code: public void setViewHandler(final int viewId, final ViewHandler<T> viewHandler) {
          if (viewHandler == null) {
              throw new IllegalArgumentException("'viewHandler' cannot be null.");
          }
          mViewHandlers.put(viewId, viewHandler);
      }
docs: Sets an {@link ViewHandler} for a given View id.
  
  @param viewId Designated View id.
  @param viewHandler A {@link ViewHandler} for the corresponding View.
  
  @throws IllegalArgumentException If evaluator is {@code null}.