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

Creating custom VTypes


We have seen in the previous recipe how to use VTypes to apply more advanced validation to our form's fields. The built-in VTypes provided by the framework are excellent but we will often want to create custom implementations to impose more complex and domain specific validation to a field.

We will walkthrough creating a custom VType to be applied to our telephone number field to ensure it is in the format that a telephone number should be.

Although our telephone number field is split into two (the first field for the area code and the second for the rest of the number), for this example we will combine them so our VType is more comprehensive.

For this example, we will be validating a very simple, strict telephone number format of "0777-777-7777".

How to do it...

  1. We start by defining our VType's structure. This consists of a simple object literal with three properties. A function called telNumber and two strings called telNumberText (which will contain the error message...