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Class TextArea public


Extends: Component
Uses: Ember.TextSupport
Defined in: packages/ember-glimmer/lib/components/text_area.ts:201
Module: @ember/component
import TextArea from '@ember/component/text-area';

The 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.


Methods

$ (selector) : JQuery public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:874

selector
String

a jQuery-compatible selector string

returns
JQuery

the jQuery object for the DOM node

Returns a jQuery object for this component'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 component.$('li') will return a jQuery object containing all of the li elements inside the DOM element of this component.

addObserver (key, target, method) : Ember.Observable public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:331

key
String

The key to observe

target
Object

The target object to invoke

method
String|Function

The method to invoke

returns
Ember.Observable

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.

Observer Methods

Observer methods have the following signature:

app/components/my-component.js
import Component from '@ember/component';

export default Component.extend({
  init() {
    this._super(...arguments);
    this.addObserver('foo', this, 'fooDidChange');
  },

  fooDidChange(sender, key, value, rev) {
    // your code
  }
});

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.

Usually you will not need the value 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

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:489

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.

decrementProperty (keyName, decrement) : Number public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:452

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.

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

destroy : EmberObject public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:445

returns
EmberObject

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

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:757

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

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:777

Available since v1.13.0

Called after a component has been rendered, both on initial render and in subsequent rerenders.

didUpdate public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:841

Available since v1.13.0

Called when the component has updated and rerendered itself. Called only during a rerender, not during an initial render.

didUpdateAttrs public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:809

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.

get (keyName) : Object public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:94

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:

fullName: Ember.computed('firstName', 'lastName', function() {
  return this.get('firstName') + ' ' + this.get('lastName');
})

When you call get on a computed property, the function will be called and the return value will be returned instead of the function itself.

Unknown Properties

Likewise, if you try to call get on a property whose value is undefined, the unknownProperty() method will be called on the object. If this method returns any value other than undefined, it will be returned instead. This allows you to implement "virtual" properties that are not defined upfront.

getProperties (list) : Object public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:137

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:

record.getProperties('firstName', 'lastName', 'zipCode');
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }

is equivalent to:

record.getProperties(['firstName', 'lastName', 'zipCode']);
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }

getWithDefault (keyName, defaultValue) : Object public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:414

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.

person.getWithDefault('lastName', 'Doe');

has (name) : Boolean public

Module: @ember/component

Inherited from Evented packages/ember-runtime/lib/mixins/evented.js:145

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

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:432

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.

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

init public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:210

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

Example:

const Person = Ember.Object.extend({
  init() {
    alert(`Name is ${this.get('name')}`);
  }
});

let steve = Person.create({
  name: 'Steve'
});

// alerts 'Name is Steve'.

NOTE: If you do override init for a framework class like Ember.View, be sure to call this._super(...arguments) in your init declaration! If you don't, Ember may not have an opportunity to do important setup work, and you'll see strange behavior in your application.

notifyPropertyChange (keyName) : Observable public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:316

keyName
String

The property key to be notified about.

returns
Observable

Convenience method to call propertyWillChange and propertyDidChange in succession.

off (name, target, method) : public

Module: @ember/component

Inherited from Evented packages/ember-runtime/lib/mixins/evented.js:130

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

Module: @ember/component

Inherited from Evented packages/ember-runtime/lib/mixins/evented.js:55

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.

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

Module: @ember/component

Inherited from Evented packages/ember-runtime/lib/mixins/evented.js:81

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

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:645

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) : Ember.Observable public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:382

key
String

The key to observe

target
Object

The target object to invoke

method
String|Function

The method to invoke

returns
Ember.Observable

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.

rerender public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:122

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

Module: @ember/component

Inherited from Ember.ActionHandler packages/ember-runtime/lib/mixins/action_handler.js:167

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

app/routes/welcome.js
import Route from '@ember/routing/route';

export default Route.extend({
  actions: {
    playTheme() {
      this.send('playMusic', 'theme.mp3');
    },
    playMusic(track) {
      // ...
    }
  }
});

sendAction (action, params) public

Module: @ember/component

Inherited from Ember.ActionSupport packages/ember-views/lib/mixins/action_support.js:27

action
String

the action to call

params
*

arguments for the action

Calls an 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:

app/components/play-button.js
import Component from '@ember/component';

export default 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:

