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Summary
Item Index
Methods
- $
- _classStringForProperty
- _contextDidChange
- _isVisibleDidChange
- _lazyInjections
- _onLookup
- _register
- _scheduledDestroy
- _unregister
- addObserver
- append
- appendTo
- beginPropertyChanges
- cacheFor
- createChildView
- createElement
- decrementProperty
- destroy
- destroyElement
- didReceiveAttrs
- didRender
- didUpdateAttrs
- endPropertyChanges
- findElementInParentElement
- get
- getProperties
- getWithDefault
- handleEvent
- has
- hasObserverFor
- incrementProperty
- init
- nearestChildOf deprecated
- nearestInstanceOf deprecated
- nearestOfType
- nearestWithProperty
- notifyPropertyChange
- off
- on
- one
- propertyDidChange
- propertyWillChange
- readDOMAttr
- remove
- removeAllChildren
- removeChild
- removeFromParent
- removeObserver
- renderBlock
- renderToElement
- reopen
- reopenClass
- replaceIn
- rerender
- send
- sendAction
- set
- setProperties
- toggleProperty
- toString
- trigger
- willDestroy
- willRender
- willUpdate
Properties
- _context
- actionContext
- actions
- ariaRole
- childViews
- classNameBindings
- classNames
- concatenatedProperties
- context
- controller
- element
- elementId
- hasBlock
- hasBlockParams
- instrumentDisplay
- isDestroyed
- isDestroying
- isVisible
- layout
- layoutName
- mergedProperties
- parentView
- tagName
- target
- targetObject
- template
- templateName
Methods
$
Syntax
$
(
JQuery
public
-
[selector]
Summary
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, callingview.$('li') will return a jQuery object containing
all of the li elements inside the DOM element of this view.
Parameters:
-
[selector]String optionala jQuery-compatible selector string
Returns:
JQuery:
the jQuery object for the DOM node
_classStringForProperty
Syntax
_classStringForProperty
(
private
-
property
Summary
Given a property name, returns a dasherized version of that property name if the property evaluates to a non-falsy value. For example, if the view has propertyisUrgent that evaluates to true,
passing isUrgent to this method will return "is-urgent".
Parameters:
-
propertyObject
_contextDidChange
Syntax
_contextDidChange
()
private
Summary
If a value that affects template rendering changes, the view should be re-rendered to reflect the new value._isVisibleDidChange
Syntax
_isVisibleDidChange
()
private
Summary
When the view'sisVisible property changes, toggle the visibility
element of the actual DOM element.
_lazyInjections
Syntax
Summary
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
Syntax
_onLookup
()
private
Summary
Provides lookup-time type validation for injected properties._register
Syntax
_register
()
private
Summary
Registers the view in the view registry, keyed on the view'selementId.
This is used by the EventDispatcher to locate the view in response to
events.
This method should only be called once the view has been inserted into the
DOM.
_scheduledDestroy
Syntax
_scheduledDestroy
()
private
Summary
Invoked by the run loop to actually destroy the object. This is scheduled for execution by thedestroy method.
_unregister
Syntax
_unregister
()
private
Summary
Removes the view from the view registry. This should be called when the view is removed from DOM.addObserver
Syntax
addObserver
(
public
-
key -
target -
method
Summary
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 acontext parameter:
`javascript
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:
`javascript
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.
append
Syntax
Summary
Appends the view's element to the document body. If the view does not have an HTML representation yet the element will be generated automatically. If your application uses therootElement 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.
Returns:
Ember.View:
receiver
appendTo
Syntax
Summary
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. 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.
Parameters:
-
AString | DOMElement | JQueryselector, element, HTML string, or jQuery object
Returns:
Ember.View:
receiver
beginPropertyChanges
Syntax
Summary
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, callendPropertyChanges() to deliver the deferred change notifications and end
deferring.
Returns:
cacheFor
Syntax
Summary
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:
-
keyNameString
Returns:
Object:
The cached value of the computed property, if any
createChildView
Syntax
Summary
Instantiates a view to be added to the childViews array during view initialization. You generally will not call this method directly unless you are overridingcreateChildViews(). Note that this method will
automatically configure the correct settings on the new view instance to
act as a child of the parent.
