通过TextFormField更新数据库Firestore中的数据 - Flutter

Question

如何使TextFormField中写入的数据更新已记录的数据

这是我的登录屏幕。这是注册页面的一部分。登录页面上的相同代码

String _email, _password, id;
final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
final db = Firestore.instance;

Expanded(
                        child: TextFormField(
                          autofocus: false,
                          // controller: _email,
                          // validator: Validator.validateEmail,
                          onSaved: (input) => _email = input,
                          decoration: InputDecoration(
                            border: InputBorder.none,
                            hintText: 'Enter your email',
                            hintStyle: TextStyle(color: Colors.grey),
                          ),
                        ),
                      ),
Expanded(
                        child: FlatButton(
                          shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(30.0),
                          ),
                          color: Colors.blue,
                          onPressed: () {},
                          child: Row(
                            children: <Widget>[
                              Padding(
                                padding: EdgeInsets.only(left: 20.0),
                                child: Text(
                                  'SIGN UP',
                                  style: TextStyle(color: Colors.white),
                                ),
                              ),
                              Expanded(
                                child: Container(),
                              ),
                              Transform.translate(
                                offset: Offset(10.0, 0.0),
                                child: Container(
                                  padding: EdgeInsets.all(1.0),
                                  child: FlatButton(
                                    shape: RoundedRectangleBorder(
                                      borderRadius: 
                                       BorderRadius.circular(28.0)
                                    ),
                                    color: Colors.white,
                                    child: Icon(
                                      Icons.arrow_forward,
                                      color: Colors.blue,
                                    ),
                                    onPressed: () async {
                                      // _emailSignUp(
                                      //   email:_email.text,
                                      //   password:_password.text,
                                      //   context: context
                                      // );

                                      createData();
                                      signUp();
                                      sharedPreferences = await 
                     SharedPreferences.getInstance();

                     sharedPreferences.setString("email", _email);
                                    },
                                  ),
                                ),
                              )
                            ],
                          ),
                        ),
                      )
 void createData() async {
    if (_formKey.currentState.validate()) {
      _formKey.currentState.save();
      DocumentReference ref = await db.collection('users').add({'email': '$_email', 'name': 'UserName', 'userPhotoURL': 'url'});
      setState(() => id = ref.documentID);
      print(ref.documentID);
    }
  }

AccountScreen。在这里，我想通过TextFormField更新数据用户。我想根据进来的用户确定需要更改哪些数据

class AccountScreen extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => AccountScreenState();
}

class AccountScreenState extends State<AccountScreen> {
  final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
  String countries;
  String selected;
  SharedPreferences sharedPreferences;
  String _name, _email;
  final db = Firestore.instance;

  @override
  void initState() {
    super.initState();
    getDataPreference();
  }

  getDataPreference() async {
    sharedPreferences = await SharedPreferences.getInstance();
    setState(() {
      _email = sharedPreferences.getString("email");
    });
  }

  // void updateData(DocumentSnapshot doc) async {
  //   await db.collection('users').document(doc.documentID).updateData({'email': '$_email', 'name': '$_name'});
  //   Navigator.of(context).pushReplacementNamed('/home_screen');
  // }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
          title: Text("Your account"), backgroundColor: Colors.blueGrey[900]),
      body: 
      Container(
        color: Colors.blueGrey[800],
        child: Form(
          key:_formKey,
        child: ListView(
          children: <Widget>[
            AccountImage(),
            ListTile(
                leading: Icon(Icons.account_box, color: Colors.white),
                title: TextFormField(
                  onSaved: (input) => _name = input,
                  style: TextStyle(color: Colors.white),
                  decoration: InputDecoration(
                      fillColor: Colors.white,
                      hintText: "Name",
                      hintStyle: TextStyle(color: Colors.white)),
                )),
            ListTile(
              leading: Icon(Icons.email, color: Colors.white),
              title: TextFormField(
                style: TextStyle(color: Colors.white),
                decoration: InputDecoration(
                    fillColor: Colors.white,
                    hintText: "Email",
                    hintStyle: TextStyle(color: Colors.white)),
                // keyboardType: TextInputType.emailAddress,
                initialValue: _email,
                onSaved: (input) => _email = input,
              ),
            ),
            ListTile(
              leading: Icon(Icons.language, color: Colors.white),
              title: DropDownCountries(),
            ),
            Container(
              padding: EdgeInsets.all(15.0),
              child: Material(
                color: Colors.blue[700],
                elevation: 3.0,
                child: MaterialButton(
                  height: 45.0,
                  child: Text("Save", style: TextStyle(color: Colors.white)),
                  onPressed: () {
                    // updateData();
                    Navigator.of(context).pushReplacementNamed('/home_screen');
                  }
                ),
              ),
            )
          ],
        ),
        )
      ),
    );
  }
}

Answer 1

你可以update这样的记录你可以从文件中获得documentID

Firestore.instance
        .collection('users')
        .document(userID)// use documentID here to update particular document
        .updateData({
      "email": emailController.text,//This is the data i.e going to be updated
      "City": cityController.text,//This is the data i.e going to be updated
      "Phone": phoneNumberController.text.toString(),//This is the data i.e going to be updated
});