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 – drawing a second hand


A clock with no hands and no numbers is just a circle.

Since arcs are drawn anticlockwise from 0 (on the right, or 3 p.m.) through 90 (12 p.m.), then 180 (9 p.m.), then 270 (6 p.m.), and finally back to 360 (3 p.m.), it is possible to calculate the arc's position for the second hand by using (15-s)*6%360.

  1. Go to the paintControl() method of the PaintListener inside ClockView.

  2. Add a variable seconds that is initialized to new Date().getSeconds().

  3. Get SWT.COLOR_BLUE via the display and store it in a local variable blue.

  4. Set the background color of the graphics context to blue.

  5. Draw an arc using the previous formula to draw the second hand.

    The code should look like the following:

    public void paintControl(PaintEvent e) {
      int seconds = new Date().getSeconds();
      int arc = (15-seconds) * 6 % 360;
      Color blue = e.display.getSystemColor(SWT.COLOR_BLUE);
      e.gc.setBackground(blue);
      e.gc.fillArc(e.x,e.y,e.width-1,e.height-1,arc-1,2);
    }
  6. Start Eclipse and show the...