{{! 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.

app/controller/application.js
import Controller from '@ember/controller';

export default 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.

app/components/next-button.js
import Component from '@ember/component';

export default Component.extend({
  click() {
    this.sendAction();
  }
});
{{! app/templates/application.hbs }}
{{next-button action=(action "playNextSongInAlbum")}}
app/controllers/application.js
import Controller from '@ember/controller';

export default Controller.extend({
  actions: {
    playNextSongInAlbum() {
      ...
    }
  }
});

set (keyName, value) : Object public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:162

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.

record.set("key", value);

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

Computed Properties

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

Unknown Properties

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

Property Observers

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

setProperties (hash) : Object public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:211

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.

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

toString : String public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:498

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.

const Person = Ember.Object.extend()
person = Person.create()
person.toString() //=> "<Person:ember1024>"

If the object's class is not defined on an Ember namespace, it will indicate it is a subclass of the registered superclass:

const Student = Person.extend()
let student = Student.create()
student.toString() //=> "<(subclass of Person):ember1025>"

If the method toStringExtension is defined, its return value will be included in the output.

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

toggleProperty (keyName) : Boolean public

Module: @ember/component

Inherited from Observable packages/ember-runtime/lib/mixins/observable.js:472

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.

starship.toggleProperty('warpDriveEngaged');

trigger (name, args) public

Module: @ember/component

Inherited from Evented packages/ember-runtime/lib/mixins/evented.js:107

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.

person.on('didEat', function(food) {
  console.log('person ate some ' + food);
});

person.trigger('didEat', 'broccoli');

// outputs: person ate some broccoli

willDestroy public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:471

Override to implement teardown.

willRender public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:793

Available since v1.13.0

Called before a component has been rendered, both on initial render and in subsequent rerenders.

willUpdate public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:825

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.

Properties

actions public

Module: @ember/component

Inherited from Ember.ActionHandler packages/ember-runtime/lib/mixins/action_handler.js:22

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

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

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

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

app/mixins/can-display-banner.js
import Mixin from '@ember/mixin';

export default Mixin.create({
  actions: {
    displayBanner(msg) {
      // ...
    }
  }
});
app/routes/welcome.js
import Route from '@ember/routing/route';
import CanDisplayBanner from '../mixins/can-display-banner';

export default Route.extend(CanDisplayBanner, {
  actions: {
    playMusic() {
      // ...
    }
  }
});

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

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

app/routes/song.js
import Route from '@ember/routing/route';

export default Route.extend({
  actions: {
    myAction() {
      this.controllerFor("song");
      this.transitionTo("other.route");
      ...
    }
  }
});

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

Take for example the following routes:

app/mixins/debug-route.js
import Mixin from '@ember/mixin';

export default Ember.Mixin.create({
  actions: {
    debugRouteInformation() {
      console.debug("It's a-me, console.debug!");
    }
  }
});
app/routes/annoying-debug.js
import Route from '@ember/routing/route';
import DebugRoute from '../mixins/debug-route';

export default Route.extend(DebugRoute, {
  actions: {
    debugRouteInformation() {
      // also call the debugRouteInformation of mixed in 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:

app/router.js
Router.map(function() {
  this.route("album", function() {
    this.route("song");
  });
});
app/routes/album.js
import Route from '@ember/routing/route';

export default Route.extend({
  actions: {
    startPlaying: function() {
    }
  }
});
app/routes/album-song.js
import Route from '@ember/routing/route';

export default Route.extend({
  actions: {
    startPlaying() {
      // ...

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

ariaRole public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:681

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

attributeBindings public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:18

A list of properties of the view to apply as attributes. If the property is a string value, the value of that string will be applied as the value for an attribute of the property's name.

The following example creates a tag like <div priority="high" />.

app/components/my-component.js
import Component from '@ember/component';

export default Component.extend({
  attributeBindings: ['priority'],
  priority: 'high'
});

If the value of the property is a Boolean, the attribute is treated as an HTML Boolean attribute. It will be present if the property is true and omitted if the property is false.

