Backbone.Handlebars

Extension for better integration between Backbone.js and Handlebars.js.

Features

Backbone.View#renderTemplate

var PostView = Backbone.View.extend({
  template: Handlebars.compile('<h1>{{title}}</h1><p>{{text}}</p>'),
  render: function() {
    return this.renderTemplate(model);
  }
});

view = new PostView({model: {title: 'Title', text: 'Text'}});
$('body').append(view.render().el);

This will just render:

<div>
  <h1>Title</h1>
  <p>Text</p>
</div>

Or you can just use the new render method:

var PostView = Backbone.View.extend({
  template: Handlebars.compile('<h1>{{title}}</h1><p>{{text}}</p>'),
  templateData: function() {
    return model;
  }
});

view = new PostView({model: {title: 'Title', text: 'Text'}});
$('body').append(view.render().el);

The method templateData provides data that will be passed to the template for rendering.

You can also pass templateData directly as an object:

var PostView = Backbone.View.extend({
  template: Handlebars.compile('<h1>{{title}}</h1><p>{{text}}</p>'),
  templateData: {
    title: 'Title',
    text: 'Text'
  }
});

$('body').append(new PostView.render().el);

{{view}} helper

The real deal about using renderTemplate is that you can declare and render sub-views in your templates:

var PurchaseButton = Backbone.View.extend({
  tagName: 'button',
  events: {
    'click': 'purchaseProduct'
  },
  purchaseProduct: function() {
    // some code here
  },
  render: function() {
    this.$el.html('Purchase');
  }
});

var ProductView = Backbone.View.extend({
  template: Handlebars.compile('<h1>{{title}}</h1><p>Price: {{price}}</p>{{view "PurchaseButton"}}'),
  render: function() {
    this.renderTemplate(this.model);
  }
});

var view = new ProductView({model: {title: "Product", price: "$0.99"}});
$('body').append(view.render().el);

This will just render:

<div>
  <h1>Product</h1>
  <p>Price $0.99</p>
  <button>Purchase</button>
</div>

The cool thing is that, PurchaseButton's purchaseProduct method will be call when the button is clicked. Because {{view}} keeps the event-bindings of the view it rendered.

{{view}} features:

Nested view names.

// this will render the app.views.PostView
{{view "app.views.PostView"}}

Passing parameters to the view:

{{view "PostView" model=post tagName="article"}}
// same as
view = new PostView({model: post, tagName: 'article'});
view.render()

Overwriting existing view template:

// with given view
var ProductView = Backbone.View.extends({
  tempalte: Handlebars.template('...not...important...now...'),
  render: function() {
    this.renderTemplate();
  }
});

{{#view "ProductView"}}
  This will be rendered by the renderTemplate of ProductView
{{/view}}

This is equivalent of you writing:

var view = new ProductView();
view.template = Handlebars.compile('This will be rendered by the renderTemplate of ProductView');
view.render();

Notes: you will have to use renderTemplate in your view for this to work.

{{views}} helper

In a lot of cases you need to render more than one view. In those cases you can use the {{views}} helper:

var NumberView = Backbone.extend({
  render: function() {
    this.$el.html(this.model);
  }
});

var NumberListsView = Backbone.extend({
  template: Handlebars.compile("<ul>{{views NumberView models tagName}}</ul>"),
  render: function() {
    this.renderTemplate({models: [1,2,3,4,5]});
  }
});

var view = new NumberListsView();
view.render();

result in:

<ul>
  <li>1</li>
  <li>2</li>
  <li>3</li>
  <li>4</li>
  <li>5</li>
</ul>

The {{views}} helper have the same features as the {{view}} helper.

Backbone.View#renderedSubViews

If you need to access the rendered sub-views you can do it by calling renderedSubViews methods.

var view = new Backbone.View.extend({
  template: Handlebars.compile('{{view SubView}}{{view SubView}}'),
  render: function() {
    this.renderTemplate();
  }
});

view.render();
view.renderedSubViews(); // returns two instances of SubView

Bonus feature: killing ghost views

If you have a view which had rendered several sub-views via {{view}} helpers. When you remove the parent view Backbone.Handlebars will also remove and clear all references to the sub-views.

var view = new Backbone.View.extend({
  template: Handlebars.compile('{{view SubView}}'),
  render: function() {
    this.renderTemplate();
  }
});

view.render();
view.remove(); // this will also call the SubView#remove method

Installing

Installing

You can get Backbone.Handlebars in several ways:

• copy lib/backbone_handlebars.js into your project
• copy src/backbone_handlebars.coffee into your project if you are using CoffeeScript
• via Bower - bower install Backbone.Handlebars from your console
• adding Backbone.Handlebars as your bower dependency

Requirements

Backbone.js - 0.9.2+
Handlebars - 1.0+

Running the tests

Install bower developer dependencies - bower install.

Just open - test/runner.html.

Contributing

Every fresh idea and contribution will be highly appreciated.

If you are making changes please do so in the coffee files. And then compile them with:

cake build

License

MIT License.