Full size Window gives blank page

Vaadin 6 / 7 / 8 Framework UI
1

hello , i’m having trouble on vaadin when i try to use full size portlet ,
here is my all code : http://pastebin.com/e931LAJT ,
when i set setFullSize on Window object , i got blank screen , how can i make full screen ?

I’ve tried
window.setFullSize();

and other container is :
AbsoluteLayout layout = new AbsoluteLayout();
layout.setFullSize();

But when i try this code , i got blank screen.
When i try to set size manually on AbsoluteLayout like ;

		final AbsoluteLayout layout = new AbsoluteLayout();
		
		layout.setWidth("800px");
		layout.setHeight("500px");

the code works fine , whats wrong?