Flutter：TextUI的hintText在屏幕UI中未更新

如何解决Flutter：TextUI的hintText在屏幕UI中未更新

Using builTextField() method to create textField,passing different controller.
TextEditingController phoneController;
TextEditingController otpController;
builTextField(phoneController),builTextField(otpController),

hintText分别使用phoneController.text和otpController.text填充各自的textField。

类似地，

using buildRaisedButton() method to create Button,passing differetnt callback.
buildRaisedButton('Register',registrationCallback),buildRaisedButton('Verify',verifyOTPCallback),buildRaisedButton('Reset',resetCallback),

在按钮上单击“重置”，要清除两个文本字段的hitText

resetCallback(){
    print('cleared ....');
    setState(() {
      phoneController.clear();
      otpController.clear();
    });
  }

看起来controller.clear正在将conroller.text值重置为empty（''），但是由于hintText的值选择为conroller.text，因此也应该在屏幕上将其更新为“空”。但不幸的是，尽管将代码包装在setState（）中，但它仍未反映在UI中

buildTextField（）

Widget buildTextField(TextEditingController controller,) {
    return Container(
      height: 40.0,width: 200.0,decoration: BoxDecoration(
        color: Colors.blueAccent,borderRadius: BorderRadius.circular(32),),child: TextField(
        keyboardType: TextInputType.number,style: kPhoneAuthTextFields,decoration: InputDecoration(
          hintStyle: kPhoneAuthTextFields,hintText:controller.text,suffixIcon: Icon(Icons.phone_android,size: 20,color: Colors.white,border: InputBorder.none,contentPadding: EdgeInsets.only(top: 5.0,left: 30.0),onChanged: (value) {
          controller.text = value;
        },);
  }

buildRaisedButton（）

Widget buildRaisedButton(String label,Function callback){
    return Container(
      height: 40.0,width: 100.0,child: RaisedButton(
        child:Text(
          label,style: kPhoneLoginTextStyle,color: Colors.blue,//padding: EdgeInsets.all(8.0),shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(40.0)),onPressed: callback,);
  }

任何帮助，感谢...在此先感谢...

解决方法

您可以在下面复制粘贴运行完整代码
您可以在UniqueKey()中提供buildTextField
代码段

Widget buildTextField(TextEditingController controller,) {
    return Container(
      key: UniqueKey(),

工作演示

完整代码

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',theme: ThemeData(
        primarySwatch: Colors.blue,visualDensity: VisualDensity.adaptivePlatformDensity,),home: MyHomePage(title: 'Flutter Demo Home Page'),);
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key,this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  TextEditingController phoneController = TextEditingController();
  TextEditingController otpController = TextEditingController();

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  Widget buildTextField(
    TextEditingController controller,height: 40.0,width: 200.0,decoration: BoxDecoration(
        color: Colors.blueAccent,borderRadius: BorderRadius.circular(32),child: TextField(
        keyboardType: TextInputType.number,//style: kPhoneAuthTextFields,decoration: InputDecoration(
          hintStyle: TextStyle(color: Colors.orange),hintText: controller.text,suffixIcon: Icon(
            Icons.phone_android,size: 20,color: Colors.white,border: InputBorder.none,contentPadding: EdgeInsets.only(top: 5.0,left: 30.0),onChanged: (value) {
          controller.text = value;
        },);
  }

  Widget buildRaisedButton(String label,Function callback) {
    return Container(
      height: 40.0,width: 100.0,child: RaisedButton(
        child: Text(
          label,//style: kPhoneLoginTextStyle,color: Colors.blue,//padding: EdgeInsets.all(8.0),shape:
            RoundedRectangleBorder(borderRadius: BorderRadius.circular(40.0)),onPressed: callback,);
  }

  resetCallback() {
    print('cleared ....');
    setState(() {
      phoneController.clear();
      otpController.clear();
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,children: <Widget>[
            buildTextField(phoneController),buildTextField(otpController),buildRaisedButton('Reset',resetCallback),Text(
              'You have pushed the button this many times:',Text(
              '$_counter',style: Theme.of(context).textTheme.headline4,],floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,tooltip: 'Increment',child: Icon(Icons.add),);
  }
}