingClientRect provides information about the position of the bounding border box edges of a view relative to the viewport.

It is only intended to be used by development tools like the Ember Inpsector and may not work on older browsers.

Parameters:

view Ember.View

getViewBounds

(view) private

Parameters:

view Ember.View

getViewClientRects

(view) private

getViewClientRects provides information about the position of the border box edges of a view relative to the viewport.

It is only intended to be used by development tools like the Ember Inspector and may not work on older browsers.

Parameters:

view Ember.View

getViewElement

(view) private

Parameters:

view Ember.View

getViewId

(view) private

Parameters:

view Ember.View

getViewRange

(view) private

Parameters:

view Ember.View

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.

has

(name) Boolean public

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

Parameters:

name String
The name of the event

Returns:

Boolean
does the object have a subscription for event

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

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.

matches

(el, selector) private

Determines if the element matches the specified selector.

Parameters:

el DOMElement
selector String

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

off

(name, target, method) public

Cancels subscription for given name, target, and method.

Parameters:

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

Returns:

this

on

(name, target, method) public

Subscribes to a named event with given function.

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

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

Parameters:

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

Returns:

this

one

(name, target, method) public

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

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

Parameters:

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

Returns:

this

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

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

send

(actionName, context) public

Triggers a named action on the ActionHandler. Any parameters supplied after the actionName string will be passed as arguments to the action target function.

If the ActionHandler has its target property set, actions may bubble to the target. Bubbling happens when an actionName can not be found in the ActionHandler's actions hash or if the action target function returns true.

Example

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App.WelcomeRoute = Ember.Route.extend({
  actions: {
    playTheme() {
       this.send('playMusic', 'theme.mp3');
    },
    playMusic(track) {
      // ...
    }
  }
});

Parameters:

actionName String
The action to trigger
context *
a context to send with the action

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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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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starship.toggleProperty('warpDriveEngaged');

Parameters:

keyName String
The name of the property to toggle

Returns:

Boolean
The new property value

trigger

(name) private

Override the default event firing from Ember.Evented to also call methods with the given name.

Parameters:

name String

willDestroy

public

Override to implement teardown.

Show:

actions

Object public

The collection of functions, keyed by name, available on this ActionHandler as action targets.

These functions will be invoked when a matching {{action}} is triggered from within a template and the application's current route is this route.

Actions can also be invoked from other parts of your application via ActionHandler#send.

The actions hash will inherit action handlers from the actions hash defined on extended parent classes or mixins rather than just replace the entire hash, e.g.:

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App.CanDisplayBanner = Ember.Mixin.create({
  actions: {
    displayBanner(msg) {
      // ...
    }
  }
});

App.WelcomeRoute = Ember.Route.extend(App.CanDisplayBanner, {
  actions: {
    playMusic() {
      // ...
    }
  }
});

// `WelcomeRoute`, when active, will be able to respond
// to both actions, since the actions hash is merged rather
// then replaced when extending mixins / parent classes.
this.send('displayBanner');
this.send('playMusic');

Within a Controller, Route or Component's action handler, the value of the this context is the Controller, Route or Component object:

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App.SongRoute = Ember.Route.extend({
  actions: {
    myAction() {
      this.controllerFor("song");
      this.transitionTo("other.route");
      ...
    }
  }
});

It is also possible to call this._super(...arguments) from within an action handler if it overrides a handler defined on a parent class or mixin:

Take for example the following routes:

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App.DebugRoute = Ember.Mixin.create({
  actions: {
    debugRouteInformation() {
      console.debug("trololo");
    }
  }
});

App.AnnoyingDebugRoute = Ember.Route.extend(App.DebugRoute, {
  actions: {
    debugRouteInformation() {
      // also call the debugRouteInformation of mixed in App.DebugRoute
      this._super(...arguments);

      // show additional annoyance
      window.alert(...);
    }
  }
});

Bubbling

By default, an action will stop bubbling once a handler defined on the actions hash handles it. To continue bubbling the action, you must return true from the handler:

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App.Router.map(function() {
  this.route("album", function() {
    this.route("song");
  });
});

App.AlbumRoute = Ember.Route.extend({
  actions: {
    startPlaying: function() {
    }
  }
});

App.AlbumSongRoute = Ember.Route.extend({
  actions: {
    startPlaying() {
      // ...

      if (actionShouldAlsoBeTriggeredOnParentRoute) {
        return true;
      }
    }
  }
});

Default: null

childViews

Array private

Array of child views. You should never edit this array directly.

Default: []

classNameBindings

Array public

A list of properties of the view to apply as class names. If the property is a string value, the value of that string will be applied as a class name.

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// Applies the 'high' class to the view element
Ember.Component.extend({
  classNameBindings: ['priority'],
  priority: 'high'
});

If the value of the property is a Boolean, the name of that property is added as a dasherized class name.

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// Applies the 'is-urgent' class to the view element
Ember.Component.extend({
  classNameBindings: ['isUrgent'],
  isUrgent: true
});

If you would prefer to use a custom value instead of the dasherized property name, you can pass a binding like this:

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// Applies the 'urgent' class to the view element
Ember.Component.extend({
  classNameBindings: ['isUrgent:urgent'],
  isUrgent: true
});

This list of properties is inherited from the component's superclasses as well.

Default: []

classNames

Array public

Standard CSS class names to apply to the view's outer element. This property automatically inherits any class names defined by the view's superclasses as well.

Default: ['ember-view']

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

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

parentView

Ember.View private

If the view is currently inserted into the DOM of a parent view, this property will point to the parent of the view.

Default: null