自动更新功能的安卓App

• 自动更新主要下面4个步骤
• • 更新服务
  • 测试页面:MainPage.xaml
  • 测试

自动更新主要下面4个步骤

1、获取最新版本号
2、提示用户发现更新，等待用户确认更新
3、下载最新的apk包
4、安装apk包

更新服务

为简单示例：直接在android平台文件夹下新建静态类：UpgradeService.cs

包含：

• 检查更新
• 下载文件
• 安装apk包
  因为存在命名空间冲突问题，故需改下命名空间。

       public static class UpgradeService {readonly static HttpClient _client;static UpgradeService(){_client = new HttpClient();}public static async Task> CheckUpdatesAsync(string url){var result = new Dictionary();// 获取当前版本号var currentVersion = VersionTracking.CurrentVersion;var latestVersion = await _client.GetStringAsync(url);result.Add("CurrentVersion", currentVersion);result.Add("LatestVersion", latestVersion);return result;}public static void InstallNewVersion(){var file = $"{FileSystem.AppDataDirectory}/{"com.shez.addressbook-Signed.apk"}";var apkFile = new Java.IO.File(file);var intent = new Intent(Intent.ActionView);// 判断Android版本if (Build.VERSION.SdkInt >= BuildVersionCodes.N){//给临时读取权限intent.SetFlags(ActivityFlags.GrantReadUriPermission);var uri = FileProvider.GetUriForFile(Android.App.Application.Context, "com.shez.addressbook.fileprovider", apkFile);// 设置显式 MIME 数据类型intent.SetDataAndType(uri, "application/vnd.android.package-archive");}else{intent.SetDataAndType(Android.Net.Uri.FromFile(new Java.IO.File(file)), "application/vnd.android.package-archive");}//指定以新任务的方式启动Activityintent.AddFlags(ActivityFlags.NewTask);//激活一个新的ActivityAndroid.App.Application.Context.StartActivity(intent);}  public static async Task DownloadFileAsync(string url, Action action){var req = new HttpRequestMessage(new HttpMethod("GET"), url);var response = _client.SendAsync(req, HttpCompletionOption.ResponseHeadersRead).Result;var allLength = response.Content.Headers.ContentLength;var stream = await response.Content.ReadAsStreamAsync();var file = $"{FileSystem.AppDataDirectory}/{"com.shez.addressbook-Signed.apk"}";await using var fileStream = new FileStream(file, FileMode.Create);fileStream.Flush();await using (stream){var buffer = new byte[10240];var readLength = 0;int length;while ((length = await stream.ReadAsync(buffer, 0, buffer.Length)) != 0){readLength += length;action(readLength, allLength!.Value);// 写入到文件fileStream.Write(buffer, 0, length);}}}}

这里需要使用到 FileProvider，在Android 7之后出于安全考虑不再支持content://URL 或file:///URL这种文件访问方式，可参考FileProvider | Android Developers，我们先添加一下对应配置

在Platforms/Android/Resources下面新建xml文件夹，并添加provider_paths.xml文件

修改Platforms / Android下面的AndroidManifest.xml文件，在application下添加provider，再添加一个安卓安装的权限“REQUEST_INSTALL_PACKAGES”
通过WebApi请求获取发布的最新版本号。为简单示例,API读取配置文件获取。

其中com.shez.addressbook-Signed.apk为apk的文件名称。

测试页面:MainPage.xaml

cs代码：

为简单测试版本，Webapi接口直接读取配置文件版本。
直接文本显示百分比和下载字节数。

    public MainPage(){InitializeComponent();lblCurrentVersion.Text ="当前版本："+ VersionTracking.CurrentVersion;}private async void OnReLoginClicked(object sender, EventArgs e){await Shell.Current.GoToAsync("//LoginPage");}private async void OnExitClicked(object sender, EventArgs e){Environment.Exit(0);}/// 
/// 更新/// 
/// /// private async void OnUpdateClicked(object sender, EventArgs e){var result = await UpgradeService.CheckUpdatesAsync($"{ Operator.BaseUrl}/api/File/AddressBookVer");if (result["CurrentVersion"] != result["LatestVersion"]){var confirm = await Shell.Current.DisplayAlert("问题?", $"检测到新版本，是否升级,版本号为：" + result["LatestVersion"], "确定", "取消");if (confirm){await UpgradeService.DownloadFileAsync($"{Operator.BaseUrl}/api/File/AddressBook", DownloadProgressChanged);//https://你的域名/com.masa.mauidemo.apkUpgradeService.InstallNewVersion();UpdateBtn.IsEnabled = true;}}else{await Shell.Current.DisplayAlert("提示",$"当前版本已经是最新版,版本号为：" + result["LatestVersion"],"确定");}}private void DownloadProgressChanged(long readLength, long allLength){UpdateBtn.IsEnabled = false; var c = (int)(readLength * 100 / allLength);if (c > 0 && c % 5 == 0) //刷新进度为每5%更新一次，过快的刷新会导致页面显示数值与实际不一致{var BytesReceived = readLength / 1024; //当前已经下载的Kbvar TotalBytesToReceive = allLength / 1024; //文件总大小KblblPross.Text =$"正在下载中{c}% {BytesReceived}/{TotalBytesToReceive}...";if (c == 100){UpdateBtn.IsEnabled = true;}}}

测试

参考：https://blog.csdn.net/sunday866/article/details/126405322
并得到老师的指导，感谢！