Returns:
Ember.View:
new instance
createElement
Syntax
Summary
Creates a DOM representation of the view and all of its child views by recursively calling therender() method. Once the element is created,
it sets the element property of the view to the rendered element.
After the element has been inserted into the DOM, didInsertElement will
be called on this view and all of its child views.
Returns:
Ember.View:
receiver
decrementProperty
Syntax
Summary
Set the value of a property to the current value minus some amount.`javascript
player.decrementProperty('lives');
orc.decrementProperty('health', 5);
`
Parameters:
Returns:
Number:
The new property value
destroy
Syntax
destroy
()
private
Summary
You must calldestroy 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.
destroyElement
Syntax
Summary
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 implementwillDestroyElement() 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.
Returns:
Ember.View:
receiver
didReceiveAttrs
Syntax
didReceiveAttrs
()
public
Summary
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
Syntax
didRender
()
public
Summary
Called after a component has been rendered, both on initial render and in subsequent rerenders.didUpdateAttrs
Syntax
didUpdateAttrs
()
public
Summary
Called when the attributes passed into the component have been changed. Called only during a rerender, not during an initial render.endPropertyChanges
Syntax
Summary
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 callbeginPropertyChanges() 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:
findElementInParentElement
Syntax
findElementInParentElement
(
DOMElement
private
-
parentElement
Summary
Attempts to discover the element in the parent element. The default implementation looks for an element with an ID ofelementId (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.
Parameters:
-
parentElementDOMElementThe parent's DOM element
Returns:
DOMElement:
The discovered element
get
Syntax
Summary
Retrieves the value of a property from the object. This method is usually similar to usingobject[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:
`javascript
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.
Parameters:
-
keyNameStringThe property to retrieve
Returns:
Object:
The property value or undefined.
getProperties
Syntax
Summary
To get the values of multiple properties at once, callgetProperties
with a list of strings or an array:
`javascript
record.getProperties('firstName', 'lastName', 'zipCode');
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }
`
is equivalent to:
`javascript
record.getProperties(['firstName', 'lastName', 'zipCode']);
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }
`
Parameters:
-
listString... | Arrayof keys to get
Returns:
getWithDefault
Syntax
Summary
Retrieves the value of a property, or a default value in the case that the property returnsundefined.
`javascript
person.getWithDefault('lastName', 'Doe');
`
Parameters:
Returns:
Object:
The property value or the defaultValue.
handleEvent
Syntax
handleEvent
(
private
-
eventName -
evt
Summary
Handle events fromEmber.EventDispatcher
has
Syntax
Summary
Checks to see if object has any subscriptions for named event.Parameters:
-
nameStringThe name of the event
Returns:
Boolean:
does the object have a subscription for event
hasObserverFor
Syntax
Summary
Returnstrue 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:
-
keyStringKey to check
Returns:
incrementProperty
Syntax
Summary
Set the value of a property to the current value plus some amount.`javascript
person.incrementProperty('age');
team.incrementProperty('score', 2);
`
Parameters:
Returns:
Number:
The new property value
init
Syntax
init
()
private
Summary
Setup a view, but do not finish waking it up. * configurechildViews
* register the view with the global views hash, which is used for event
dispatch
nearestChildOf
Syntax
nearestChildOf
(
deprecated
private
-
klass
Summary
Return the nearest ancestor whose parent is an instance ofklass.
Parameters:
-
klassClassSubclass of Ember.View (or Ember.View itself)
Returns:
Ember.View
nearestInstanceOf
Syntax
nearestInstanceOf
(
deprecated
private
-
klass
Summary
Return the nearest ancestor that is an instance of the provided class.Parameters:
-
klassClassSubclass of Ember.View (or Ember.View itself)
Returns:
Ember.View
nearestOfType
Syntax
nearestOfType
(
private
-
klass
Summary
Return the nearest ancestor that is an instance of the provided class or mixin.Parameters:
-
klassClass,MixinSubclass of Ember.View (or Ember.View itself), or an instance of Ember.Mixin.
