Book Image

Eclipse 4 Plug-in Development by Example : Beginner's Guide

By : Dr Alex Blewitt
Book Image

Eclipse 4 Plug-in Development by Example : Beginner's Guide

By: Dr Alex Blewitt

Overview of this book

<p>As a highly extensible platform, Eclipse is used by everyone from independent software developers to NASA. Key to this is Eclipse’s plug-in ecosystem, which allows applications to be developed in a modular architecture and extended through its use of plug-ins and features.<br /><br />"Eclipse 4 Plug-in Development by Example Beginner's Guide" takes the reader through the full journey of plug-in development, starting with an introduction to Eclipse plug-ins, continued through packaging and culminating in automated testing and deployment. The example code provides simple snippets which can be developed and extended to get you going quickly.</p> <p>This book covers basics of plug-in development, creating user interfaces with both SWT and JFace, and interacting with the user and execution of long-running tasks in the background.</p> <p>Example-based tasks such as creating and working with preferences and advanced tasks such as well as working with Eclipse’s files and resources. A specific chapter on the differences between Eclipse 3.x and Eclipse 4.x presents a detailed view of the changes needed by applications and plug-ins upgrading to the new model. Finally, the book concludes on how to package plug-ins into update sites, and build and test them automatically.</p>
Table of Contents (19 chapters)
Eclipse 4 Plug-in Development by Example Beginner's Guide
Credits
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

Time for action – creating warning and error messages


In free-form text fields it's sometimes possible to input a value that doesn't make sense. For example, when asking someone for their e-mail address it might be necessary to validate it against some kind of regular expression like .+@.+ to provide a simplistic test. Perform the following steps:

  1. To test the default validation, run the Eclipse instance and go to the Clock preference page. Type some text in the numeric field. A warning message will be displayed as shown in the following screenshot:

  2. To add validation, create a new field called offset which allows valid values between -14 and +12. (By default, IntegerFieldEditor validates against the range 0 to MAX_INT.) Add the following to the createFieldEditors() method:

    IntegerFieldEditor offset = new IntegerFieldEditor("offset","Current offset from GMT", getFieldEditorParent());
    offset.setValidRange(-14, +12);
    addField(offset);
  3. Run the Eclipse instance, go to the Clock preference page and...