By default, Panel doesnt 'sink' the onCLick event. That is, clicking on Panels doesnt actually result into a 'ClickEvent' and hence the handler isnt fired. To use click events with Panel (or for that matter any other Widget) you must first invoke sinkEvents() on it with the appropriate event bits.
For example:
SimplePanel p = new SimplePanel();
p.sinkEvents(Event.ONCLICK);
p.setTitle("Click me");
p.setSize("600px", "600px");
p.addHandler(new ClickHandler(){
@Override
public void onClick(ClickEvent event) {
Window.alert("SimplePanel clicked!");
}
}, ClickEvent.getType());
The above piece of code first 'enables' click events for the SimplePanel using p.sinkEvents(Event.ONCLICK);
and then goes on to add the standard ClickHandler onto it. Note that even though SimplePanel doesnt implement HasClickHandlers, you can always add a handler using the addHandler()
method.
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