这应该适用于一个项目

body: new StreamBuilder(
    stream: Firestore.instance.collection("collection").snapshots(),
    builder: (context, snapshot) {
      if (!snapshot.hasData) {
        return Text(
          'No Data...',
        );
      } else { 
          <DocumentSnapshot> items = snapshot.data.documents;

          return new Lost_Card(
          headImageAssetPath : items[0]["url"]
          );
      }

如果你想从许多文档中创建列表生成器，可以这样使用它

return new ListView.builder(
            itemCount: snapshot.data.documents.length,
            itemBuilder: (context, index) {
              DocumentSnapshot ds = snapshot.data.documents[index];
              return new Lost_Card(
                headImageAssetPath : ds["url"];

);

在Flutter 2中使用StreamBuilder访问文档

StreamBuilder<QuerySnapshot>(
    stream: FirebaseFirestore.instance.collection('products').snapshots(),
    builder: (context, snapshot) {
        if (snapshot.hasData) {
        return ListView.builder(
            itemCount: snapshot.data!.docs.length,
            itemBuilder: (context, index) {
                DocumentSnapshot doc = snapshot.data!.docs[index];
                return Text(doc['name']);
            });
        } else {
        return Text("No data");
        }
    },
)

根据Firebase FireStore中2021年的新变更，您可以使用StreamBuilder从集合中检索数据，如下所示

final _mFirestore = FirebaseFirestore.instance;

return StreamBuilder<QuerySnapshot>(
  stream:
      _mFirestore.collection(kFirebaseCollectionName).snapshots(),
  builder: (context, snapshots) {
    if (!snapshots.hasData) {
      return Center(
        child: Text('Data not available',),
      );
    }
    final messages = snapshots.data.docs;
    List<Text> textWidgets = [];

    messages.forEach((element) {
      final messageText = element['text'];
      final messageSender = element['sender'];

      final textWidget = Text('$messageText, $messageSender');
      textWidgets.add(messageBubbleWidget);
    });
  },
);

Card buildItem(DocumentSnapshot doc) {
return Card(
  child: Padding(
    padding: const EdgeInsets.all(8.0),
    child: Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: <Widget>[
        Text(
          'name: ${doc.data['name']}',
          style: TextStyle(fontSize: 24),
        ),
        Text(
          'todo: ${doc.data['todo']}',
          style: TextStyle(fontSize: 20),
        ),
        Text(
          'Age: ${doc.data['age']}',
          style: TextStyle(fontSize: 10),
        ),
        SizedBox(
          height: 12,
        ),
          ],
        )
      ],
    ),
  ),
);  }

对于其他面临同样问题的人来说，卡片和流构建器将提供一个解决方案。小部件在声明之前包含卡片，并在主体中包含下一部分：

body: ListView(
        padding: EdgeInsets.all(8),
        children: <Widget>[
          Form(
            key: _formKey,
            child: buildTextFormField(),
          ),
          StreamBuilder<QuerySnapshot>(
            stream: db
                .collection('CRUD')
                .snapshots(),
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return Column(
                    children: snapshot.data.documents
                        .map((doc) => buildItem(doc))
                        .toList());
              } else {
                return SizedBox();
              }
            },
          )
        ],
      ),

针对2022年、Flutter 2.10、cloud_firestore的更新：^3.1.11.您可以使用StreamBuilder从集合中检索数据

Stream collectionStream = FirebaseFirestore.instance.collection('users').snapshots();

      StreamBuilder<QuerySnapshot>(
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                final messages = snapshot.data!.docs;
                List<Text> messageWidgets = [];

                for (var element in messages) {
                  final messageText = element['text'];
                  final messageSender = element['sender'];

                  final messageWidget =
                      Text('$messageText from $messageSender');
                  messageWidgets.add(messageWidget);
                }
                return Column(
                  children: messageWidgets,
                );
              }
              return const Text('Error');
            },
            stream:collectionStream),

StreamBuilder<List<UData>>(
              stream: AdminData().getDrivers,
              builder: (context, snapshot) {
                return ListView(
                  children: snapshot.data.map((document) {
                    return hadCard(
                      widget: Row(
                        mainAxisAlignment: MainAxisAlignment.spaceAround,
                        children: [
                          hadText(title: document.name),
                          hadText(title: document.phone),
                          hadText(title: document.Driver),
                        ],
                      ),
                    );
                  }).toList(),
                );
              }),

使用null safety更新2023

多年来，许多事情发生了变化，我想更新与最新的可能的工作答案。

适用于多个文档的StreamBuilder

final Stream<QuerySnapshot> _usersStream =
      FirebaseFirestore.instance.collection('users').snapshots();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: StreamBuilder<QuerySnapshot>(
          stream: _usersStream,
          builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
            if (snapshot.hasError) {
              return const Text('Something went wrong');
            }
            if (snapshot.connectionState == ConnectionState.waiting) {
              return const Text("Loading");
            }
            return ListView(
                children: snapshot.data!.docs.map((DocumentSnapshot document) {
              Map<String, dynamic> data =
                  document.data()! as Map<String, dynamic>;
              return ListTile(
                title: Text(data['fullName']), // 👈 Your valid data here
              );
            }).toList());
          },
        ),
      ),
    );
  }

用于单个文档的StreamBuilder

class _UserInformationState extends State<UserInformation> {
  final _usersStream = FirebaseFirestore.instance
      .collection('users')
      .doc(FirebaseAuth.instance.currentUser!.uid) // 👈 Your document id change accordingly
      .snapshots();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: StreamBuilder<DocumentSnapshot<Map<String, dynamic>>>(
          stream: _usersStream,
          builder:
              (BuildContext context, AsyncSnapshot<DocumentSnapshot> snapshot) {
            if (snapshot.hasError) {
              return const Text('Something went wrong');
            }
            if (snapshot.connectionState == ConnectionState.waiting) {
              return const Text("Loading");
            }
            Map<String, dynamic> data =
                snapshot.data!.data()! as Map<String, dynamic>;
            return Text(data['fullName']);
          },
        ),
      ),
    );
  }
}