mvc of js

http://alexatnet.com/articles/model-view-controller-mvc-javascript

 

The article demonstrates how to apply the Model-View-Controller software design pattern while developing a simple JavaScript component.

I like JavaScript because it is one of the most flexible languages in the world. It supports wide range of the programming styles and techniques, but such flexibility comes with danger - it is very easy for the JavaScript project to become a messy heap if the practices or design patterns are applied in a wrong way or inconsistently.

My goal for this article is to demonstrate how to apply the Model-View-Controller pattern while developing a simple JavaScript component. The component is a kind of the HTML ListBox ("select" HTML tag) control with an editable list of items: the user should be able to select and remove items and add new items into the list. The component will consist of three classes that corresponds to the parts of the Model-View-Controller design pattern.

I hope, this article will be a good reading for you, but it would be much better if you consider to run the examples and adapt them to you needs. I believe you have everything to create and run JavaScript programs: brains, hands, text editor, and an Internet Browser (Google Chrome, for example).

The Model-View-Controller pattern requires some description here. As you may know, the name of the pattern is based on the names of its main parts: Model, which stores an application data model; View, which renders Model for an appropriate representation; and Controller, which updates Model. Wikipedia defines typical components of the Model-View-Controller architecture as follows:

• Model - The domain-specific representation of the information on which the application operates. The model is another name for the domain layer. Domain logic adds meaning to raw data (e.g., calculating if today is the user's birthday, or the totals, taxes and shipping charges for shopping cart items).
• View - Renders the model into a form suitable for interaction, typically a user interface element. MVC is often seen in web applications, where the view is the HTML page and the code which gathers dynamic data for the page.
• Controller - Processes and responds to events, typically user actions, and invokes changes on the model and perhaps the view.

The data of the component is just a list of items, in which one particular item can be selected and deleted. So, the model of the component is very simple - it consists of an array and a selected item index; and here it is: