New Twiddle

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  actions: {
    foo() {
      alert("called");
    }
  },
  selection: [],
  appName:'Ember Twiddle'
});

application.template.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
{{x-comp modelId=1 otherFn=(action "foo") selection=(mut selection)}}
{{x-comp modelId=2 otherFn=(action "foo") selection=(mut selection)}}
<br>
<br>

twiddle.json

{
  "version": "0.5.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.2.0",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.2.0/ember-data.js",
    "ember-template-compiler": "2.2.0"
  }
}

x-comp.component.js

import Ember from 'ember';

let i = 0;

const computed = Ember.computed;

export default Ember.Component.extend({
  selected: computed("selection.[]", "modelId", function() {
    return this.get("selection").contains(this.get("modelId"));
  }),

  click(e) {
    this.get("otherFn")();
    this.addOrRemoveFromSelection();
  },

  addOrRemoveFromSelection() {
    let selection = this.get("selection"),
      modelId = this.get("modelId");

    if (selection.contains(modelId)) {
      selection.removeObject(modelId);
    } else {
      selection.addObject(modelId);
    }

    this.setSelection(selection);
  },

  setSelection(selection) {
    alert(this.get("selection.update"));
    if (typeof this.attrs.selection.update === "function") {
      this.attrs.selection.update(selection);
    }
  }

});

x-comp.template.hbs

{{#if selected}}selected{{/if}}
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