Ember.TextArea Class packages/ember-handlebars/lib/controls/text_area.js:12

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.

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.

Appends the view's element to the document body. If the view does not have an HTML representation yet, createElement() will be called automatically.

If your application uses the rootElement property, you must append the view within that element. Rendering views outside of the rootElement is not supported.

Note that this method just schedules the view to be appended; the DOM element will not be appended to the document body until all bindings have finished synchronizing.

Appends the view's element to the specified parent element.

If the view does not have an HTML representation yet, createElement() will be called automatically.

Note that this method just schedules the view to be appended; the DOM element will not be appended to the given element until all bindings have finished synchronizing.

This is not typically a function that you will need to call directly when building your application. You might consider using Ember.ContainerView instead. If you do need to use appendTo, be sure that the target element you are providing is associated with an Ember.Application and does not have an ancestor element that is associated with an Ember view.

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 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.

Called when the user hits escape.

Called by the Ember.TextSupport mixin on keyUp if keycode matches 27. Uses sendAction to send the escape-press action to the controller.

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.

Instantiates a view to be added to the childViews array during view initialization. You generally will not call this method directly unless you are overriding createChildViews(). Note that this method will automatically configure the correct settings on the new view instance to act as a child of the parent.

Creates a DOM representation of the view and all of its child views by recursively calling the render() method.

After the element has been created, didInsertElement will be called on this view and all of its child views.

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

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

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

You must call destroy on a view to destroy the view (and all of its child views). This will remove the view from any parent node, then make sure that the DOM element managed by the view can be released by the memory manager.

Destroys any existing element along with the element for any child views as well. If the view does not currently have a element, then this method will do nothing.

If you implement willDestroyElement() on your view, then this method will be invoked on your view before your element is destroyed to give you a chance to clean up any event handlers, etc.

If you write a willDestroyElement() handler, you can assume that your didInsertElement() handler was called earlier for the same element.

You should not call or override this method yourself, but you may want to implement the above callbacks.

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

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.

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().

Attempts to discover the element in the parent element. The default implementation looks for an element with an ID of elementId (or the view's guid if elementId is null). You can override this method to provide your own form of lookup. For example, if you want to discover your element using a CSS class name instead of an ID.

Called when the text area is focused.

Called when the text area is blurred.

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.

To get 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' }

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');

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

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.

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

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

The action to be sent when the user inserts a new line.

Called by the Ember.TextSupport mixin on keyUp if keycode matches 13. Uses sendAction to send the enter action to the controller.

The action to be sent when the user presses a key. Enabled by setting the onEvent property to keyPress.

Uses sendAction to send the keyPress action to the controller.

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().

Convenience method to call propertyWillChange and propertyDidChange in succession.

Cancels subscription for given name, target, and method.

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.

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.

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.

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.

Removes the view's element from the element to which it is attached.

Removes all children from the parentView.

Removes the child view from the parent view.

Removes the view from its parentView, if one is found. Otherwise does nothing.

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.

Called on your view when it should push strings of HTML into a Ember.RenderBuffer. Most users will want to override the template or templateName properties instead of this method.

By default, Ember.View will look for a function in the template property and invoke it with the value of context. The value of context will be the view's controller unless you override it.

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

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

Replaces the content of the specified parent element with this view's element. If the view does not have an HTML representation yet, createElement() will be called automatically.

Note that this method just schedules the view to be appended; the DOM element will not be appended to the given element until all bindings have finished synchronizing

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.

Triggers a named action on the controller context where the component is used if this controller has registered for notifications of the action.

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:

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App.PlayButtonComponent = Ember.Component.extend({
  click: function(){
    if (this.get('isPlaying')) {
      this.triggerAction('play');
    } else {
      this.triggerAction('stop');
    }
  }
});

When used inside a template these component actions are configured to trigger actions in the outer application context:

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{{! application.hbs }}
{{play-button play="musicStarted" stop="musicStopped"}}

When the component receives a browser click event it translate this interaction into application-specific semantics ("play" or "stop") and triggers the specified action name on the controller for the template where the component is used:

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App.ApplicationController = Ember.Controller.extend({
  actions: {
    musicStarted: function(){
      // called when the play button is clicked
      // and the music started playing
    },
    musicStopped: function(){
      // called when the play button is clicked
      // and the music stopped playing
    }
  }
});

If no action name is passed to sendAction a default name of "action" is assumed.

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App.NextButtonComponent = Ember.Component.extend({
  click: function(){
    this.sendAction();
  }
});

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{{! application.hbs }}
{{next-button action="playNextSongInAlbum"}}

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App.ApplicationController = Ember.Controller.extend({
  actions: {
    playNextSongInAlbum: function(){
      ...
    }
  }
});

Sets the provided key or path to the value.

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

Computed Properties

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

Unknown Properties

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

Property Observers

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

Chaining

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

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

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

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

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>"

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

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starship.toggleProperty('warpDriveEngaged');

Override to implement teardown.