/** 异步加载头像位图到ImageLoader内存缓存 */
  private static void asyncLoadAvatarBitmapToCache(UserInfoProvider.UserInfo userInfo) {
    if (userInfo == null || !isImageUriValid(userInfo.getAvatar())) {
      return;
    }

    String url = HeadImageView.getAvatarCacheKey(userInfo.getAvatar());
    ImageLoader.getInstance()
        .loadImage(
            url,
            new ImageSize(
                HeadImageView.DEFAULT_AVATAR_THUMB_SIZE, HeadImageView.DEFAULT_AVATAR_THUMB_SIZE),
            avatarLoadOption,
            null);
  }
  /** 从ImageLoader内存缓存中取出头像位图 */
  private static Bitmap getMemoryCachedAvatarBitmap(UserInfoProvider.UserInfo userInfo) {
    if (userInfo == null || !isImageUriValid(userInfo.getAvatar())) {
      return null;
    }

    String key = HeadImageView.getAvatarCacheKey(userInfo.getAvatar());

    // DiskCacheUtils.findInCache(uri, ImageLoader.getInstance().getDiskCache() 查询磁盘缓存示例
    List<Bitmap> bitmaps =
        MemoryCacheUtils.findCachedBitmapsForImageUri(
            key, ImageLoader.getInstance().getMemoryCache());
    if (bitmaps.size() > 0) {
      return bitmaps.get(0);
    }

    return null;
  }