Ember.js Dynamic Model Properties

Question

Ember.js (and Ember Data) allows me to specify properties of a model, such as id, label and description. But I allow my users to add their own properties to any model, which are obviously impossible for me to know about. Is there any way I can dynamically add properties to a model at runtime? (And more importantly, will Ember.js recognize changes on those properties and save them?)

Darshan Sawardekar Darshan Sawardekar · Accepted Answer · 2013-07-11T13:47:44

Ember defines object properties via Ember.defineProperty. The signature is Ember.defineProperty(object, propertyName, function). For instance to define a lorem property backed by _lorem, you can use

Ember.defineProperty(this, 'lorem', 
  Ember.computed(function (key, value) {
    if (value) {
      this.set('_lorem', value);
      return value;
    } else {
      return this.get('_lorem');
    }
  }  
));

You can call this method based in a user input handler when the propertyName is dynamic. This sort of thing is best suited for extending the Meta object system. Caution is advised, especially with user input!

Ember.js Dynamic Model Properties

1 Answers