Returns:
Ember.View
nearestWithProperty
Syntax
nearestWithProperty
(
private
-
property
Summary
Return the nearest ancestor that has a given property.Parameters:
-
propertyStringA property name
Returns:
Ember.View
notifyPropertyChange
Syntax
Summary
Convenience method to callpropertyWillChange and propertyDidChange in
succession.
Parameters:
-
keyNameStringThe property key to be notified about.
Returns:
off
Syntax
off
(
public
-
name -
target -
method
Summary
Cancels subscription for given name, target, and method.Parameters:
Returns:
this
on
Syntax
on
(
public
-
name -
[target] -
method
Summary
Subscribes to a named event with given function.`javascript
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:
Returns:
this
one
Syntax
one
(
public
-
name -
[target] -
method
Summary
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:
Returns:
this
propertyDidChange
Syntax
Summary
Notify the observer system that a property has just changed. Sometimes you need to change a value directly or indirectly without actually callingget() 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:
-
keyNameStringThe property key that has just changed.
Returns:
propertyWillChange
Syntax
Summary
Notify the observer system that a property is about to change. Sometimes you need to change a value directly or indirectly without actually callingget() 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:
-
keyNameStringThe property key that is about to change.
Returns:
readDOMAttr
Syntax
readDOMAttr
(
public
-
name
Summary
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'svalue 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.
Parameters:
-
nameStringthe name of the attribute
Returns:
String
remove
Syntax
Summary
Removes the view's element from the element to which it is attached.Returns:
Ember.View:
receiver
removeAllChildren
Syntax
Summary
Removes all children from theparentView.
Returns:
Ember.View:
receiver
removeChild
Syntax
Summary
Removes the child view from the parent view.Parameters:
-
viewEmber.View
Returns:
Ember.View:
receiver
removeFromParent
Syntax
Summary
Removes the view from itsparentView, if one is found. Otherwise
does nothing.
Returns:
Ember.View:
receiver
removeObserver
Syntax
removeObserver
(
public
-
key -
target -
method
Summary
Remove an observer you have previously registered on this object. Pass the same key, target, and method you passed toaddObserver() and your
target will no longer receive notifications.
renderBlock
Syntax
renderBlock
(
private
-
buffer
Summary
Called on your view when it should push strings of HTML into aEmber.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.
Parameters:
-
bufferEmber.RenderBufferThe render buffer
renderToElement
Syntax
Summary
Parameters:
-
tagNameStringThe tag of the element to create and render into. Defaults to "body".
Returns:
HTMLBodyElement:
element
reopen
Syntax
reopen
()
public
Summary
Augments a constructor's prototype with additional properties and functions:`javascript
MyObject = Ember.Object.extend({
name: 'an object'
});
o = MyObject.create();
o.get('name'); // 'an object'
MyObject.reopen({
say: function(msg){
console.log(msg);
}
})
o2 = MyObject.create();
o2.say("hello"); // logs "hello"
o.say("goodbye"); // logs "goodbye"
`
To add functions and properties to the constructor itself,
see reopenClass
reopenClass
Syntax
reopenClass
()
public
Summary
Augments a constructor's own properties and functions:`javascript
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.
`javascript
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
replaceIn
Syntax
Summary
Replaces the content of the specified parent element with this view's element. If the view does not have an HTML representation yet, the element will be generated 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 synchronizingParameters:
-
targetString | DOMElement | JQueryA selector, element, HTML string, or jQuery object
Returns:
Ember.View:
received
rerender
Syntax
rerender
()
public
Summary
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 usingappendChild,
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
Syntax
send
(
public
-
actionName -
context
Summary
Triggers a named action on theActionHandler. 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
`js
App.WelcomeRoute = Ember.Route.extend({
actions: {
playTheme: function() {
this.send('playMusic', 'theme.mp3');
},
playMusic: function(track) {
// ...
}
}
});
`
Parameters:
-
actionNameStringThe action to trigger -
contexta context to send with the action
sendAction
Syntax
sendAction
(
public
-
[action] -
[params]
Summary
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:`javascript
// 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:
`handlebars
{{! app/templates/application.hbs }}
{{play-button play=(action "musicStarted") stop=(action "musicStopped")}}
`
When the component receives a browser click event it translate this
interaction into application-specific semantics ("play" or "stop") and
calls the specified action.
