hyzp_ybqx-Commit080：解决以下两个问题：

1、对长度小于等于2的区县名称（“高县”、“珙县”等）不进行去尾操作
2、在线升级测试OK。使用app_installer: 0.5.0插件，准备解决Android11允许“安装未知来源”后应用重启的问题，https://pub.dev/packages/app_installer。

lib/pages/MyMsics/05_updated/MyUpdatedNew.dart

@@ -6,12 +6,13 @@ import 'dart:io';
 import 'dart:isolate';
 import 'dart:ui';
 
+import 'package:app_installer/app_installer.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_downloader/flutter_downloader.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:hyzp_ybqx/components/dioFun.dart';
-import 'package:open_file/open_file.dart';
 import 'package:path_provider/path_provider.dart';
+import 'package:permission_handler/permission_handler.dart';
 import 'package:progress_dialog/progress_dialog.dart';
 
 import '../../../components/commonFun.dart';
@@ -314,7 +315,17 @@ class MyUpdatedNew {
 
   /// 安装apk
   Future<Null> _installApk() async {
-    await OpenFile.open(appPath + '/' + apkName);
+    // await OpenFile.open(appPath + '/' + apkName);
+    // app_installer: 0.5.0          # Flutter 2.1，修复 Android 11 上允许权限后应用重启的问题，https://pub.dev/packages/app_installer
+    Map<Permission, PermissionStatus> permissionStatuses = await [
+      Permission.storage,
+    ].request();
+
+    if (permissionStatuses[Permission.storage] == PermissionStatus.granted) {
+      await AppInstaller.installApk(appPath + '/' + apkName);
+    } else {
+      print('Permission request fail!');
+    }
   }
 
   /// 获取apk存储位置