小编Abd*_*ani的帖子

Flutter初学者在这里；我收到此错误：type 'Future<dynamic>' is not a subtype of type 'String'

从 Firebase 存储中获取下载 url 的函数

_getImageUrl(var fileName) async {
  print(fileName);
  final StorageReference ref = FirebaseStorage.instance.ref().child('categories/' + fileName);
  Uri downloadUrl = await ref.getDownloadURL();
  var url = downloadUrl.toString();
  return url;
}

我调用函数的地方

child:  Image(
  image:  AdvancedNetworkImage(
    _getImageUrl(menuItem['image'].toString()),
    timeoutDuration: Duration(minutes: 1),
    useDiskCache: true,
    cacheRule: CacheRule(maxAge: const Duration(days: 7)),
  ),
  height: mediaQuery.size.width * 0.22,
  width: mediaQuery.size.width * 0.22,
),