我遇到了一个问题,当我尝试使用开关小部件时,它在警报框内无法正常工作,因为它不会切换到第二状态,每当我尝试轻弹它时它就会弹跳。我想知道这是因为开关本身有问题还是我如何在框中显示它?谢谢!
import 'package:flutter/material.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key key}) : super(key: key);
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',theme: ThemeData(),home: SwitchDemo(),);
}
}
class SwitchDemo extends StatefulWidget {
const SwitchDemo({Key key}) : super(key: key);
@override
State<StatefulWidget> createState() => new _TabsPageState();
}
class _TabsPageState extends State<SwitchDemo> {
bool isInstructionView;
@override
void initState() {
super.initState();
isInstructionView = Global.shared.isInstructionView;
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("add data"),),body: Container(
child: TextButton(
child: Text('Open Alert Box'),onpressed: () => {
showDialog(
context: context,builder: (BuildContext context) {
return Padding(
padding: EdgeInsets.symmetric(
horizontal: MediaQuery.of(context).size.width / 20,vertical:
MediaQuery.of(context).size.height / 20,child: AlertDialog(
content: Container(
child: Switch(
value: isInstructionView,onChanged: (bool isOn) {
if (isInstructionView == false) {
} else if (isInstructionView == true) {}
setState(() {
isInstructionView = isOn;
Global.shared.isInstructionView = isOn;
isOn = !isOn;
});
},activeColor: Colors.blue,inactiveTrackColor: Colors.grey,inactiveThumbColor: Colors.grey,);
})
}),));
}
}
class Global {
static final shared = Global();
bool isInstructionView = false;
}