code: private void obtainShowDividersOnScroll(@StyleRes final int themeResourceId) {
          TypedArray typedArray = getContext().getTheme().obtainStyledAttributes(themeResourceId,
                  new int[]{R.attr.materialDialogShowDividersOnScroll});
          showDividersOnScroll(typedArray.getBoolean(0, true));
      }
docs: Obtains, whether the dividers, which are located above and below the dialog's scrollable
  areas, should be shown when scrolling, or not, from a specific theme.
  
  @param themeResourceId
  The resource id of the theme, the boolean value should be obtained from, as an {@link
  Integer} value