ember-two-way-binding-example

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  
  actions: {
    increaseVar(){
      this.set('variable', this.get('variable') + 1);
    }
  }
  
});

controllers.application.js

import Ember from 'ember';
import {computed} from '@ember/object';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  x: 5,
  y: 5,
  
  computed2X: computed('x', function(){
    return 2 * this.get('x');
  }),
  
  computed2Y: computed('y', function(){
    return 2 * this.get('y');
  }),
  
  actions: {
    increaseX(){
      this.set('x', this.get('x') + 1);
    },
    
    increaseY(){
      this.set('y', this.get('y') + 1);
    }
  }
  
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
two way controller x: {{x}}
<button {{action 'increaseX'}} >increase x</button>
{{my-component variable=x }}
{{my-component variable=x }}
computed2X: {{computed2X}}

<br>

one way controller y: {{y}}
<button {{action 'increaseY'}} >increase y</button>
{{my-component variable=(readonly y) }}
{{my-component variable=(readonly y) }}
computed2Y: {{computed2Y}}
<br>
{{outlet}}
<br>
<br>

templates.components.my-component.hbs

{{yield}}
component variable: {{variable}}
<button {{action 'increaseVar'}} >increase var</button>

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}