无法从 firebase 中的文本字段表单中保存数据 [英] Unable to save the data from the textfields forms in the firebase
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问题描述
我正在尝试发送电子邮件并将用户输入数据从 Flutter 应用程序保存到 Firebase.
I was trying to send an email and save the user input data to the firebase from the flutter application.
我的代码是这样的:我已经创建了能够发送电子邮件的应用程序，但我一直无法将这些文本字段数据保存在 firebase 中.我已经在代码中实现了 Cloud Firestore，但出现了很多错误.
My code does: I have created the application which is capable to send email but I have got stuck to save those text fields data in the firebase. I have implemented the cloud firestore in the code but I am getting quite a few errors.
我的代码:
import 'package:flutter/material.dart';
import 'dart:async';
import 'package:flutter_email_sender/flutter_email_sender.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
// TODO: implement build
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Home(),
);
}
}
class Home extends StatefulWidget {
@override
State<StatefulWidget> createState() {
// TODO: implement createState
return _HomeState();
}
}
class _HomeState extends State<Home> {
var _emailFormKey = GlobalKey<FormState>();
TextEditingController emailController = new TextEditingController();
TextEditingController nameController = new TextEditingController();
TextEditingController numberController = new TextEditingController();
@override
Widget build(BuildContext context) {
// TODO: implement build
return Scaffold(
resizeToAvoidBottomPadding: false,
appBar: AppBar(
title: Text("Email sending App"),
),
body: Form(
key: _emailFormKey,
child: Column(
children: <Widget>[
Container(
margin: EdgeInsets.only(top: 50.0, left: 15.0, right: 15.0),
child: TextFormField(
controller: emailController,
validator: (value) {
if (value.isEmpty) {
return "please enter emailid";
}
},
decoration: InputDecoration(
labelText: "Enter email id",
border: OutlineInputBorder(
borderSide: BorderSide(
color: Colors.red,
width: 2.0,
))),
),
),
Container(
margin: EdgeInsets.only(top: 15.0, left: 15.0, right: 15.0),
child: TextFormField(
controller: numberController,
validator: (value) {
if (value.isEmpty) {
return "please enter number";
}
},
decoration: InputDecoration(
labelText: "Enter number",
border: OutlineInputBorder(
borderSide: BorderSide(
color: Colors.red,
width: 2.0,
))),
),
),
Container(
margin: EdgeInsets.only(top: 15.0, left: 15.0, right: 15.0),
child: TextFormField(
controller: nameController,
validator: (value) {
if (value.isEmpty) {
return "please Enter name";
}
},
decoration: InputDecoration(
labelText: "Enter name",
border: OutlineInputBorder(
borderSide: BorderSide(
color: Colors.red,
width: 2.0,
))),
),
),
Container(
margin: EdgeInsets.only(top: 15.0),
child: RaisedButton(
child: Text("Send"),
onPressed: () {
if (_emailFormKey.currentState.validate()) {
sendMessage();
//function to send data in the firebase
sendToServer();
}
}),
)
],
),
),
);
}
void sendMessage() {
var PhoneNumber;
String Name;
String Emailid;
Email email;
setState(() {
Emailid = emailController.text;
Name = nameController.text;
PhoneNumber = numberController.text;
String messageBody = '$Name
$PhoneNumber
$Emailid';
if (Name.isNotEmpty && Emailid.isNotEmpty && PhoneNumber.isNotEmpty) {
email = Email(
body: messageBody,
subject: 'Email subject',
recipients: ['onlineproductsking1@gmail.com'],
);
send(email);
sendToServer() {
if (_emailFormKey.currentState.validate()) {
//No error in validator
_emailFormKey.currentState.save();
Firestore.instance.runTransaction((Transaction transaction) async {
CollectionReference reference =
Firestore.instance.collection('contact');
await reference.add({
"Name": "$Name",
"Phone Number": "$PhoneNumber",
"Email Id": "$Emailid"
});
});
// } else {
// // validation error
// setState(() {
// // _validate = true;
// });
// }
}
}
}
});
debugPrint('name -> $Name, number -> $PhoneNumber, emailid -> $Emailid');
}
void send(Email email) async {
await FlutterEmailSender.send(email);
}
}
错误信息:
Compiler message:
^
lib/contact_form.dart:107:23: Error: The method 'sendToServer' isn't defined for the class '_HomeState'.
