How can I recognize when a cell is click ?

Hello, I have a question.

I would like to know how can I recognize when an empty cell is click and the event dialog edit is open in a CALENDAR.

I tried with

		calendar
				.addClickHandler(new com.smartgwt.client.widgets.events.ClickHandler() {

					@Override
					public void onClick(ClickEvent event) {
					}
				});
		
		

		calendar.addEventClickHandler(new EventClickHandler() {

			@Override
			public void onEventClick(CalendarEventClick event) {

			}
		});

But they do not work.

Thanks!