The following example creates markup like <div visible />.

app/components/my-component.js
import Component from '@ember/component';

export default Component.extend({
  attributeBindings: ['visible'],
  visible: true
});

If you would prefer to use a custom value instead of the property name, you can create the same markup as the last example with a binding like this:

app/components/my-component.js
import Component from '@ember/component';

export default Component.extend({
  attributeBindings: ['isVisible:visible'],
  isVisible: true
});

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

classNameBindings public

Module: @ember/component

Inherited from Ember.ClassNamesSupport packages/ember-views/lib/mixins/class_names_support.js:37

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.

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

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

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

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

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

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

classNames public

Module: @ember/component

Inherited from Ember.ClassNamesSupport packages/ember-views/lib/mixins/class_names_support.js:25

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.

concatenatedProperties public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:248

Defines the properties that will be concatenated from the superclass (instead of overridden).

By default, when you extend an Ember class a property defined in the subclass overrides a property with the same name that is defined in the superclass. However, there are some cases where it is preferable to build up a property's value by combining the superclass' property value with the subclass' value. An example of this in use within Ember is the classNames property of Ember.View.

Here is some sample code showing the difference between a concatenated property and a normal one:

const Bar = Ember.Object.extend({
  // Configure which properties to concatenate
  concatenatedProperties: ['concatenatedProperty'],

  someNonConcatenatedProperty: ['bar'],
  concatenatedProperty: ['bar']
});

const FooBar = Bar.extend({
  someNonConcatenatedProperty: ['foo'],
  concatenatedProperty: ['foo']
});

let fooBar = FooBar.create();
fooBar.get('someNonConcatenatedProperty'); // ['foo']
fooBar.get('concatenatedProperty'); // ['bar', 'foo']

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

let fooBar = FooBar.create({
  someNonConcatenatedProperty: ['baz'],
  concatenatedProperty: ['baz']
})
fooBar.get('someNonConcatenatedProperty'); // ['baz']
fooBar.get('concatenatedProperty'); // ['bar', 'foo', 'baz']

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

let fooBar = FooBar.create({
  concatenatedProperty: 'baz'
})
view.get('concatenatedProperty'); // ['bar', 'foo', 'baz']

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

In Ember.Component the classNames, classNameBindings and attributeBindings properties are concatenated.

This feature is available for you to use throughout the Ember object model, although typical app developers are likely to use it infrequently. Since it changes expectations about behavior of properties, you should properly document its usage in each individual concatenated property (to not mislead your users to think they can override the property in a subclass).

element public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:147

Returns the current DOM element for the view.

elementId public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:886

The HTML id of the component's element in the DOM. You can provide this value yourself but it must be unique (just as in HTML):

{{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:

export default Component.extend({
  init() {
    this._super(...arguments);

    var index = this.get('index');
    this.set('elementId', `component-id${index}`);
  }
});

isDestroyed public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:395

Destroyed object property flag.

if this property is true the observers and bindings were already removed by the effect of calling the destroy() method.

isDestroying public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:420

Destruction scheduled flag. The destroy() method has been called.

The object stays intact until the end of the run loop at which point the isDestroyed flag is set.

isVisible public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:915

If false, the view will appear hidden in DOM.

layout public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:857

Layout can be used to wrap content in a component.

mergedProperties public

Module: @ember/component

Inherited from CoreObject packages/ember-runtime/lib/system/core_object.js:321

Defines the properties that will be merged from the superclass (instead of overridden).

By default, when you extend an Ember class a property defined in the subclass overrides a property with the same name that is defined in the superclass. However, there are some cases where it is preferable to build up a property's value by merging the superclass property value with the subclass property's value. An example of this in use within Ember is the queryParams property of routes.

Here is some sample code showing the difference between a merged property and a normal one:

const Bar = Ember.Object.extend({
  // Configure which properties are to be merged
  mergedProperties: ['mergedProperty'],

  someNonMergedProperty: {
    nonMerged: 'superclass value of nonMerged'
  },
  mergedProperty: {
    page: { replace: false },
    limit: { replace: true }
  }
});

const FooBar = Bar.extend({
  someNonMergedProperty: {
    completelyNonMerged: 'subclass value of nonMerged'
  },
  mergedProperty: {
    limit: { replace: false }
  }
});

let fooBar = FooBar.create();

fooBar.get('someNonMergedProperty');
// => { completelyNonMerged: 'subclass value of nonMerged' }
//
// Note the entire object, including the nonMerged property of
// the superclass object, has been replaced

fooBar.get('mergedProperty');
// => {
//   page: {replace: false},
//   limit: {replace: false}
// }
//
// Note the page remains from the superclass, and the
// `limit` property's value of `false` has been merged from
// the subclass.

