@Override
			public void handleEvent (Event event) {
				switch (event.type) {
					case SWT.MouseEnter:
					case SWT.MouseMove:
						for (int i=0; i<rects.length; i++) {
							if (rects [i].contains (event.x, event.y)) {
								String text = "ToolTip " + i;
								if (!(text.equals (shell.getToolTipText ()))) {
									shell.setToolTipText ("ToolTip " + i);
								}
								return;
							}
						}
						shell.setToolTipText (null);
						break;
					}
			}