public GenericDraweeHierarchyBuilder setOverlay(@Nullable Drawable overlay) {
    if (overlay == null) {
      mOverlays = null;
    } else {
      mOverlays = Arrays.asList(overlay);
    }
    return this;
  }
public GenericDraweeHierarchyBuilder setOverlay ( @ Nullable Drawable overlay ) { if ( overlay == null ) { mOverlays = null ; } else { mOverlays = Arrays . asList ( overlay ) ; } return this ; }
Sets a single overlay.

@param overlay overlay drawable
@return modified instance of this builder