This behavior is not available during object create calls. It is only available at extend time.

In Ember.Route the queryParams property is merged.

This feature is available for you to use throughout the Ember object model, although typical app developers are likely to use it infrequently. Since it changes expectations about behavior of properties, you should properly document its usage in each individual merged property (to not mislead your users to think they can override the property in a subclass).

positionalParams public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:696

Available since v1.13.0

Enables components to take a list of parameters as arguments. For example, a component that takes two parameters with the names name and age:

app/components/my-component.js
import Component from '@ember/component';

let MyComponent = Component.extend();

MyComponent.reopenClass({
  positionalParams: ['name', 'age']
});

export default MyComponent;

It can then be invoked like this:

{{my-component "John" 38}}

The parameters can be referred to just like named parameters:

Name: {{name}}, Age: {{age}}.

Using a string instead of an array allows for an arbitrary number of parameters:

app/components/my-component.js
import Component from '@ember/component';

let MyComponent = Component.extend();

MyComponent.reopenClass({
  positionalParams: 'names'
});

export default MyComponent;

It can then be invoked like this:

{{my-component "John" "Michael" "Scott"}}

The parameters can then be referred to by enumerating over the list:

{{#each names as |name|}}{{name}}{{/each}}

tagName public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:373

Tag name for the view's outer element. The tag name is only used when an element is first created. If you change the tagName for an element, you must destroy and recreate the view element.

By default, the render buffer will use a <div> tag for views.

Events

didInsertElement public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:311

Called when the element of the view has been inserted into the DOM. Override this function to do any set up that requires an element in the document body.

When a view has children, didInsertElement will be called on the child view(s) first and on itself afterwards.

didReceiveAttrs public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:767

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

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:785

Available since v1.13.0

Called after a component has been rendered, both on initial render and in subsequent rerenders.

didUpdate public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:849

Available since v1.13.0

Called when the component has updated and rerendered itself. Called only during a rerender, not during an initial render.

didUpdateAttrs public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:817

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.

willClearRender public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:324

Called when the view is about to rerender, but before anything has been torn down. This is a good opportunity to tear down any manual observers you have installed based on the DOM state

willDestroyElement public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:348

Called when the element of the view is going to be destroyed. Override this function to do any teardown that requires an element, like removing event listeners.

Please note: any property changes made during this event will have no effect on object observers.

willInsertElement public

Module: @ember/component

Inherited from Ember.ViewMixin packages/ember-views/lib/mixins/view_support.js:303

Called when a view is going to insert an element into the DOM.

willRender public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:801

Available since v1.13.0

Called before a component has been rendered, both on initial render and in subsequent rerenders.

willUpdate public

Module: @ember/component

Inherited from Component packages/ember-glimmer/lib/component.ts:833

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.

On this page


Methods

  • $
  • addObserver
  • cacheFor
  • decrementProperty
  • destroy
  • didReceiveAttrs
  • didRender
  • didUpdate
  • didUpdateAttrs
  • get
  • getProperties
  • getWithDefault
  • has
  • incrementProperty
  • init
  • notifyPropertyChange
  • off
  • on
  • one
  • readDOMAttr
  • removeObserver
  • rerender
  • send
  • sendAction
  • set
  • setProperties
  • toString
  • toggleProperty
  • trigger
  • willDestroy
  • willRender
  • willUpdate

Properties

  • actions
  • ariaRole
  • attributeBindings
  • classNameBindings
  • classNames
  • concatenatedProperties
  • element
  • elementId
  • isDestroyed
  • isDestroying
  • isVisible
  • layout
  • mergedProperties
  • positionalParams
  • tagName

Events

  • didInsertElement
  • didReceiveAttrs
  • didRender
  • didUpdate
  • didUpdateAttrs
  • willClearRender
  • willDestroyElement
  • willInsertElement
  • willRender
  • willUpdate
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