code: public void waitForNotVisible(final long time) throws WidgetException {
  		try {
  			waitForCommand(new ITimerCallback() {
  
  				@Override
  				public boolean execute() throws WidgetException {
  					return !isVisible();
  				}
  
  				@Override
  				public String toString() {
  					return "Waiting for element with locator: " + locator + " to not be visible";
  				}
  			}, time);
  		} catch (Exception e) {
  			throw new WidgetException("Error while waiting for element to be not visible", locator, e);
  		}
  	}
docs: Waits for specific element at locator to be not visible within period of
  specified time
  
  @param time
  Milliseconds
  @throws WidgetException