@Override
  public boolean isAlwaysShowPlus() {
    final VirtualFile file = getVirtualFile();
    if (file == null || !file.isValid()) return false;
    VirtualFile[] children = file.getChildren();
    if (ArrayUtil.isEmpty(children)) return false;
    if (ContainerUtil.exists(children, child -> !child.isDirectory())) return true;
    ViewSettings settings = getSettings();
    return settings == null || !settings.isFlattenPackages();
  }
@Override
  public boolean isAlwaysShowPlus()