有時(shí)候使用某些api需要使用系統(tǒng)權(quán)限，如調(diào)用PackageInstaller的相關(guān)接口，需要android.permission.INSTALL_PACKAGES權(quán)限，該權(quán)限系統(tǒng)只會(huì)授權(quán)給系統(tǒng)應(yīng)用，此時(shí)可以考慮將我們的應(yīng)用升級(jí)為系統(tǒng)應(yīng)用，升級(jí)為系統(tǒng)應(yīng)用有兩種方法：

1、將apk放到/system/app目錄下，重啟手機(jī)即可，此方法比較粗暴，而且需要修改/system目錄的讀寫(xiě)權(quán)限，因此需要root，而且隨著Android系統(tǒng)版本對(duì)權(quán)限管理越來(lái)越嚴(yán)，root和修改讀寫(xiě)權(quán)限更繁瑣和復(fù)雜

2、添加sharedUserId='android.uid.system'配置，同時(shí)使用系統(tǒng)簽名對(duì)apk進(jìn)行重簽名，安裝后即有系統(tǒng)權(quán)限，此方法需要獲取到系統(tǒng)簽名，但通常廠商開(kāi)發(fā)的rom都不會(huì)公開(kāi)簽名，因此如果針對(duì)某些自己集成系統(tǒng)的需求，可以使用此方案。

下面針對(duì)第2種方案進(jìn)行講解。

1、首先需要在menifest文件中添加sharedUserId='android.uid.system'配置，如下

<manifest xmlns:android='http://schemas.android.com/apk/res/android' package='com.google.example' android:sharedUserId='android.uid.system'>

2、添加需要的使用的系統(tǒng)權(quán)限，如

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

3、使用系統(tǒng)簽名對(duì)apk進(jìn)行簽名，首先需要打未簽名的包，Android Studio環(huán)境下點(diǎn)擊右側(cè)Gradle按鈕，彈出目錄，打開(kāi)Tasks->build->assemble...，其中assemble開(kāi)頭的幾項(xiàng)即是打包任務(wù)，雙擊相應(yīng)項(xiàng)即可獲取相應(yīng)的包

接著要獲取系統(tǒng)簽名，找到系統(tǒng)簽名文件“platform.pk8”和“platform.x509.pem”，在系統(tǒng)源碼路徑下

簽名文件路徑：android/build/target/product/security/

準(zhǔn)備好簽名工具：“signapk.jar”

位置：android/prebuilts/sdk/tools/lib

將未簽名的apk、簽名文件和簽名工具放在同一路徑下，開(kāi)啟終端，cd到該目錄，運(yùn)行如下命令即可得到帶系統(tǒng)簽名的apk

java -jar signapk.jar platform.x509.pem platform.pk8 Demo.apk signedDemo.apk

以上的方法相對(duì)還是比較繁瑣，而且不便于調(diào)試，可以將系統(tǒng)簽名打入keystore，使用該keystore即可在Android Studio環(huán)境下生成帶系統(tǒng)簽名的apk

1、首先需要生成keystore文件，生成過(guò)程在此省略，可自行百度

2、下載keytool-importkeypair,https://github.com/getfatday/keytool-importkeypair/

3、該操作需要linux系統(tǒng)，并安裝jdk，win10環(huán)境下可以開(kāi)啟“基于Lunix的Windows子系統(tǒng)”，不需要去折騰安裝虛擬機(jī)或者系統(tǒng)。當(dāng)如，如果兄dei你已經(jīng)有Linux系統(tǒng)或者是mac，那么恭喜你，省了很多需要折騰的步驟

4、將keystore、platform.pk8、platform.x509.pem、keytool-importkeypair放在同一目錄下，開(kāi)啟終端，cd到此目錄，運(yùn)行如下命令即可將系統(tǒng)簽名打入keystore

/keytool-importkeypair -k ./demo.keystore -p password -pk8 platform.pk8 -cert platform.x509.pem -alias demoAlias

解釋：-P后接keystore密碼，-alias后接key alias

5、運(yùn)行結(jié)束即會(huì)在當(dāng)前目錄下生成帶有系統(tǒng)簽名的keystore，使用此keystore安裝Android Studio打包流程打包即可得到帶系統(tǒng)權(quán)限的apk

