@Override
		public void handleEvent(Event event) {
			/* 
			 * The following is done asynchronously to allow the Text's width
			 * to be changed before re-calculating its preferred height. 
			 */
			display.asyncExec(new Runnable() {
				@Override
				public void run() {
					if (text.isDisposed()) return;
					Point size = text.computeSize(text.getSize().x - trimWidth, SWT.DEFAULT);
					if (expandItem1.getHeight() != size.y) {
						expandItem1.setHeight(size.y);
					}
				}
			});
		}