Book Image

Ext JS 4 Web Application Development Cookbook

By : Andrew Duncan, Stuart Ashworth
Book Image

Ext JS 4 Web Application Development Cookbook

By: Andrew Duncan, Stuart Ashworth

Overview of this book

<p>Ext JS 4 is Sencha’s latest JavaScript framework for developing cross-platform web applications. Built upon web standards, Ext JS provides a comprehensive library of user interface widgets and data manipulation classes to turbo-charge your application’s development. Ext JS 4 builds on Ext JS 3, introducing a number of new widgets and features including the popular MVC architecture, easily customisable themes and plugin-free charting. <br /><br /><em>Ext JS 4 Web Application Development Cookbook</em> works through the framework from the fundamentals to advanced features and application design. More than 130 detailed and practical recipes demonstrate all of the key widgets and features the framework has to offer. With this book, and the Ext JS framework, learn how to develop truly interactive and responsive web applications.<br /><br />Starting with the framework fundamentals, you will work through all of the widgets and features the framework has to offer, finishing with extensive coverage of application design and code structure.<br /><br />Over 110 practical and detailed recipes describe how to create and work with forms, grids, data views, and charts. You will also learn about the best practices for structuring and designing your application and how to deal with storing and manipulating data. The cookbook structure is such that you may read the recipes in any order.<br /><br />The <em>Ext JS 4 Web Application Development Cookbook</em> will provide you with the knowledge to create interactive and responsive web applications, using real life examples.</p>
Table of Contents (19 chapters)
Ext JS 4 Web Application Development Cookbook
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Loading a tree's nodes from the server


Creating a tree in your user interface is achieved using a Tree Panel. This recipe gives you the knowledge required to create and configure a Tree Panel and load JSON data asynchronously from your server to the tree. The final tree will look like the following screenshot:

Getting ready

Make sure you have a web server installed and running on your development computer. For the purposes of this demonstration, your web server will need to serve JSON files. If your server is not capable, add a MIME type for JSON (application/json).

How to do it...

  1. Start by defining an Ext.data.TreeStore to load our data into:

    var store = Ext.create('Ext.data.TreeStore', {
        proxy: {
            type: 'ajax',
            url: 'treeData.json'
        },
        root: {
            text: 'Countries',
            expanded: true
        }
    });
  2. The treeData.json file that we are loading from contains a simple array of data, some of these objects contain nested data that will form our tree structure. A sample...