flutter - Future Builder 不是在 build

Question

我正在尝试使用分配给用户 firestore 文档中“isVerified”字段的 bool 值登录用户。

换句话说，如果'isVerified'为真则继续，否则返回验证页面。

我放入了 debugPrint 语句来帮助我捕获错误，并且 Future Builder 似乎没有通过构建器上下文。我已经阅读了有关 future build 者的其他文档，但我找不到哪里出错了，如果有什么我可以澄清的，请告诉我。谢谢

使用 Future Builder 实现异步

FutureBuilder (
        future: getVerified(),
        builder: (context, snapshot) { <--------- Nothing past this line is running
          debugPrint('>> Home: FutureBuilder: checkpoint'); // does not print to console
          if (snapshot.hasData && !snapshot.hasError) {
            debugPrint('>> Home: FutureBuilder: Snapshot has data and no error');
          }
          return const Text('');
        }
      );

future

Future<bool> getVerified() async {
  debugPrint('>> Home: getVerified Started');
  User? user = auth.currentUser;
  await FirebaseFirestore.instance
      .collection('users')
      .doc(user!.uid)
      .get()
      .then((value) {
    bool isVerified = value.data()!['isVerified'];
    debugPrint('>> Home: getVerified $isVerified'); // this variable is currently true or false
    return isVerified; // this will return Instance of '_Future'
  });
  return false;
}

Answer 1

你不需要改变 FutureBuilder 这很好。我重新编写了您的 getVerified() 函数。

你能试试吗

Future<bool> getVerified() async {
  debugPrint('>> Home: getVerified Started');
  bool isVerified = false; // set your response to false

  // get your user
  final user = FirebaseAuth.instance.currentUser;

  // check the data from firestore if the user is not null
  if (user != null) {
    final docSnapShot = await FirebaseFirestore.instance
        .collection('users')
        .doc(user.uid)
        .get();

    if (docSnapShot.exists) {
      isVerified = docSnapShot.data()!['isVerified'];
    }
  }

  debugPrint(
      '>> Home: getVerified $isVerified'); // this variable is currently true or false
  return isVerified; // this will return Instance of '_Future'
}