The Object Model:

So one of the first things I found out about is everything in Ember extends from one base object which is know as simply, Ember.Object. You can see this clearly throughout the app, even the views, and controllers, Ember.View, Ember.Controller, respectively, follow this rule. The basic Ember.Object, has it uses, things like creating service objects that handle some specific logic (like creating methods on models in rails).

Since everything in Ember extends from the basic Ember.Object, any time we want to create our own object “class” we simply call extend on Ember.Object , and then go about as we would creating a regular javascript object.

App.User = Ember.Object.extend(

isHuman: false,

isDalek: true

)

We pre-fix with App because Ember needs a variable to keep all data for the application in and Ember developers have come up with the convention of App as the variable name. Coming from a rails background, this is most welcome to me!

Along side with being able to have functions, objects may also have a special type of function you can declare as a computed property, meaning ember will automatically call the function and feed you the value. This really comes in handy when you want to grab from existing attributes on the object to manipulate the data in some way. A good example exists on the ember docs:

App.Person = Ember.Object.extend({
  // these will be supplied by `create`
  firstName: null,
  lastName: null,

  fullName: function() {
    return this.get('firstName') + ' ' + this.get('lastName');
  }.property('firstName', 'lastName')
});

var ironMan = App.Person.create({
  firstName: "Tony",
  lastName:  "Stark"
});

ironMan.get('fullName'); // "Tony Stark"

Here they use it to call ironMan.get(‘fullname’); the property when called with get, executes the function and returns us the combined attributes of firstName and lastName. I can only imagine how useful this might become in future applications.

A second interesting interesting note about Ember.Objects is they have a property observer which can be set inside as a property itself. It’s job will be to watch the value of another property and fire off a function if it’s value changes. This can also be hooked up to a computer property. Amazing! Very cool functions. Back to the ember docs for a good example.

Person = Ember.Object.extend({
  // these will be supplied by `create`
  firstName: null,
  lastName: null,

  fullName: function() {
    var firstName = this.get('firstName');
    var lastName = this.get('lastName');

    return firstName + ' ' + lastName;
  }.property('firstName', 'lastName'),

  fullNameChanged: function() {
    // deal with the change
  }.observes('fullName').on('init')
});

var person = Person.create({
  firstName: 'Yehuda',
  lastName: 'Katz'
});

person.set('firstName', 'Brohuda');