補(bǔ)充知識(shí)：Android 系統(tǒng)級(jí)應(yīng)用守護(hù)進(jìn)程

我就廢話不多說(shuō)了，還是直接看代碼吧！

--- a/frameworks/base/packages/SystemUI/src/com/android/systemui/SystemUIApplication.java+++ b/frameworks/base/packages/SystemUI/src/com/android/systemui/SystemUIApplication.java@@ -16,24 +16,51 @@package com.android.systemui;+import android.app.ActivityManager;+import android.app.ActivityManager.RunningAppProcessInfo;import android.app.Application;import android.app.Instrumentation;import android.content.BroadcastReceiver;import android.content.Context;+import android.content.ComponentName;import android.content.Intent;import android.content.IntentFilter;import android.content.res.Configuration;+import android.database.ContentObserver;+import android.net.Uri;+import android.os.Build;+import android.os.Handler;import android.os.Process;import android.os.PowerManager;import android.os.SystemClock;import android.os.SystemProperties;import android.os.UserHandle;import android.util.Log;-+import java.util.List;+import java.util.Calendar;import com.android.systemui.stackdivider.Divider;import java.util.HashMap;import java.util.Map;+import java.util.Objects;+import java.io.BufferedReader;+import java.io.File;+import java.io.FileReader;+import java.io.FileWriter;+import java.io.IOException;+import java.text.SimpleDateFormat;+import java.util.Date;+import java.util.Locale;++import java.io.FileInputStream;+import java.io.FileNotFoundException;+import java.io.FileOutputStream;+import java.io.InputStream;+import java.io.PrintWriter;+import java.math.BigInteger;+import java.security.MessageDigest;+import java.security.NoSuchAlgorithmException;+import java.util.Random;/** * Application class for SystemUI.@@ -42,6 +69,8 @@ public class SystemUIApplication extends Application { private static final String TAG = 'SystemUIService'; private static final boolean DEBUG = false;+ + private Context mContext; /** * The classes of the stuff to start.@@ -86,6 +115,8 @@ public class SystemUIApplication extends Application { // application theme in the manifest does only work for activities. Keep this in sync with // the theme set there. setTheme(R.style.systemui_theme);++mContext = getApplicationContext(); SystemUIFactory.createFromConfig(this);@@ -143,6 +174,7 @@ public class SystemUIApplication extends Application { private static final String SETTING_SYSTEM = 'tchip.provider.setting.system'; private static final String SETTING_SECURE = 'tchip.provider.setting.secure'; private static final String SETTING_GLOBAL = 'tchip.provider.setting.global';+ private static final String BROADCAST_SCREENSHOT = 'rk.android.screenshot.action'; private String valueContent = '0'; private MainReceiver mainReceiver; @@ -150,6 +182,10 @@ public class SystemUIApplication extends Application {android.util.Log.i('AZ', log); } + private void LDLog(String log) {+android.util.Log.i('LD', log);+ }+public class MainReceiver extends BroadcastReceiver {@Override@@ -225,6 +261,18 @@ public class SystemUIApplication extends Application {intentDown.putExtra('android.intent.extra.KEY_CONFIRM', false);intentDown.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);context.startActivity(intentDown);+ } else if (BROADCAST_SCREENSHOT.equals(action)) {+Intent intentScreenShot = new Intent('android.intent.action.SCREENSHOT');+intentScreenShot.putExtra('path', intentScreenShot.getExtras().getString('path'));+intentScreenShot.putExtra('name', intentScreenShot.getExtras().getString('name'));+context.sendBroadcast(intentScreenShot);+ } else if (BROADCAST_TIMETICK.equals(action)) {+//checkLaidianAppAlive();+try{+ mHandler.removeCallbacks(laidianAppR);+}catch(Exception e){+}+mHandler.postDelayed(laidianAppR, 1000); }} }@@ -326,4 +374,82 @@ public class SystemUIApplication extends Application { public SystemUI[] getServices() { return mServices; }+ + + Handler mHandler = new Handler();+ private int laidianAppCheckTime = 3000;+ Runnable laidianAppR = new Runnable(){++@Override+public void run() {+ checkAppAlive(pkgName', 'clsName');+ mHandler.postDelayed(laidianAppR, laidianAppCheckTime);+}+ + };++ private void checkAppAlive(String pkgName, String clsName){+long startTime = System.currentTimeMillis();+if(!isAppAlive(pkgName)){+ LDLog('checkAppAlive.start to start app... ');+ try{+ComponentName componentName = new ComponentName(pkgName, clsName);+Intent intent = new Intent();+intent.setComponent(componentName);+intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);+mContext.startActivity(intent);+ }catch(Exception e){++ }+}else{+ LDLog('checkAppAlive.app is running... ');+}+LDLog('checkAppAlive.used time : ' + (System.currentTimeMillis() - startTime));+ }+ + public boolean isAppAlive(String packageName){+//boolean isAlive = false;+//String command = 'ps | grep ' + packageName/* + ' | busybox awk ’{print $2}’'*/;+//String[] result = ExecCmd.getPackagePID(command);+//for(String str :result){+ // if(!'-1'.equals(str)){+ // isAlive = true;+ // }+//}+//return isAlive;++ // 獲取正在運(yùn)行的進(jìn)程+ /*ActivityManager activityManager = (ActivityManager) mContext.getSystemService(Context.ACTIVITY_SERVICE);+ List<RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();+ + for (RunningAppProcessInfo appProcess : appProcesses) {+ String[] pkgList = appProcess.pkgList;+ for (String pckName : pkgList) {+if(packageName.equals(pckName)){+ return true;+}+ + }+ }*/+ActivityManager am = (ActivityManager) mContext.getSystemService(Context.ACTIVITY_SERVICE);+List<ActivityManager.RecentTaskInfo> recentTasks = am.getRecentTasks(30, ActivityManager.RECENT_IGNORE_UNAVAILABLE+ | ActivityManager.RECENT_INCLUDE_PROFILES);++for (ActivityManager.RecentTaskInfo recentInfo : recentTasks){+ //if (recentInfo.origActivity != null) {+String pckName = recentInfo.baseIntent.getComponent().getPackageName();+LDLog('isAppAlive.packageName=' + pckName);+if(packageName.equals(pckName)){+ return true;+}+ //}+}+ return false;+ }+}

以上這篇Android普通應(yīng)用升級(jí)為系統(tǒng)應(yīng)用并獲取系統(tǒng)權(quán)限的操作就是小編分享給大家的全部?jī)?nèi)容了，希望能給大家一個(gè)參考，也希望大家多多支持好吧啦網(wǎng)。