没有发现材料小部件颤动与代码

Question

我正在使用 VS Code 在 Flutter 中设置 TextField 小部件，但在 TextFormField 上出现此错误：

No Material widget found.
TextField widgets require a Material widget ancestor.
I/flutter ( 3827): In material design, most widgets are conceptually "printed" on a sheet of material. In Flutter's
I/flutter ( 3827): material library, that material is represented by the Material widget. It is the Material widget
I/flutter ( 3827): that renders ink splashes, for instance. Because of this, many material library widgets require that
I/flutter ( 3827): there be a Material widget in the tree above them.
I/flutter ( 3827): To introduce a Material widget, you can either directly include one, or use a widget that contains
I/flutter ( 3827): Material itself, such as a Card, Dialog, Drawer, or Scaffold.
I/flutter ( 3827): The specific widget that could not find a Material ancestor was:
I/flutter ( 3827):   TextField
I/flutter ( 3827): The ancestors of this widget were:
I/flutter ( 3827):   ...
I/flutter ( 3827):   TextFormField
I/flutter ( 3827):   Column
I/flutter ( 3827):   Padding
I/flutter ( 3827):   Padding
I/flutter ( 3827):   Container

而TextFormField的代码是：

TextFormField txtEmail(String title, IconData icon) {
        return TextFormField(
          controller: emailController,
          style: TextStyle(color: Colors.white70),
          decoration: InputDecoration(
              hintText: title,
              hintStyle: TextStyle(color: Colors.white70),
              icon: Icon(icon)),
        );
      }

实际上我在此调用 txtEmail：

Container textSection() {
    return Container(
      padding: EdgeInsets.symmetric(horizontal: 20.0),
      margin: EdgeInsets.only(top: 30.0),
      child: Column(
        children: <Widget>[
          txtEmail("Email", Icons.email),
          SizedBox(height: 30.0),
          txtPassword("Password", Icons.lock),
        ],
      ),
    );
  }

是什么原因？

Answer 1

我认为您需要一个 Material Widget 作为根对象（例如 MaterialApp）

void main() async {
  runApp(
    MaterialApp(
      debugShowCheckedModeBanner: false,
        home: Scaffold(
          body: MyApp(),
        ),
      ),
    );
  }

查看https://flutter.dev/ 获取教程。