In my last blog I explained how I built a Dock bar using the Timing Framework and the Glass pane. This one is a continuation, where I explain briefly a slight improvement on the bouncing effect.

You can try the new version with Java Web Start: (again jdk 1.6+).

Here is the source code under GPL.

The improvement is to get the icons to bounce lower and lower after each cycle. I am pretty sure that I could have gone overboard and use some physics equations here. However, I followed the keep-it-simple principle.

Instead of having one Animator object that repeats itself 6 times - 3 bounces - I created 3 different animator object. Each one goes from 0 to a different height. Then I used the Triggers available in the Timing Framework for starting the next animator after the current one is finished. I was surprised of the simplicity of the API.

     TimingTrigger.addTrigger(animator[0], animator[1],
	                      TimingTriggerEvent.STOP);
     TimingTrigger.addTrigger(animator[1], animator[2],
			      TimingTriggerEvent.STOP);
     TimingTrigger.addTrigger(animator[2], animator[3],
                              TimingTriggerEvent.STOP);

The other improvement I added was that after the bouncing animation is completed, I get the bar to animated into the standby state, instead of what I was doing before, which was to make the glass pane not visible. In this way it has a more smooth transition.

    animator[3].addTarget(new TimingTarget() {
       public void begin() {}
       public void end() {
          glass.disolve();
       }
       public void repeat() {}
       public void timingEvent(float arg0) {}
    });

Here you can see the disolve method:

   public void disolve() {
      if ((disolver == null) || (!disolver.isRunning())) {
	for (int i = 0; i < iconsOnBar.size(); ++i) {
	   IconOnBar iconOnBar = iconsOnBar.get(i);
	   iconOnBar.setMouseLocation(MOUSE_OUT);
	}
	disolver = PropertySetter.createAnimator(500, glass,
						"progress", 0f, 1f);
	disolver.setAcceleration(0.3f);
	disolver.setDeceleration(0.2f);
	disolver.addTarget(new TimingTarget() {
           public void begin() {}
           public void end() {
              glass.setVisible(false);
	   }
           public void repeat() {}
           public void timingEvent(float t) {}
	});
	disolver.start();
     }
   }

We just make sure that there is no other disolver animation in the works, we update the state of all the icons to be "mouse out" and start the animation.