ContributorsLast modified on: Mar 25, 2016
farhan687

You can respond to user events on your component like double-clicking, hovering, and key presses through event handlers. Simply implement the name of the event you want to respond to as a method on your component.

For example, imagine we have a template like this:

{{#double-clickable}}
  This is a double clickable area!
{{/double-clickable}}

Let’s implement double-clickable such that when it is clicked, an alert is displayed:

export default Ember.Component.extend({
  doubleClick: function() {
    alert("DoubleClickableComponent was clicked!");
  }
});

Browser events may bubble up the DOM which potentially target parent component(s) in succession. To enable bubbling return true; from the event handler method in your component.

export default Ember.Component.extend({
  doubleClick: function() {
    Ember.Logger.info("DoubleClickableComponent was clicked!");
    return true;
  }
});

See the list of event names at the end of this page. Any event can be defined as an event handler in your component.

Sending Actions

In some cases your component needs to define event handlers, perhaps to support various draggable behaviors. For example, a component may need to send an id when it receives a drop event:

{{drop-target action="didDrop"}}

You can define the component’s event handlers to manage the drop event. And if you need to, you may also stop events from bubbling, by using return false;.

export default Ember.Component.extend({
  attributeBindings: ['draggable'],
  draggable: 'true',

  dragOver: function() {
    return false;
  },

  drop: function(event) {
    let id = event.dataTransfer.getData('text/data');
    this.sendAction('action', id);
  }
});

Event Names

The event handling examples described above respond to one set of events. The names of the built-in events are listed below. Custom events can be registered by using Ember.Application.customEvents.

Touch events:

  • touchStart
  • touchMove
  • touchEnd
  • touchCancel

Keyboard events

  • keyDown
  • keyUp
  • keyPress

Mouse events

  • mouseDown
  • mouseUp
  • contextMenu
  • click
  • doubleClick
  • mouseMove
  • focusIn
  • focusOut
  • mouseEnter
  • mouseLeave

Form events:

  • submit
  • change
  • focusIn
  • focusOut
  • input

HTML5 drag and drop events:

  • dragStart
  • drag
  • dragEnter
  • dragLeave
  • dragOver
  • dragEnd
  • drop