Book Image

Ext JS 3.0 Cookbook

Book Image

Ext JS 3.0 Cookbook

Overview of this book

Using Ext JS you can easily build desktop-style interfaces in your web applications. Over 400,000 developers are working smarter with Ext JS and yet most of them fail to exercise all of the features that this powerful JavaScript library has to offer. Get to grips with all of the features that you would expect with this quick and easy-to-follow Ext JS Cookbook. This book provides clear instructions for getting the most out of Ext JS with and offers many exercises to build impressive rich internet applications. This cookbook shows techniques and "patterns" for building particular interface styles and features in Ext JS. Pick what you want and move ahead. It teaches you how to use all of the Ext JS widgets and components smartly, through practical examples and exercises. Native and custom layouts, forms, grids, listviews, treeviews, charts, tab panels, menus, toolbars, and many more components are covered in a multitude of examples.The book also looks at best practices on data storage, application architecture, code organization, presenting recipes for improving themóour cookbook provides expert information for people working with Ext JS.
Table of Contents (15 chapters)
Ext JS 3.0 Cookbook
About the Author
About the Reviewer

Creating an auto-refreshing chart

Sometimes, it is desirable to have a chart that automatically refreshes its information. This recipe shows you how to implement periodic updates of a chart's data. The Crazy Stock Prices chart will display fictitious stock prices, as seen in the following screenshot:

The chart's data will refresh periodically without user intervention, as seen in the following screenshot:

How to do it...

  1. 1. Set the URL to load the chart from:

    Ext.chart.Chart.CHART_URL = '../ext3/charts.swf';
  2. 2. Create a function to generate dummy data:

    function generateData() {
    var data = [];
    var companies = ['MSFT','YHOO','GOOG','JAVA'];
    for (var i = 0; i < 4; ++i) {
    data.push([companies[i], (Math.floor(Math.random() * 11) + 1) * 10]);
    return data;
  3. 3. Define a data store to feed the chart:

    var store = new{
    fields: ['stock', 'price'],
    data: generateData()
  4. 4. Create a function that will be called periodically to refresh the data:

    function refreshData() {