`javascript
// 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.
`javascript
// app/components/next-button.js
export default Ember.Component.extend({
click() {
this.sendAction();
}
});
`
`handlebars
{{! app/templates/application.hbs }}
{{next-button action=(action "playNextSongInAlbum")}}
`
`javascript
// app/controllers/application.js
App.ApplicationController = Ember.Controller.extend({
actions: {
playNextSongInAlbum() {
...
}
}
});
`
Parameters:
-
[action]String optionalthe action to call -
[params]optionalarguments for the action
set
Syntax
Summary
Sets the provided key or path to the value. This method is generally very similar to callingobject[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.
Returns:
Object:
The passed value
setProperties
Syntax
Summary
Sets a list of properties at once. These properties are set inside a singlebeginPropertyChanges and endPropertyChanges batch, so
observers will be buffered.
`javascript
record.setProperties({ firstName: 'Charles', lastName: 'Jolley' });
`
Parameters:
-
hashObjectthe hash of keys and values to set
Returns:
Object:
The passed in hash
toggleProperty
Syntax
Summary
Set the value of a boolean property to the opposite of its current value.`javascript
starship.toggleProperty('warpDriveEngaged');
`
Parameters:
-
keyNameStringThe name of the property to toggle
Returns:
Boolean:
The new property value
toString
Syntax
Summary
Returns a string representation which attempts to provide more information than Javascript'stoString typically does, in a generic way for all Ember
objects.
`javascript
App.Person = Em.Object.extend()
person = App.Person.create()
person.toString() //=> "`
If the object's class is not defined on an Ember namespace, it will
indicate it is a subclass of the registered superclass:
`javascript
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.
`javascript
App.Teacher = App.Person.extend({
toStringExtension: function() {
return this.get('fullName');
}
});
teacher = App.Teacher.create()
teacher.toString(); //=> "`
Returns:
String:
string representation
trigger
Syntax
trigger
(
private
-
name
Summary
Override the default event firing fromEmber.Evented to
also call methods with the given name.
Parameters:
-
nameString
willDestroy
Syntax
willDestroy
()
public
Summary
Override to implement teardown.willRender
Syntax
willRender
()
public
Summary
Called before a component has been rendered, both on initial render and in subsequent rerenders.willUpdate
Syntax
willUpdate
()
public
Summary
Called when the component is about to update and rerender itself. Called only during a rerender, not during an initial render.Properties
_context
Syntax
_context
Unknown
private
Summary
Private copy of the view's template context. This can be set directly by Handlebars without triggering the observer that causes the view to be re-rendered. The context of a view is looked up as follows: 1. Supplied context (usually by Handlebars) 2. Specified controller 3.parentView's context
The code in Handlebars that overrides the _context property first
checks to see whether the view has a specified controller. This is
something of a hack and should be revisited.
actionContext
Syntax
actionContext
Unknown
private
Summary
actions
Syntax
Summary
The collection of functions, keyed by name, available on thisActionHandler 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.:
`js
App.CanDisplayBanner = Ember.Mixin.create({
actions: {
displayBanner: function(msg) {
// ...
}
}
});
App.WelcomeRoute = Ember.Route.extend(App.CanDisplayBanner, {
actions: {
playMusic: function() {
// ...
}
}
});
// 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, View or Component's action handler,
the value of the this context is the Controller, Route, View or
Component object:
`js
App.SongRoute = Ember.Route.extend({
actions: {
myAction: function() {
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:
`js
App.DebugRoute = Ember.Mixin.create({
actions: {
debugRouteInformation: function() {
console.debug("trololo");
}
}
});
App.AnnoyingDebugRoute = Ember.Route.extend(App.DebugRoute, {
actions: {
debugRouteInformation: function() {
// 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:
`js
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: function() {
// ...
if (actionShouldAlsoBeTriggeredOnParentRoute) {
return true;
}
}
}
});
`
Default: null
ariaRole
Syntax
Summary
The WAI-ARIA role of the control represented by this view. For example, a button may have a role of type 'button', or a pane may have a role of type 'alertdialog'. This property is used by assistive software to help visually challenged users navigate rich web applications. The full list of valid WAI-ARIA roles is available at: [http://www.w3.org/TR/wai-aria/roles#roles_categorization](http://www.w3.org/TR/wai-aria/roles#roles_categorization)Default: null
childViews
Syntax
Summary
Array of child views. You should never edit this array directly. Instead, useappendChild and removeFromParent.
