mouseleave

components.mouse-leave.js

import Ember from 'ember';

let i = 0;

export default Ember.Component.extend({
  classNames: ['mouse-leave'],
  classNameBindings: ['isOpened:is-opened'],
  left: [],
  click() {
    set(this, 'isOpened', true);
  },
  mouseLeave() {
  	this.get('left').pushObject(i++);
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  actions: {
    openMe() {
      this.toggleProperty('isOpened');
    }
  }
});

styles.app.css

body {
  margin: 12px 16px;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 12pt;
}


.my-button {
  width: 60px;
  height: 70px;
  padding: 0;
  border: none;
  background-color: red;
}
.mouse-leave {
  background-color: green;
  width: 80px;
  height: 40px !important;
}

templates.application.hbs

<br>
<br>
{{mouse-leave}}
<br>
<br>

templates.components.mouse-leave.hbs

<button class="my-button" disabled=true>Hi</button>

{{#each left as |i|}}
{{i}}
{{/each}}

twiddle.json

{
  "version": "0.13.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-data": "2.16.3"
  }
}