Class Ember.TextArea
publicThe internal class used to create textarea element when the {{textarea}}
helper is used.
See Ember.Templates.helpers.textarea for usage details.
Layout and LayoutName properties
Because HTML textarea
elements do not contain inner HTML the layout
and
layoutName
properties will not be applied. See Ember.View's
layout section for more information.
$ (selector) JQuery public
Inherited from Ember.ViewTargetActionSupport packages/ember-views/lib/mixins/view_support.js:205
- selector
- String
- a jQuery-compatible selector string
- returns
- JQuery
- the jQuery object for the DOM node
Returns a jQuery object for this view's element. If you pass in a selector string, this method will return a jQuery object, using the current element as its buffer.
For example, calling view.$('li')
will return a jQuery object containing
all of the li
elements inside the DOM element of this view.
addObserver (key, target, method) public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:333
- key
- String
- The key to observer
- target
- Object
- The target object to invoke
- method
- String|Function
- The method to invoke.
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:
1 |
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.
cacheFor (keyName) Object public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:490
- keyName
- String
- returns
- Object
- The cached value of the computed property, if any
Returns the cached value of a computed property, if it exists. This allows you to inspect the value of a computed property without accidentally invoking it if it is intended to be generated lazily.
create (arguments) public
Inherited from Ember.Mixin packages/ember-metal/lib/mixin.js:524
- arguments
create (arguments) public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:657
- arguments
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
.
decrementProperty (keyName, decrement) Number public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:453
- keyName
- String
- The name of the property to decrement
- decrement
- Number
- The amount to decrement by. Defaults to 1
- returns
- Number
- The new property value
Set the value of a property to the current value minus some amount.
1 2 |
player.decrementProperty('lives'); orc.decrementProperty('health', 5); |
destroy Ember.Object public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:434
- returns
- Ember.Object
- receiver
Destroys an object by setting the isDestroyed
flag and removing its
metadata, which effectively destroys observers and bindings.
If you try to set a property on a destroyed object, an exception will be raised.
Note that destruction is scheduled for the end of the run loop and does not happen immediately. It will set an isDestroying flag immediately.
didReceiveAttrs public
Inherited from Ember.Component packages/ember-views/lib/components/component.js:483
Available since v1.13.0
Called when the attributes passed into the component have been updated. Called both during the initial render of a container and during a rerender. Can be used in place of an observer; code placed here will be executed every time any attribute updates.
didRender public
Inherited from Ember.Component packages/ember-views/lib/components/component.js:505
Available since v1.13.0
Called after a component has been rendered, both on initial render and in subsequent rerenders.
didUpdateAttrs public
Inherited from Ember.Component packages/ember-views/lib/components/component.js:541
Available since v1.13.0
Called when the attributes passed into the component have been changed. Called only during a rerender, not during an initial render.
extend (mixins, arguments) public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:549
- mixins
- Mixin
- One or more Mixin classes
- arguments
- Object
- Object containing values to use within the new class
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 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 = 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()
.
get (keyName) Object public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:100
- keyName
- String
- The property to retrieve
- returns
- Object
- The property value or undefined.
Retrieves the value of a property from the object.
This method is usually similar to using object[keyName]
or object.keyName
,
however it supports both computed properties and the unknownProperty
handler.
Because get
unifies the syntax for accessing all these kinds
of properties, it can make many refactorings easier, such as replacing a
simple property with a computed property, or vice versa.
Computed Properties
Computed properties are methods defined with the property
modifier
declared at the end, such as:
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fullName: function() { return this.get('firstName') + ' ' + this.get('lastName'); }.property('firstName', 'lastName') |
When you call get
on a computed property, the function will be
called and the return value will be returned instead of the function
itself.
Unknown Properties
Likewise, if you try to call get
on a property whose value is
undefined
, the unknownProperty()
method will be called on the object.
If this method returns any value other than undefined
, it will be returned
instead. This allows you to implement "virtual" properties that are
not defined upfront.
getProperties (list) Object public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:143
- list
- String...|Array
- of keys to get
- returns
- Object
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:
1 2 |
record.getProperties(['firstName', 'lastName', 'zipCode']); // { firstName: 'John', lastName: 'Doe', zipCode: '10011' } |
getWithDefault (keyName, defaultValue) Object public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:415
- keyName
- String
- The name of the property to retrieve
- defaultValue
- Object
- The value to return if the property value is undefined
- returns
- Object
- The property value or the defaultValue.
Retrieves the value of a property, or a default value in the case that the
property returns undefined
.