- '_HomeState' is from 'package:pdf/contact_form.dart' ('lib/contact_form.dart').
Try correcting the name to the name of an existing method, or defining a method named 'sendToServer'.
sendToServer();
^^^^^^^^^^^^
lib/contact_form.dart:138:48: Error: 'Transaction' isn't a type.
Firestore.instance.runTransaction((Transaction transaction) async {
^^^^^^^^^^^
lib/contact_form.dart:139:15: Error: 'CollectionReference' isn't a type.
CollectionReference reference =
^^^^^^^^^^^^^^^^^^^
lib/contact_form.dart:138:13: Error: The getter 'Firestore' isn't defined for the class '_HomeState'.
- '_HomeState' is from 'package:pdf/contact_form.dart' ('lib/contact_form.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'Firestore'.
Firestore.instance.runTransaction((Transaction transaction) async {
^^^^^^^^^
lib/contact_form.dart:140:19: Error: The getter 'Firestore' isn't defined for the class '_HomeState'.
- '_HomeState' is from 'package:pdf/contact_form.dart' ('lib/contact_form.dart').
Try correcting the name to the name of an existing getter, or defining a getter or field named 'Firestore'.
Firestore.instance.collection('books');
^^^^^^^^^
在 10,491 毫秒内重新启动应用程序.
Restarted application in 10,491ms.
请帮我解决这个问题，并指出我哪里出错了.
Please help me resolve this issue and mentioned where was I going wrong.
推荐答案
setState 接受一个没有参数且不返回数据的 voidCallback:
setState takes a voidCallback that have no arguments and doesn't return a data:
https://api.flutter.dev/flutter/widgets/State/setState.html
基本上:
setState(() {
});
基本上 () 是回调的无参数，而 {//... } 是回调内的代码.在您的回调中，您正在添加方法 sendToServer() 的实现，而您不能这样做..
Basically () is the no arguments of the callback and { //... } is the code inside the callback. In your case inside the callback, you are adding an implemenation of the method sendToServer() and you cant do that..
sendToServer() 是一个实例方法，它应该在 sendMessage() 或 setState 之外:
sendToServer() is an instance method and it should be outside sendMessage() or setState:
void sendMessage() {
var PhoneNumber;
String Name;
String Emailid;
Email email;
setState(() {
Emailid = emailController.text;
Name = nameController.text;
PhoneNumber = numberController.text;
String messageBody = '$Name
$PhoneNumber
$Emailid';
if (Name.isNotEmpty && Emailid.isNotEmpty && PhoneNumber.isNotEmpty) {
email = Email(
body: messageBody,
subject: 'Email subject',
recipients: ['onlineproductsking1@gmail.com'],
);
send(email);
}
});
debugPrint('name -> $Name, number -> $PhoneNumber, emailid -> $Emailid');
}
sendToServer() {
if (_emailFormKey.currentState.validate()) {
//No error in validator
_emailFormKey.currentState.save();
Firestore.instance.runTransaction((Transaction transaction) async {
CollectionReference reference =
Firestore.instance.collection('contact');
await reference.add({
"Name": "$Name",
"Phone Number": "$PhoneNumber",
"Email Id": "$Emailid"
});
});
}
}
关于其他错误，在您的 pubspec.yaml 文件中添加以下依赖项:
Regarding the other errors, in your pubspec.yaml file add the following dependency:
cloud_firestore: ^0.13.7
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