code: public int put(Iterable<? extends Widget> widgets, int startIndex) throws IndexOutOfBoundsException {
  		int index = startIndex;
  		for (Widget widget : widgets) {
  			put(widget, index);
  			++index;
  		}
  		return index;
  	}
docs: Adds all widgets from given iterable
  
  @param widgets    Iterable object containing widgets
  @param startIndex index at wich adding will start
  @return Index of last added element
  @throws IndexOutOfBoundsException when specified startIndex is negative or there is no more space