Book Image

BlackBerry Java Application Development

Book Image

BlackBerry Java Application Development

Overview of this book

BlackBerry Smartphone was once the domain of jet-setting business users with power suits. Now you can hardly go anywhere without seeing someone using a BlackBerry to check their messages or make a call. It's this kind of explosive growth that makes the BlackBerry ecosystem a great place to develop and market applications through the BlackBerry App World store—this book shows you how to do just that! This step-by-step guide gives you a hands-on experience of developing innovative Java applications for your BlackBerry. With the help of this book, you will learn to build your own applications to illustrate the platform, and the various capabilities that developers can use in their programs. It explores the powers of Blackberry and helps you develop professional and impressive Java applications. The book teaches how to write rich, interactive, and smart BlackBerry applications in Java. It expects the readers to know Java but not Java Mobile or the BlackBerry APIs. We will learn to build rich, interactive, and smart Java applications for the BlackBerry. The book will cover UI programming, data storage, programming network, and internet API apps. As we move on, we will learn more about the BlackBerry's device features, such as messaging, GPS, multimedia, contacts and calendar, and so on.This book also helps you build your own applications to illustrate the platform, and the various capabilities that developers can use in their programs.
Table of Contents (18 chapters)
BlackBerry Java Application Development
Credits
About the Author
Acknowledgement
About the Reviewers
Preface

Time for action - disabling the "save" dialog


  1. 1. Add the following method to the TipCalcMainScreen class.

    // return true to allow an exit without displaying the save prompt
    protected boolean onSavePrompt()
    {
    return true;
    }
    

What just happened?

Remember, when talking about overriding the makeMenu method that sometimes you want to call the same method of the super class (that is, super.makeMenu), and sometimes you don't. This was an example of a time when you don't want to call the super class because you wanted to interrupt what the super class was doing. In this case, simply returning true gave you the desired behavior.

Have a go hero - expanding TipCalc even more

Now that you've covered some of the basics of your first application, why not try to take it a step further and refine it even further on your own. One of the biggest problems with this application is the fact that you can calculate the tip at only one percentage. Sometimes you want to tip different amounts based on the quality of service...