Default: []
classNameBindings
Syntax
Summary
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.`javascript
// Applies the 'high' class to the view element
Ember.View.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.
`javascript
// Applies the 'is-urgent' class to the view element
Ember.View.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:
`javascript
// Applies the 'urgent' class to the view element
Ember.View.extend({
classNameBindings: ['isUrgent:urgent'],
isUrgent: true
});
`
This list of properties is inherited from the view's superclasses as well.
Default: []
classNames
Syntax
Summary
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
Syntax
Summary
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 theclassNames property of Ember.View.
Here is some sample code showing the difference between a concatenated
property and a normal one:
`javascript
App.BarView = Ember.View.extend({
someNonConcatenatedProperty: ['bar'],
classNames: ['bar']
});
App.FooBarView = App.BarView.extend({
someNonConcatenatedProperty: ['foo'],
classNames: ['foo']
});
var fooBarView = App.FooBarView.create();
fooBarView.get('someNonConcatenatedProperty'); // ['foo']
fooBarView.get('classNames'); // ['ember-view', 'bar', 'foo']
`
This behavior extends to object creation as well. Continuing the
above example:
`javascript
var view = App.FooBarView.create({
someNonConcatenatedProperty: ['baz'],
classNames: ['baz']
})
view.get('someNonConcatenatedProperty'); // ['baz']
view.get('classNames'); // ['ember-view', 'bar', 'foo', 'baz']
`
Adding a single property that is not an array will just add it in the array:
`javascript
var view = App.FooBarView.create({
classNames: 'baz'
})
view.get('classNames'); // ['ember-view', 'bar', 'foo', 'baz']
`
Using the concatenatedProperties property, we can tell Ember to mix the
content of the properties.
In Ember.View the classNameBindings and attributeBindings properties
are also concatenated, in addition to classNames.
This feature is available for you to use throughout the Ember object model,
although typical app developers are likely to use it infrequently. Since
it changes expectations about behavior of properties, you should properly
document its usage in each individual concatenated property (to not
mislead your users to think they can override the property in a subclass).
Default: null
context
Syntax
Summary
The object from which templates should access properties. This object will be passed to the template function each time the render method is called, but it is up to the individual function to decide what to do with it. By default, this will be the view's controller.controller
Syntax
Summary
The controller managing this view. If this property is set, it will be made available for use by the template.element
Syntax
element
DOMElement
public
Summary
Returns the current DOM element for the view.elementId
Syntax
Summary
The HTMLid of the view's element in the DOM. You can provide this
value yourself but it must be unique (just as in HTML):
`handlebars
{{my-component elementId="a-really-cool-id"}}
`
If not manually set a default value will be provided by the framework.
Once rendered an element's elementId is considered immutable and you
should never change it. If you need to compute a dynamic value for the
elementId, you should do this when the component or element is being
instantiated:
`javascript
export default Ember.Component.extend({
setElementId: Ember.on('init', function() {
var index = this.get('index');
this.set('elementId', 'component-id' + index);
})
});
`
hasBlock
Syntax
hasBlock
Unknown
public
Summary
Returns true when the component was invoked with a block template. Example (hasBlock will be false):
`hbs
{{! templates/application.hbs }}
{{foo-bar}}
{{! templates/components/foo-bar.hbs }}
{{#if hasBlock}}
This will not be printed, because no block was provided
{{/if}}
`
Example (hasBlock will be true):
`hbs
{{! templates/application.hbs }}
{{#foo-bar}}
Hi!
{{/foo-bar}}
{{! templates/components/foo-bar.hbs }}
{{#if hasBlock}}
This will be printed because a block was provided
{{yield}}
{{/if}}
`
This helper accepts an argument with the name of the block we want to check the presence of.