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person.getWithDefault('lastName', 'Doe'); |
has (name) Boolean public
Inherited from Ember.Evented packages/ember-runtime/lib/mixins/evented.js:142
- name
- String
- The name of the event
- returns
- Boolean
- does the object have a subscription for event
Checks to see if object has any subscriptions for named event.
incrementProperty (keyName, increment) Number public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:433
- keyName
- String
- The name of the property to increment
- increment
- Number
- The amount to increment by. Defaults to 1
- returns
- Number
- The new property value
Set the value of a property to the current value plus some amount.
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person.incrementProperty('age'); team.incrementProperty('score', 2); |
init public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:234
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
,
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.
notifyPropertyChange (keyName) Ember.Observable public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:318
- keyName
- String
- The property key to be notified about.
- returns
- Ember.Observable
Convenience method to call propertyWillChange
and propertyDidChange
in
succession.
off (name, target, method) public
Inherited from Ember.Evented packages/ember-runtime/lib/mixins/evented.js:127
- name
- String
- The name of the event
- target
- Object
- The target of the subscription
- method
- Function
- The function of the subscription
- returns
- this
Cancels subscription for given name, target, and method.
on (name, target, method) public
Inherited from Ember.Evented packages/ember-runtime/lib/mixins/evented.js:52
- name
- String
- The name of the event
- target
- Object
- The "this" binding for the callback
- method
- Function
- The callback to execute
- returns
- this
Subscribes to a named event with given function.
1 2 3 |
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.
one (name, target, method) public
Inherited from Ember.Evented packages/ember-runtime/lib/mixins/evented.js:78
- name
- String
- The name of the event
- target
- Object
- The "this" binding for the callback
- method
- Function
- The callback to execute
- returns
- this
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.
readDOMAttr (name) public
Inherited from Ember.ViewTargetActionSupport packages/ember-views/lib/mixins/view_support.js:580
- name
- String
- the name of the attribute
- returns
- String
Normally, Ember's component model is "write-only". The component takes a bunch of attributes that it got passed in, and uses them to render its template.
One nice thing about this model is that if you try to set a value to the same thing as last time, Ember (through HTMLBars) will avoid doing any work on the DOM.
This is not just a performance optimization. If an attribute has not
changed, it is important not to clobber the element's "hidden state".
For example, if you set an input's value
to the same value as before,
it will clobber selection state and cursor position. In other words,
setting an attribute is not always idempotent.
This method provides a way to read an element's attribute and also update the last value Ember knows about at the same time. This makes setting an attribute idempotent.
In particular, what this means is that if you get an <input>
element's
value
attribute and then re-render the template with the same value,
it will avoid clobbering the cursor and selection position.
Since most attribute sets are idempotent in the browser, you typically can get away with reading attributes using jQuery, but the most reliable way to do so is through this method.
removeObserver (key, target, method) public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:385
- key
- String
- The key to observer
- target
- Object
- The target object to invoke
- method
- String|Function
- The method to invoke.
Remove an observer you have previously registered on this object. Pass
the same key, target, and method you passed to addObserver()
and your
target will no longer receive notifications.
reopen public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:703
Augments a constructor's prototype with additional properties and functions:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 |
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 public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:739
Augments a constructor's own properties and functions:
1 2 3 4 5 6 7 8 9 10 |
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.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 |
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
rerender public
Inherited from Ember.ViewTargetActionSupport packages/ember-views/lib/mixins/view_support.js:171
Renders the view again. This will work regardless of whether the view is already in the DOM or not. If the view is in the DOM, the rendering process will be deferred to give bindings a chance to synchronize.
If children were added during the rendering process using appendChild
,
rerender
will remove them, because they will be added again
if needed by the next render
.
In general, if the display of your view changes, you should modify
the DOM element directly instead of manually calling rerender
, which can
be slow.
send (actionName, context) public
Inherited from Ember.ActionHandler packages/ember-runtime/lib/mixins/action_handler.js:145
- actionName
- String
- The action to trigger
- context
- *
- a context to send with the action
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: function() { this.send('playMusic', 'theme.mp3'); }, playMusic: function(track) { // ... } } }); |
sendAction (action, params) public
Inherited from Ember.Component packages/ember-views/lib/components/component.js:203
- action
- String
- the action to call
- params
- *
- arguments for the action
Calls a action passed to a component.
