Android P实现静默安装的方法示例(官方Demo)

Android9.0无法通过以下两种方式实现静默安装：

1.runtime执行shell cmd
2.PackageInstall 反射机制

但是Google已经给我们推荐了相关的APIDemos，所以建议大家多看看源码~

在frameworks/base/core/java/android/content/pm/PackageInstaller.java有段关于该类的介绍：

1. The ApiDemos project contains examples of using this API:

2. <code>ApiDemos/src/com/example/android/apis/content/InstallApk*.java</code>.

/**
* Offers the ability to install, upgrade, and remove applications on the
* device. This includes support for apps packaged either as a single
* "monolithic" APK, or apps packaged as multiple "split" APKs.
* <p>
* An app is delivered for installation through a
* {@link PackageInstaller.Session}, which any app can create. Once the session
* is created, the installer can stream one or more APKs into place until it
* decides to either commit or destroy the session. Committing may require user
* intervention to complete the installation.
* <p>
* Sessions can install brand new apps, upgrade existing apps, or add new splits
* into an existing app.
* <p>
* Apps packaged as multiple split APKs always consist of a single "base" APK
* (with a {@code null} split name) and zero or more "split" APKs (with unique
* split names). Any subset of these APKs can be installed together, as long as
* the following constraints are met:
* <ul>
* <li>All APKs must have the exact same package name, version code, and signing
* certificates.
* <li>All APKs must have unique split names.
* <li>All installations must contain a single base APK.
* </ul>
* <p>
* ###########此处告诉开发者如何调用API安装apk##############
* The ApiDemos project contains examples of using this API:
* <code>ApiDemos/src/com/example/android/apis/content/InstallApk*.java</code>.  
*/
public class PackageInstaller

翻阅源码，InstallApk*.java相关的一共两个demo
InstallApkSessionApi.java //静默安装
InstallApk.java //普通安装，调用系统install intent进行安装

下面是InstallApkSessionApi.java的具体demo

package com.example.android.apis.content;

// Need the following import to get access to the app resources, since this
// class is in a sub-package.
import com.example.android.apis.R;

import android.app.Activity;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageInstaller;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
* Demonstration of package installation and uninstallation using the package installer Session
* API.
*
* @see InstallApk for a demo of the original (non-Session) API.
*/
public class InstallApkSessionApi extends Activity {
 private static final String PACKAGE_INSTALLED_ACTION =
     "com.example.android.apis.content.SESSION_API_PACKAGE_INSTALLED";

@Override
 protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);

setContentView(R.layout.install_apk_session_api);

// Watch for button clicks.
   Button button = (Button) findViewById(R.id.install);
   button.setOnClickListener(new 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("HelloActivity.apk", session);

// Create an install status receiver.
         Context context = InstallApkSessionApi.this;
         Intent intent = new Intent(context, InstallApkSessionApi.class);
         intent.setAction(PACKAGE_INSTALLED_ACTION);

//此处也可以使用getBoradcast或者getService回调通知
         PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);
         IntentSender statusReceiver = pendingIntent.getIntentSender();

// Commit the session (this will start the installation workflow).
         session.commit(statusReceiver);
       } catch (IOException e) {
         throw new RuntimeException("Couldn't install package", 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[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().
 @Override
 protected void onNewIntent(Intent 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, "Install succeeded!", 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 failed! " + status + ", " + message,
             Toast.LENGTH_SHORT).show();
         break;
       default:
         Toast.makeText(this, "Unrecognized status received from installer: " + status,
             Toast.LENGTH_SHORT).show();
     }
   }
 }
}

另外，权限要求：

需要系统签名
permission

<uses-permission android:name="android.permission.INSTALL_PACKAGES" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

来源：https://www.jianshu.com/p/44360624db68