This is useful for checking for the presence of the optional inverse block in components.
`hbs
{{! templates/application.hbs }}
{{#foo-bar}}
Hi!
{{else}}
What's up?
{{/foo-bar}}
{{! templates/components/foo-bar.hbs }}
{{yield}}
{{#if (hasBlock "inverse")}}
{{yield to="inverse"}}
{{else}}
How are you?
{{/if}}
`
Sub-properties:
-
[blockName="default"]String optionalThe name of the block to check presence of.
hasBlockParams
Syntax
hasBlockParams
Unknown
public
Summary
Returns true when the component was invoked with a block parameter supplied. Example (hasBlockParams will be false):
`hbs
{{! templates/application.hbs }}
{{#foo-bar}}
No block parameter.
{{/foo-bar}}
{{! templates/components/foo-bar.hbs }}
{{#if hasBlockParams}}
This will not be printed, because no block was provided
{{yield this}}
{{/if}}
`
Example (hasBlockParams will be true):
`hbs
{{! templates/application.hbs }}
{{#foo-bar as |foo|}}
Hi!
{{/foo-bar}}
{{! templates/components/foo-bar.hbs }}
{{#if hasBlockParams}}
This will be printed because a block was provided
{{yield this}}
{{/if}}
`
instrumentDisplay
Syntax
Summary
Used to identify this view during debuggingisDestroyed
Syntax
isDestroyed
Unknown
public
Summary
Destroyed object property flag. if this property istrue the observers and bindings were already
removed by the effect of calling the destroy() method.
Default: false
isDestroying
Syntax
isDestroying
Unknown
public
Summary
Destruction scheduled flag. Thedestroy() 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
isVisible
Syntax
Summary
Iffalse, the view will appear hidden in DOM.
Default: null
layout
Syntax
Summary
A view may contain a layout. A layout is a regular template but supersedes thetemplate property during rendering. It is the
responsibility of the layout template to retrieve the template
property from the view (or alternatively, call Handlebars.helpers.yield,
{{yield}}) to render it in the correct location.
This is useful for a view that has a shared wrapper, but which delegates
the rendering of the contents of the wrapper to the template property
on a subclass.
layoutName
Syntax
Summary
The name of the layout to lookup if no layout is provided. By defaultEmber.View will lookup a template with this name in
Ember.TEMPLATES (a shared global object).
Default: null
mergedProperties
Syntax
Summary
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 thequeryParams property of routes.
Here is some sample code showing the difference between a merged
property and a normal one:
`javascript
App.BarRoute = Ember.Route.extend({
someNonMergedProperty: {
nonMerged: 'superclass value of nonMerged'
},
queryParams: {
page: {replace: false},
limit: {replace: true}
}
});
App.FooBarRoute = App.BarRoute.extend({
someNonMergedProperty: {
completelyNonMerged: 'subclass value of nonMerged'
},
queryParams: {
limit: {replace: false}
}
});
var fooBarRoute = App.FooBarRoute.create();
fooBarRoute.get('someNonMergedProperty');
// => { completelyNonMerged: 'subclass value of nonMerged' }
//
// Note the entire object, including the nonMerged property of
// the superclass object, has been replaced
fooBarRoute.get('queryParams');
// => {
// 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.
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
Syntax
Summary
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
tagName
Syntax
Summary
Tag name for the view's outer element. The tag name is only used when an element is first created. If you change thetagName for an element, you
must destroy and recreate the view element.
By default, the render buffer will use a <div> tag for views.
Default: null
target
Syntax
target
Unknown
private
Summary
targetObject
Syntax
Summary
If the component is currently inserted into the DOM of a parent view, this property will point to the controller of the parent view.Default: null
template
Syntax
Summary
The template used to render the view. This should be a function that accepts an optional context parameter and returns a string of HTML that will be inserted into the DOM relative to its parent view. In general, you should set thetemplateName property instead of setting
the template yourself.
templateName
Syntax
Summary
The name of the template to lookup if no template is provided. By defaultEmber.View will lookup a template with this name in
Ember.TEMPLATES (a shared global object).
Default: null