code: @Override
      protected void layoutChildren(final double x, final double y,
                                    final double w, final double h) {
          super.layoutChildren(x, y, w, h);
          final double height = getSkinnable().getHeight();
          linesWrapper.layoutLines(x, y, w, h, height,
              promptText == null ? 0 : snapPosition(promptText.getBaselineOffset() + promptText.getLayoutBounds().getHeight() * .36));
          errorContainer.layoutPane(x, height + linesWrapper.focusedLine.getHeight(), w, h);
  
          linesWrapper.updateLabelFloatLayout();
  
          if (invalid) {
              invalid = false;
              // update validation container
              errorContainer.invalid(w);
              // focus
              linesWrapper.invalid();
          }
      }
docs: *************************************************************************
  *
  Public API                                                              *
  *
  ************************************************************************