import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: Text('新手礼包'),
),
body: Center(
child: NewUserGiftForm(),
),
),
);
}
}
class NewUserGiftForm extends StatefulWidget {
@override
_NewUserGiftFormState createState() => _NewUserGiftFormState();
}
class _NewUserGiftFormState extends State<NewUserGiftForm> {
final _formKey = GlobalKey<FormState>();
String _giftContent;
void _submit() {
if ((_formKey.currentState as FormState).validate()) {
(_formKey.currentState as FormState).save();
// 处理提交逻辑，例如保存数据到数据库或执行网络请求等
Scaffold.of(context).showSnackBar(SnackBar(content: Text('礼包内容：$_giftContent')));
}
}
@override
Widget build(BuildContext context) {
return Form(
key: _formKey,
child: Column(
children: <Widget>[
TextFormField(
decoration: InputDecoration(labelText: '礼包内容'),
validator: (value) {
if (value.isEmpty) {
return '礼包内容不能为空';
}
return null;
},
onSaved: (value) => _giftContent = value,
),
RaisedButton(
child: Text('提交'),
onPressed: _submit,
),
],
),
);
}
}这段代码展示了如何在Flutter中创建一个简单的表单，用户可以在其中输入新手礼包的内容，并通过一个RaisedButton来提交这些内容。如果输入的内容非空，则会显示一个包含输入内容的SnackBar。这个例子教会了如何使用Form、TextFormField和表单的验证以及保存机制。