大概两个月前，我发现了这个问题。今天回来了，一点头绪也没有。据我所知，我的设置没有任何改变，所以很明显，无论过去的我想到什么，对现在的我来说都不够强大。我终于设法让一些东西重新工作了，所以在这里记录它，以便将来的我和其他可能从另一次尝试中受益的人。

这一尝试代表了原始Android Java安装APK - Session API示例的直接Xamarin c#翻译。它可能需要一些额外的工作，但这至少是一个开始。我让它运行在Android 9设备上，尽管我的项目针对的是Android 11。

InstallApkSessionApi.cs

namespace LauncherDemo.Droid
{
    using System;
    using System.IO;

    using Android.App;
    using Android.Content;
    using Android.Content.PM;
    using Android.OS;
    using Android.Widget;

    [Activity(Label = "InstallApkSessionApi", LaunchMode = LaunchMode.SingleTop)]
    public class InstallApkSessionApi : Activity
    {
        private static readonly string PACKAGE_INSTALLED_ACTION =
                "com.example.android.apis.content.SESSION_API_PACKAGE_INSTALLED";

        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);
            this.SetContentView(Resource.Layout.install_apk_session_api);

            // Watch for button clicks.
            Button button = this.FindViewById<Button>(Resource.Id.install);
            button.Click += this.Button_Click;
        }

        private void Button_Click(object sender, EventArgs e)
        {
            PackageInstaller.Session session = null;
            try
            {
                PackageInstaller packageInstaller = this.PackageManager.PackageInstaller;
                PackageInstaller.SessionParams @params = new PackageInstaller.SessionParams(
                        PackageInstallMode.FullInstall);
                int sessionId = packageInstaller.CreateSession(@params);
                session = packageInstaller.OpenSession(sessionId);
                this.AddApkToInstallSession("HelloActivity.apk", session);

                // Create an install status receiver.
                Context context = this;
                Intent intent = new Intent(context, typeof(InstallApkSessionApi));
                intent.SetAction(PACKAGE_INSTALLED_ACTION);
                PendingIntent pendingIntent = PendingIntent.GetActivity(context, 0, intent, 0);
                IntentSender statusReceiver = pendingIntent.IntentSender;

                // Commit the session (this will start the installation workflow).
                session.Commit(statusReceiver);
            }
            catch (IOException ex)
            {
                throw new InvalidOperationException("Couldn't install package", ex);
            }
            catch
            {
                if (session != null)
                {
                    session.Abandon();
                }

                throw;
            }
        }

        
        private void AddApkToInstallSession(string assetName, PackageInstaller.Session session)
        {
            // It's recommended to pass the file size to openWrite(). Otherwise installation may fail
            // if the disk is almost full.
            using Stream packageInSession = session.OpenWrite("package", 0, -1);
            using Stream @is = this.Assets.Open(assetName);
            byte[] buffer = new byte[16384];
            int n;
            while ((n = @is.Read(buffer)) > 0)
            {
                packageInSession.Write(buffer, 0, n);
            }
        }

        // Note: this Activity must run in singleTop launchMode for it to be able to receive the intent
        // in onNewIntent().
        protected override void OnNewIntent(Intent intent)
        {
            Bundle extras = intent.Extras;
            if (PACKAGE_INSTALLED_ACTION.Equals(intent.Action))
            {
                PackageInstallStatus status = (PackageInstallStatus)extras.GetInt(PackageInstaller.ExtraStatus);
                string message = extras.GetString(PackageInstaller.ExtraStatusMessage);
                switch (status)
                {
                    case PackageInstallStatus.PendingUserAction:
                        // This test app isn't privileged, so the user has to confirm the install.
                        Intent confirmIntent = (Intent) extras.Get(Intent.ExtraIntent);
                        this.StartActivity(confirmIntent);
                        break;
                    case PackageInstallStatus.Success:
                        Toast.MakeText(this, "Install succeeded!", ToastLength.Short).Show();
                        break;
                    case PackageInstallStatus.Failure:
                    case PackageInstallStatus.FailureAborted:
                    case PackageInstallStatus.FailureBlocked:
                    case PackageInstallStatus.FailureConflict:
                    case PackageInstallStatus.FailureIncompatible:
                    case PackageInstallStatus.FailureInvalid:
                    case PackageInstallStatus.FailureStorage:
                        Toast.MakeText(this, "Install failed! " + status + ", " + message,
                                ToastLength.Short).Show();
                        break;
                    default:
                        Toast.MakeText(this, "Unrecognized status received from installer: " + status,
                                ToastLength.Short).Show();
                        break;
                }
            }
        }
    }
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.companyname.launcherdemo" android:installLocation="auto">
    <uses-sdk android:minSdkVersion="21" android:targetSdkVersion="30" />
    <application android:label="LauncherDemo.Android" android:theme="@style/MainTheme" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
</manifest>

What I particularly like about this approach is that it does not require any special work in the manifest - no broadcast receivers, file providers, etc. Granted, this takes as its source some APK in the app's assets, whereas a more useful system will probably use some given APK path. I imagine that will introduce a certain level of additional complexity. In addition, I never ran into any issues here (at least as far as I could tell) with the Xamarin GC closing streams before Android was done with them. Nor did I have any issues with the APK not being parsed. I made sure to use a signed APK (the one generated by Visual Studio when deploying to the device worked just fine), and again I did not run into any file access permission issues simply due to using an APK from the app's assets in this example.

