@Override
			public void handleEvent (Event e) {
				if (shell.getModified()) {
					MessageBox box = new MessageBox (shell, SWT.PRIMARY_MODAL | SWT.OK | SWT.CANCEL);
					box.setText (shell.getText ());
					box.setMessage ("You have unsaved changes, do you want to exit?");
					e.doit = box.open () == SWT.OK;
				}
			}