Book Image

Backbase 4 RIA Development

Book Image

Backbase 4 RIA Development

Overview of this book

Backbase is a very powerful and complex JavaScript library, with many user interface components to help make web development easier. It allows the development of Rich Internet Applications (RIA) that run within all major browsers but its powers and complexity mean that the choice of component can be overwhelming. Understanding when and how to use the right component might not always be straightforward. This book makes that easier. This is a practical book that teaches you how to use the Backbase Client Framework effectively, with a complete overview and many examples. A core developer of the framework puts the technologies used into a wider perspective of existing web standards and a seasoned software architect explains why XML-based UI definition produces better web applications. The transparent use of AJAX technologies, for example to submit forms, or to retrieve updates for data grids, can be taken for granted with the Backbase framework. Packed with examples, the book shows you how to get the most from the library of UI components, and then extend the library with its own custom language. With this book in hand, it is easy to enable AJAX within your web application. You will be able to use the Backbase framework effectively, from basic applications to complex, custom-defined UI components. This book contains a complete overview of all the UI libraries available within the Backbase framework and shows examples for each element described. The Backbase framework offers an innovative Tag Definition Language (TDL), which allows developers to create new UI components that can be used as XML elements, in the same way as using the built-in GUI library. Using TDL brings considerable development advantages, and this book explains how. Significant attention is also given to architectural aspects of designing a web-application, showing sample applications using a model-view-controller approach.
Table of Contents (16 chapters)
Backbase 4 RIA Development
Credits
About the Authors
About the Reviewers
Preface

The Backbase XML Execution Language (XEL)


The Backbase Client Framework offers XEL, an XML markup language, which can be used in many circumstances as an alternative to JavaScript. This section will introduce you to the main XEL elements.

Before we turn our attention to XEL itself, let us try to clarify when you should use JavaScript and when you should use XEL. Remember that we showed two versions of the "Hello Backbase" balloon example in Chapter 1. In both cases, they used an XEL event handler tag to describe what should happen in case the user clicks on the OK button. In the first example, the content of the element was coded in JavaScript and in the second example we used XEL. This suggests that you can use XEL or JavaScript interchangeably. Just use whatever you like better for a specific situation.

By specifying either text/javascript or application/xml (which is usually the default), you can indicate the choice you made. When making a choice, keep this in mind:

  • XEL code is usually...