code: private void addDividers() {
          for (Map.Entry<DividerLocation, Divider> entry : dividers.entrySet()) {
              if (entry.getKey() == DividerLocation.BOTTOM && bottomDivider == null &&
                      !scrollableArea.isScrollable(Area.BUTTON_BAR)) {
                  bottomDivider = entry.getValue();
              } else if (entry.getKey() == DividerLocation.TOP && topDivider == null &&
                      !scrollableArea.isScrollable(Area.CONTENT)) {
                  topDivider = entry.getValue();
              }
          }
      }
docs: Adds the dividers, which are contained by the dialog, to the root view.