code: private void initializeForDesktop() {
  		logger.log(Level.FINE, "ZoomControl ->initializeForDesktop()");
  		StopPropagationHandler preventWeirdBehaviourHandler = new StopPropagationHandler();
  		addDomHandler(preventWeirdBehaviourHandler, MouseDownEvent.getType());
  		addDomHandler(preventWeirdBehaviourHandler, MouseUpEvent.getType());
  		addDomHandler(preventWeirdBehaviourHandler, ClickEvent.getType());
  		addDomHandler(preventWeirdBehaviourHandler, DoubleClickEvent.getType());
  
  		final ViewPort viewPort = mapPresenter.getViewPort();
  
  		// Zoom in button:
  		zoomInElement.addDomHandler(new ClickHandler() {
  
  			public void onClick(ClickEvent event) {
  				logger.log(Level.FINE, "ZoomControl -> zoomInElement onClick()");
  				int index = viewPort.getResolutionIndex(viewPort.getResolution());
  				if (index < viewPort.getResolutionCount() - 1) {
  					viewPort.registerAnimation(NavigationAnimationFactory.createZoomIn(mapPresenter));
  				}
  				event.stopPropagation();
  			}
  		}, ClickEvent.getType());
  
  		// Zoom out button:
  		zoomOutElement.addDomHandler(new ClickHandler() {
  
  			public void onClick(ClickEvent event) {
  				logger.log(Level.FINE, "ZoomControl -> zoomOutElement onClick()");
  				int index = viewPort.getResolutionIndex(viewPort.getResolution());
  				if (index > 0) {
  					viewPort.registerAnimation(NavigationAnimationFactory.createZoomOut(mapPresenter));
  				}
  				event.stopPropagation();
  			}
  		}, ClickEvent.getType());
  	}
docs: Initialize handlers for desktop browser.