• 什么是使程序下载然后安装APK的概念 * 我已经安装程序，但当我安装程序，它不工作

download.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String getUrl = "https://apptrue.online/files/Truejek.apk";
                DownloadManager.Request request = new DownloadManager.Request(Uri.parse(getUrl));
                String title = URLUtil.guessFileName(getUrl, null, null);
                request.setTitle(title);
                request.setDescription("Sedang mendowload file");
                String cookie = CookieManager.getInstance().getCookie(getUrl);
                request.addRequestHeader("cookie", cookie);
                request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
                request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, title);

                DownloadManager downloadManager = (DownloadManager)getSystemService(DOWNLOAD_SERVICE);
                downloadManager.enqueue(request);
                Toast.makeText(UpdateActivity.this, "Download dimulai", Toast.LENGTH_SHORT).show();
                checkWriteExternalStoragePermission();
            }
        });

        install.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                PackageInstaller.Session session = null;
                try {
                    PackageInstaller packageInstaller = getPackageManager().getPackageInstaller();
                    PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
                            PackageInstaller.SessionParams.MODE_FULL_INSTALL);
                    int sessionId = packageInstaller.createSession(params);
                    session = packageInstaller.openSession(sessionId);
                    addApkToInstallSession(Environment.DIRECTORY_DOWNLOADS, session);
                    DevicePolicyManager dpm = (DevicePolicyManager) getApplicationContext().getSystemService(Context.DEVICE_POLICY_SERVICE);
                    dpm.clearDeviceOwnerApp(getApplicationContext().getPackageName());
                    checkWriteExternalStoragePermission();
                    Context context = UpdateActivity.this;
                    Intent intent = new Intent(context, UpdateActivity.class);
                    intent.setAction(PACKAGE_INSTALLED_ACTION);
                    PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_IMMUTABLE | PendingIntent.FLAG_UPDATE_CURRENT);
                    IntentSender statusReceiver = pendingIntent.getIntentSender();
                    // Commit the session (this will start the installation workflow).
                    session.commit(statusReceiver);
                } catch (IOException e) {
                    throw new RuntimeException("Tidak dapat menginstal paket", e);
                } catch (RuntimeException e) {
                    if (session != null) {
                        session.abandon();
                    }
                    throw e;
                }
            }
        });
    }
    private void addApkToInstallSession(String assetName, PackageInstaller.Session session)
            throws IOException {
        // It's recommended to pass the file size to openWrite(). Otherwise installation may fail
        // if the disk is almost full.
        try (OutputStream packageInSession = session.openWrite("package", 0, -1);
             InputStream is = getAssets().open(assetName)) {
            byte[] buffer = new byte[1638400];
            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().
    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        Bundle extras = intent.getExtras();
        if (PACKAGE_INSTALLED_ACTION.equals(intent.getAction())) {
            int status = extras.getInt(PackageInstaller.EXTRA_STATUS);
            String message = extras.getString(PackageInstaller.EXTRA_STATUS_MESSAGE);
            switch (status) {
                case PackageInstaller.STATUS_PENDING_USER_ACTION:
                    // This test app isn't privileged, so the user has to confirm the install.
                    Intent confirmIntent = (Intent) extras.get(Intent.EXTRA_INTENT);
                    startActivity(confirmIntent);
                    break;
                case PackageInstaller.STATUS_SUCCESS:
                    Toast.makeText(this, "Berhasil di install!", Toast.LENGTH_SHORT).show();
                    break;
                case PackageInstaller.STATUS_FAILURE:
                case PackageInstaller.STATUS_FAILURE_ABORTED:
                case PackageInstaller.STATUS_FAILURE_BLOCKED:
                case PackageInstaller.STATUS_FAILURE_CONFLICT:
                case PackageInstaller.STATUS_FAILURE_INCOMPATIBLE:
                case PackageInstaller.STATUS_FAILURE_INVALID:
                case PackageInstaller.STATUS_FAILURE_STORAGE:
                    Toast.makeText(this, "Install gagal! " + status + ", " + message,
                            Toast.LENGTH_SHORT).show();
                    break;
                default:
                    Toast.makeText(this, "Status tidak dikenal diterima dari penginstal: " + status,
                            Toast.LENGTH_SHORT).show();
            }
        }
    }

        private void checkWriteExternalStoragePermission () {

            if (ActivityCompat.checkSelfPermission(UpdateActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {

            } else {
                //  If we don't have permission than requesting  the permission
                requestWriteExternalStoragePermission();
            }
        }

        private void requestWriteExternalStoragePermission () {
            if (ActivityCompat.checkSelfPermission(UpdateActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(UpdateActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, MY_PERMISSION_REQUEST_WRITE_EXTERNAL_STORAGE);
            } else {
                ActivityCompat.requestPermissions(UpdateActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, MY_PERMISSION_REQUEST_WRITE_EXTERNAL_STORAGE);
            }
        }

        @Override
        public void onRequestPermissionsResult ( int requestCode, @NonNull String[] permissions,
        @NonNull int[] grantResults){
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
            if (requestCode == MY_PERMISSION_REQUEST_WRITE_EXTERNAL_STORAGE && grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            } else {
                Toast.makeText(UpdateActivity.this, "Izin Tidak Diberikan.", Toast.LENGTH_SHORT).show();
            }
        }

    }

它不适用于android 12和13那么使用安装程序包的错误在哪里

PackageInstaller packageInstaller = getPackageManager().getPackageInstaller();
                    PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
                            PackageInstaller.SessionParams.MODE_FULL_INSTALL);
                    int sessionId = packageInstaller.createSession(params);
                    session = packageInstaller.openSession(sessionId);
                    addApkToInstallSession(Environment.DIRECTORY_DOWNLOADS, session);
                    DevicePolicyManager dpm = (DevicePolicyManager) getApplicationContext().getSystemService(Context.DEVICE_POLICY_SERVICE);
                    dpm.clearDeviceOwnerApp(getApplicationContext().getPackageName());
                    checkWriteExternalStoragePermission();
                    Context context = UpdateActivity.this;
                    Intent intent = new Intent(context, UpdateActivity.class);
                    intent.setAction(PACKAGE_INSTALLED_ACTION);
                    PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_IMMUTABLE | PendingIntent.FLAG_UPDATE_CURRENT);
                    IntentSender statusReceiver = pendingIntent.getIntentSender();
                    // Commit the session (this will start the installation workflow).
                    session.commit(statusReceiver);

我开始通过本地webiste链接部署应用程序，而不是使用Google Play控制台来分发它，所以我想创建自己的安装程序概念