For example a component for playing or pausing music may translate click events into action notifications of "play" or "stop" depending on some internal state of the component:
1 2 3 4 5 6 7 8 9 10 |
// app/components/play-button.js export default Ember.Component.extend({ click() { if (this.get('isPlaying')) { this.sendAction('play'); } else { this.sendAction('stop'); } } }); |
The actions "play" and "stop" must be passed to this play-button
component:
When the component receives a browser click
event it translate this
interaction into application-specific semantics ("play" or "stop") and
calls the specified action.
1 2 3 4 5 6 7 8 9 10 11 12 13 |
// app/controller/application.js export default Ember.Controller.extend({ actions: { musicStarted() { // called when the play button is clicked // and the music started playing }, musicStopped() { // called when the play button is clicked // and the music stopped playing } } }); |
If no action is passed to sendAction
a default name of "action"
is assumed.
1 2 3 4 5 6 |
// app/components/next-button.js export default Ember.Component.extend({ click() { this.sendAction(); } }); |
1 2 3 4 5 6 7 8 |
// app/controllers/application.js App.ApplicationController = Ember.Controller.extend({ actions: { playNextSongInAlbum() { ... } } }); |
set (keyName, value) Object public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:168
- keyName
- String
- The property to set
- value
- Object
- The value to set or `null`.
- returns
- Object
- The passed value
Sets the provided key or path to the value.
This method is generally very similar to calling object[key] = value
or
object.key = value
, except that it provides support for computed
properties, the setUnknownProperty()
method and property observers.
Computed Properties
If you try to set a value on a key that has a computed property handler
defined (see the get()
method for an example), then set()
will call
that method, passing both the value and key instead of simply changing
the value itself. This is useful for those times when you need to
implement a property that is composed of one or more member
properties.
Unknown Properties
If you try to set a value on a key that is undefined in the target
object, then the setUnknownProperty()
handler will be called instead. This
gives you an opportunity to implement complex "virtual" properties that
are not predefined on the object. If setUnknownProperty()
returns
undefined, then set()
will simply set the value on the object.
Property Observers
In addition to changing the property, set()
will also register a property
change with the object. Unless you have placed this call inside of a
beginPropertyChanges()
and endPropertyChanges(),
any "local" observers
(i.e. observer methods declared on the same object), will be called
immediately. Any "remote" observers (i.e. observer methods declared on
another object) will be placed in a queue and called at a later time in a
coalesced manner.
setProperties (hash) Object public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:213
- hash
- Object
- the hash of keys and values to set
- returns
- Object
- The passed in hash
Sets a list of properties at once. These properties are set inside
a single beginPropertyChanges
and endPropertyChanges
batch, so
observers will be buffered.
1 |
record.setProperties({ firstName: 'Charles', lastName: 'Jolley' }); |
toString String public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:484
- returns
- String
- string representation
Returns a string representation which attempts to provide more information
than Javascript's toString
typically does, in a generic way for all Ember
objects.
1 2 3 |
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:
1 2 3 |
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.
1 2 3 4 5 6 7 |
App.Teacher = App.Person.extend({ toStringExtension: function() { return this.get('fullName'); } }); teacher = App.Teacher.create() teacher.toString(); //=> "<App.Teacher:ember1026:Tom Dale>" |
toggleProperty (keyName) Boolean public
Inherited from Ember.Observable packages/ember-runtime/lib/mixins/observable.js:473
- keyName
- String
- The name of the property to toggle
- returns
- Boolean
- The new property value
Set the value of a boolean property to the opposite of its current value.
1 |
starship.toggleProperty('warpDriveEngaged'); |
trigger (name, args) public
Inherited from Ember.Evented packages/ember-runtime/lib/mixins/evented.js:104
- name
- String
- The name of the event
- args
- Object...
- Optional arguments to pass on
Triggers a named event for the object. Any additional arguments will be passed as parameters to the functions that are subscribed to the event.
1 2 3 4 5 6 7 |
person.on('didEat', function(food) { console.log('person ate some ' + food); }); person.trigger('didEat', 'broccoli'); // outputs: person ate some broccoli |
willDestroy public
Inherited from Ember.CoreObject packages/ember-runtime/lib/system/core_object.js:457
Override to implement teardown.
willRender public
Inherited from Ember.Component packages/ember-views/lib/components/component.js:523
Available since v1.13.0
Called before a component has been rendered, both on initial render and in subsequent rerenders.
willUpdate public
Inherited from Ember.Component packages/ember-views/lib/components/component.js:559
Available since v1.13.0
Called when the component is about to update and rerender itself. Called only during a rerender, not during an initial render.