Android 8.0以上系統應用如何保活

 對於Android來說，保活主要有以下一些方法：

• 開啟前台Service（效果好，推薦）
• Service中循環播放一段無聲音頻（效果較好，但耗電量高，謹慎使用）
• 雙進程守護（Android 5.0前有效）
• JobScheduler（Android 5.0后引入，8.0后失效）
• 1 像素activity保活方案（不推薦）
• 廣播鎖屏、自定義鎖屏（不推薦）
• 第三方推送SDK喚醒（效果好，缺點是第三方接入）

下面是具體的實現方案：

1.監聽鎖屏廣播，開啟1個像素的Activity

最早見到這種方案的時候是2015年，有個FM的app為了向投資人展示月活，在Android應用中開啟一個1像素的Activity。

由於Activity的級別是比較高的，所以開啟1個像素的Activity的方式就可以保證進程是不容易被殺掉的。

具體來說，定義一個1像素的Activity，在該Activity中動態注冊自定義的廣播。

class OnePixelActivity : AppCompatActivity() { private lateinit var br: BroadcastReceiver override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) //設定一像素的activity val window = window window.setGravity(Gravity.LEFT or Gravity.TOP) val params = window.attributes params.x = 0 params.y = 0 params.height = 1 params.width = 1 window.attributes = params //在一像素activity里注冊廣播接受者 接受到廣播結束掉一像素 br = object : BroadcastReceiver() { override fun onReceive(context: Context, intent: Intent) { finish() } } registerReceiver(br, IntentFilter("finish activity")) checkScreenOn() } override fun onResume() { super.onResume() checkScreenOn() } override fun onDestroy() { try { //銷毀的時候解鎖廣播 unregisterReceiver(br) } catch (e: IllegalArgumentException) { } super.onDestroy() } /** * 檢查屏幕是否點亮 */ private fun checkScreenOn() { val pm = [e-mail](Context.POWER_SERVICE) as PowerManager val isScreenOn = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT_WATCH) { pm.isInteractive } else { pm.isScreenOn } if (isScreenOn) { finish() } } } 

2， 雙進程守護

雙進程守護，在Android 5.0前是有效的，5.0之后就不行了。首先，我們定義定義一個本地服務，在該服務中播放無聲音樂，並綁定遠程服務

class LocalService : Service() { private var mediaPlayer: MediaPlayer? = null private var mBilder: MyBilder? = null override fun onCreate() { super.onCreate() if (mBilder == null) { mBilder = MyBilder() } } override fun onBind(intent: Intent): IBinder? { return mBilder } override fun onStartCommand(intent: Intent, flags: Int, startId: Int): Int { //播放無聲音樂 if (mediaPlayer == null) { mediaPlayer = MediaPlayer.create(this, R.raw.novioce) //聲音設置為0 mediaPlayer?.setVolume(0f, 0f) mediaPlayer?.isLooping = true//循環播放 play() } //啟用前台服務，提升優先級 if (KeepLive.foregroundNotification != null) { val intent2 = Intent(applicationContext, NotificationClickReceiver::class.java) intent2.action = NotificationClickReceiver.CLICK_NOTIFICATION val notification = NotificationUtils.createNotification(this, KeepLive.foregroundNotification!!.getTitle(), KeepLive.foregroundNotification!!.getDescription(), KeepLive.foregroundNotification!!.getIconRes(), intent2) startForeground(13691, notification) } //綁定守護進程 try { val intent3 = Intent(this, RemoteService::class.java) this.bindService(intent3, connection, Context.BIND_ABOVE_CLIENT) } catch (e: Exception) { } //隱藏服務通知 try { if (Build.VERSION.SDK_INT < 25) { startService(Intent(this, HideForegroundService::class.java)) } } catch (e: Exception) { } if (KeepLive.keepLiveService != null) { KeepLive.keepLiveService!!.onWorking() } return Service.START_STICKY } private fun play() { if (mediaPlayer != null &amp;&amp; !mediaPlayer!!.isPlaying) { mediaPlayer?.start() } } private inner class MyBilder : GuardAidl.Stub() { @Throws(RemoteException::class) override fun wakeUp(title: String, discription: String, iconRes: Int) { } } private val connection = object : ServiceConnection { override fun onServiceDisconnected(name: ComponentName) { val remoteService = Intent(this@LocalService, RemoteService::class.java) [e-mail](remoteService) val intent = Intent(this@LocalService, RemoteService::class.java) [e-mail](intent, this, Context.BIND_ABOVE_CLIENT) } override fun onServiceConnected(name: ComponentName, service: IBinder) { try { if (mBilder != null &amp;&amp; KeepLive.foregroundNotification != null) { val guardAidl = GuardAidl.Stub.asInterface(service) guardAidl.wakeUp(KeepLive.foregroundNotification?.getTitle(), KeepLive.foregroundNotification?.getDescription(), KeepLive.foregroundNotification!!.getIconRes()) } } catch (e: RemoteException) { e.printStackTrace() } } } override fun onDestroy() { super.onDestroy() unbindService(connection) if (KeepLive.keepLiveService != null) { KeepLive.keepLiveService?.onStop() } } } 

