Custom Swing Button

You can create a custom class that extends Canvas.  Here's a basic example.  This creates an oval button that changes from green to red when pressed,  you can include an image in the canvas and change the image on mousepress.  I'll see if I have an example somewhere

import java.awt.*;

/**
 * <strong>ButtonCanvasExample</strong> -- implementing
 * a simple custom button as a subclass of <code>Canvas</code>.
 *
 * <p>
 * Experiment:
 * <ul>
 *   <li>Click on both the regular button and on
 *       the green oval button.
 *   <li>Click slowly to see how each button shows
 *       its pressed state.
 * </ul>
 */
public class ButtonCanvasExample extends java.applet.Applet {

    Button myButton = new Button("a regular button");
    ButtonCanvas myCanvas = new ButtonCanvas(40, 20);
    TextArea eventLog = new TextArea();
    int actionCount = 0;

    /** Builds the applet's interface. */
    public void init() {
     Panel buttonPanel = new Panel();
     buttonPanel.add(myButton);
     buttonPanel.add(myCanvas);
     
     setLayout(new BorderLayout());
     add("North", buttonPanel);
     add("Center", eventLog);
    }

    /** Displays action event information. */
    public boolean action(Event e, Object what) {
     ++actionCount;
     eventLog.appendText("Action event #" + actionCount
                   + "  target's class = "
                   + e.target.getClass().getName() + "\n");
     return true;
    }

}


/**
 * A Canvas subclass that acts as simple button.
 * It changes color to indicate whether it is pressed or not.
 * It generates an action event for each mouseUp event it
 * receives.
 */
class ButtonCanvas extends Canvas {

    int bWidth;
    int bHeight;
    boolean buttonPressed = false;

    /**
     * Creates an oval ButtonCanvas that fits inside
     * a rectangle with the specified width and height.
     */
    public ButtonCanvas(int width, int height) {
     bWidth = width;
     bHeight = height;
    }

    /**
     * Sets the Canvas's size;
     * otherwise it would default to (0, 0).
     */
    public Dimension preferredSize() {
     return new Dimension(bWidth, bHeight);
    }

    /**
     * Sets the Canvas's minimum size to equal its preferred size.
     */
    public Dimension minimumSize() {
     return preferredSize();
    }

    /**
     * Changes the appearance of the ButtonCanvas to reflect
     * the mouseDown as a button press.
     * Returns true to indicate that the event has been
     * completely handled.
     */
    public boolean mouseDown(Event e, int x, int y) {
     buttonPressed = true;
     repaint();
     return true;
    }

    /**
     * Changes the appearance of the ButtonCanvas to reflect
     * the mouseUp as a button release.
     * Generates an action event and posts it to this object.
     * Returns true to indicate that the event has been
     * completely handled.
     */
    public boolean mouseUp(Event e, int x, int y) {
     buttonPressed = false;
     repaint();
     postEvent(new Event(this, Event.ACTION_EVENT, null));
     return true;
    }

    /** Draws an oval button in two different colors. */
    public void paint(Graphics g) {

     if (buttonPressed) {
         g.setColor(Color.red);
     } else {
         g.setColor(Color.green);
     }

     g.fillOval(0, 0, bWidth, bHeight);
    }

}

hi,
Thx a lot for the reply. The example was really very good.
But, I want a button and not an image. Actually I require this for a big Swing based application. That is why I dont want an image to be loaded over the button. It is an application and not an applet program. What i know is, I think you need to call the paint() method and its other associated methods.

Actually, If u would have seen the buttons in IBM Visual Age for Java, or the buttons during Oracle Installation. Something like that I wnat. pls Help me.

hi,
Thx a lot for the reply. The example was really very good.
But, I want a button and not an image. Actually I require this for a big Swing based application. That is why I dont want an image to be loaded over the button. It is an application and not an applet program. What i know is, I think you need to call the paint() method and its other associated methods.

Actually, If u would have seen the buttons in IBM Visual Age for Java, or the buttons during Oracle Installation. Something like that I wnat. pls Help me.

No comment has been added lately, so it's time to clean up this TA.

I will leave a recommendation in the Cleanup topic area that this question is:

- points to keithlong

Please leave any comments here within the
next seven days.

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER !

girionis
Cleanup Volunteer