这里的一些其他答案提供的一件事是使侧面加载许可授予更加简化的想法。Yabaze Cool的回答提供了如下特色:

Intent unKnownSourceIntent = new Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES). setdata (Uri.parse(字符串。格式(“包:% s activity.getPackageName ()))); 如果(Build.VERSION。SDK_INT >= Build.VERSION_CODES.O) { if (!activity.getPackageManager(). canrequestpackageinstaller ()) { startActivityForResult (unKnownSourceIntent Constant.UNKNOWN_RESOURCE_INTENT_REQUEST_CODE); .．.

当我测试我的翻译时，我卸载了启动器演示程序和它安装的应用程序。没有向canrequestpackageinstalled提供检查，导致我不得不手动按下一个额外的设置按钮，将我带到与上面的ACTION_MANAGE_UNKNOWN_APP_SOURCES意图相同的对话框。因此，添加这个逻辑可以帮助在一定程度上简化用户的安装过程。

首先在AndroidManifest.xml中添加以下行:

<uses-permission android:name="android.permission.INSTALL_PACKAGES"
    tools:ignore="ProtectedPermissions" />

然后使用以下代码安装apk:

File sdCard = Environment.getExternalStorageDirectory();
            String fileStr = sdCard.getAbsolutePath() + "/MyApp";// + "app-release.apk";
            File file = new File(fileStr, "TaghvimShamsi.apk");
            Intent promptInstall = new Intent(Intent.ACTION_VIEW).setDataAndType(Uri.fromFile(file),
                    "application/vnd.android.package-archive");
            startActivity(promptInstall);

File file = new File(dir, "App.apk");
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive");
startActivity(intent);

我也遇到过同样的问题，在尝试了几次之后，结果是这样的。我不知道为什么，但是分别设置数据和类型破坏了我的意图。

我只是想分享一个事实，我的apk文件保存到我的应用程序“数据”目录，我需要更改apk文件的权限，使其成为世界可读的，以便允许它以这种方式安装，否则系统会抛出“解析错误:解析包存在问题”;所以使用@Horaceman的解决方案，使:

File file = new File(dir, "App.apk");
file.setReadable(true, false);
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive");
startActivity(intent);

试试这个 -在舱单上填写:

uses-permission android:name="android.permission.INSTALL_PACKAGES"
        tools:ignore="ProtectedPermissions"

编写代码:

File sdCard = Environment.getExternalStorageDirectory();
String fileStr = sdCard.getAbsolutePath() + "/Download";// + "app-release.apk";
File file = new File(fileStr, "app-release.apk");
Intent promptInstall = new Intent(Intent.ACTION_VIEW).setDataAndType(Uri.fromFile(file),
                        "application/vnd.android.package-archive");

startActivity(promptInstall);

在Android Oreo及以上版本中，我们必须采用不同的方法以编程方式安装apk。

 private void installApkProgramatically() {


    try {
        File path = activity.getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS);

        File file = new File(path, filename);

        Uri uri;

        if (file.exists()) {

            Intent unKnownSourceIntent = new Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES).setData(Uri.parse(String.format("package:%s", activity.getPackageName())));

            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {

                if (!activity.getPackageManager().canRequestPackageInstalls()) {
                    startActivityForResult(unKnownSourceIntent, Constant.UNKNOWN_RESOURCE_INTENT_REQUEST_CODE);
                } else {
                    Uri fileUri = FileProvider.getUriForFile(activity.getBaseContext(), activity.getApplicationContext().getPackageName() + ".provider", file);
                    Intent intent = new Intent(Intent.ACTION_VIEW, fileUri);
                    intent.putExtra(Intent.EXTRA_NOT_UNKNOWN_SOURCE, true);
                    intent.setDataAndType(fileUri, "application/vnd.android" + ".package-archive");
                    intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
                    intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
                    startActivity(intent);
                    alertDialog.dismiss();
                }

            } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {

                Intent intent1 = new Intent(Intent.ACTION_INSTALL_PACKAGE);
                uri = FileProvider.getUriForFile(activity.getApplicationContext(), BuildConfig.APPLICATION_ID + ".provider", file);
                activity.grantUriPermission("com.abcd.xyz", uri, Intent.FLAG_GRANT_READ_URI_PERMISSION);
                activity.grantUriPermission("com.abcd.xyz", uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
                intent1.setDataAndType(uri,
                        "application/*");
                intent1.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                intent1.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
                intent1.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
                startActivity(intent1);

            } else {
                Intent intent = new Intent(Intent.ACTION_VIEW);

                uri = Uri.fromFile(file);

                intent.setDataAndType(uri,
                        "application/vnd.android.package-archive");
                intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                startActivity(intent);
            }
        } else {

            Log.i(TAG, " file " + file.getPath() + " does not exist");
        }
    } catch (Exception e) {

        Log.i(TAG, "" + e.getMessage());

    }
}

在Oreo及以上版本中，我们需要未知资源安装权限。所以在活动结果中，你必须检查结果的权限

    @Override
public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    switch (requestCode) {

        case Constant.UNKNOWN_RESOURCE_INTENT_REQUEST_CODE:
            switch (resultCode) {
                case Activity.RESULT_OK:
                    installApkProgramatically();

                    break;
                case Activity.RESULT_CANCELED:
                    //unknown resouce installation cancelled

                    break;
            }
            break;
    }
}