'DocumentSnapshot'不是'String'类型的子对象

Question

我想从保存在FireStore中的url访问图像，但标题出现错误

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        theme: ThemeData(brightness: Brightness.dark),
        home: StreamBuilder(
            stream: Firestore.instance.collection('images').snapshots(),
            builder: (context, snapshot) {
              if (!snapshot.hasData) return CircularProgressIndicator();
              for (int i = 0; i < snapshot.data.documents.length; i++) {
                return ListWheelScrollView(children: <Widget>[
                  Image.network(snapshot.data.documents[i]),
                ]);
              }
            }));
  }
}

Answer 1

您要在Image.Network内部返回文档快照，要返回url，请使用方括号和“ url”内部：

Image.network(snapshot.data.documents[i]['url']),