code: private int obtainTheme() {
          TypedArray typedArray =
                  getContext().getTheme().obtainStyledAttributes(new int[]{R.attr.toolbarTheme});
          return typedArray.getResourceId(0, 0);
      }
docs: Obtains the resource id of the theme, which should be applied on the toolbar.
  
  @return The resource id of the theme as an {@link Integer} value