Flutter退出App的方法一般有两种
①SystemNavigator.pop 推荐
onTap: () async {
await pop();
},
static Future<void> pop() async { await SystemChannels.platform.invokeMethod(‘SystemNavigator.pop‘); }
别忘了引用
import ‘package:flutter/services.dart‘;
原文参考： https://docs.flutter.io/flutter/services/SystemNavigator/pop.html
②exit(0)
onPressed: ()=> exit(0),
原文参考： https://docs.flutter.io/flutter/dart-io/exit.html