Awesome model binding for Backbone.js

Inspired by Brad Phelan, Knockout.js' data-binding capabilities, and Brandon Satrom's desire to keep UJS alive.

It's easy to get up and running. You only need to have Backbone (including underscore.js - a requirement for Backbone) and jQuery in your page before including the backbone.modelbining plugin.

• Backbone.js v0.5.1 or higher
• jQuery v1.6.2 or higher

This is a plugin for Backbone.js and is built and tested against Backbone v0.5.1. It also uses jQuery to perform most of the bindng and manipulations, and is built and tested against v1.6.1. However, I am currently using this plugin in a production application with Backbone v0.3.3 and jQuery v1.5.1.

At this point, I make no guarantees of it working with any version of Backbone or jQuery, other than what it has been built and tested against. It works for me, so it may work for you with versions other than what is stated

Download the backbone.modelbinding.js file from this github repository and copy it into your javascripts folder. Add the needed <script> tag to bring the plugin into any page that wishes to use it. Be sure to include the modelbinding file after the backbone.js file.

Your Backbone view must have an el defined and the render method of your view needs to execute the bindings that you define

SomeView = Backbone.View.extend({
  el: "#someElement",

  render: function(){
    // ... render your form here

    // execute the defined bindings
    Backbone.ModelBindings.call(this);
  }
});

Automatic bi-directional binding between your form input and your model.

The convention based binding requires no additional configuration or code in your view, other than calling the Backbone.Modelbindings.call(this); as noted above. With the conventions binding, your <input> fields will be bound to the views model by the id of the input.

For example:

// something.html

<input id='name'>

// something.js

SomeModel = Backbone.Model.extend();

SomeView = Backbone.View.extend({
  render: function(){
    // ... render your form here

    // execute the defined bindings
    Backbone.ModelBindings.call(this);
  }
});

model = new SomeModel();
view = new SomeView({model: model});

model.set({name: "some name"});

In this example, when model.set is called to set the name, "some name" will appear in the #name input field. Similarly, when the #name input field is changed, the value entered into that field will be sent to the model's name attribute.

At this point, only <input> and <select> fields are handled. Other form field types should come soon, though.

Non-conventional, bi-directional binding between your form input and your model.

Add formBindings document to you view, to specify the bindings you want to use. The format is the same as the Backbone view events

SomeView = Backbone.View.extend({
  formBindings: {
    "change #someInput": "a_field"
  }
});

The input element must be settable via the jQuery val method. You can specify any valid jQuery event to monitor for a change, though.

Now when you type into the form input, your model's fields will be updated automatically. When your model's fields are changed, the form input will update automatically. And, when you render the view, the field will be populated with the value that exists in the model at rendering time.

Model -> HTML element binding for your model's field value changes.

Add an 'htmlBindings' document to your view, to specify the bindings you want to use. The format is to list the html element selector on the left, and the model's field on the right.

SomeView = Backbone.View.extend({
  htmlBindings: {
    "#someElement": "a_field"
  }
});

Now when the model's a_field is changed, the html element #someElement will have it's contents replaced by the value that is entered into the model's a_field field.

Note: htmlBindings is experimental as I don't have an actual use for it right now. I put it in because it was easy and it might inspire some other ideas at some point.

backbone.modelbinding is still in the early stages and has limited functionality. Although functionality is being built with unit tests, in a test-first manner, there is no guarantee that it will work the way you want it to or expect it to. Use at your own risk.

Copyright (c) 2011 Derick Bailey

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.