Class Controller

public
import Controller from '@ember/controller';

Show:

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 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;
      }
    }
  }
});

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 Component from @ember/component.

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

import EmberObject from '@ember/object';

const Bar = EmberObject.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 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).

Destroyed object property flag.

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

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.

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:

import EmberObject from '@ember/object';

const Bar = EmberObject.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 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).

The controller's current model. When retrieving or modifying a controller's model, this property should be used instead of the content property.

Defines which query parameters the controller accepts. If you give the names ['category','page'] it will bind the values of these query parameters to the variables this.category and this.page.

By default, query parameters are parsed as strings. This may cause unexpected behavior if a query parameter is used with toggleProperty, because the initial value set for param=false will be the string "false", which is truthy.

To avoid this, you may specify that the query parameter should be parsed as a boolean by using the following verbose form with a type property:

  queryParams: [{
    category: {
      type: 'boolean'
    }
  }]

Available values for the type parameter are 'boolean', 'number', 'array', and 'string'. If query param type is not specified, it will default to 'string'.

The object to which actions from the view should be sent.

For example, when a Handlebars template uses the {{action}} helper, it will attempt to send the action to the view's controller's target.

By default, the value of the target property is set to the router, and is injected when a controller is instantiated. This injection is applied as part of the application's initialization process. In most cases the target property will automatically be set to the logical consumer of actions for the controller.