然后再定義一個遠程服務，綁定本地服務。

class RemoteService : Service() { private var mBilder: MyBilder? = null override fun onCreate() { super.onCreate() if (mBilder == null) { mBilder = MyBilder() } } override fun onBind(intent: Intent): IBinder? { return mBilder } override fun onStartCommand(intent: Intent, flags: Int, startId: Int): Int { try { this.bindService(Intent(this@RemoteService, LocalService::class.java), connection, Context.BIND_ABOVE_CLIENT) } catch (e: Exception) { } return Service.START_STICKY } override fun onDestroy() { super.onDestroy() unbindService(connection) } private inner class MyBilder : GuardAidl.Stub() { @Throws(RemoteException::class) override fun wakeUp(title: String, discription: String, iconRes: Int) { if (Build.VERSION.SDK_INT < 25) { val intent = Intent(applicationContext, NotificationClickReceiver::class.java) intent.action = NotificationClickReceiver.CLICK_NOTIFICATION val notification = NotificationUtils.createNotification(this@RemoteService, title, discription, iconRes, intent) [e-mail](13691, notification) } } } private val connection = object : ServiceConnection { override fun onServiceDisconnected(name: ComponentName) { val remoteService = Intent(this@RemoteService, LocalService::class.java) [e-mail](remoteService) [e-mail](Intent(this@RemoteService, LocalService::class.java), this, Context.BIND_ABOVE_CLIENT) } override fun onServiceConnected(name: ComponentName, service: IBinder) {} } } /** * 通知欄點擊廣播接受者 */ class NotificationClickReceiver : BroadcastReceiver() { companion object { const val CLICK_NOTIFICATION = "CLICK_NOTIFICATION" } override fun onReceive(context: Context, intent: Intent) { if (intent.action == NotificationClickReceiver.CLICK_NOTIFICATION) { if (KeepLive.foregroundNotification != null) { if (KeepLive.foregroundNotification!!.getForegroundNotificationClickListener() != null) { KeepLive.foregroundNotification!!.getForegroundNotificationClickListener()?.foregroundNotificationClick(context, intent) } } } } } 

3，JobScheduler

JobScheduler是Android從5.0增加的支持一種特殊的任務調度機制，可以用它來實現進程保活，不過在Android8.0系統中，此種方法也失效。

首先，我們定義一個JobService，開啟本地服務和遠程服務。

@SuppressWarnings(value = ["unchecked", "deprecation"]) @RequiresApi(Build.VERSION_CODES.LOLLIPOP) class JobHandlerService : JobService() { private var mJobScheduler: JobScheduler? = null override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int { var startId = startId startService(this) if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { mJobScheduler = getSystemService(Context.JOB_SCHEDULER_SERVICE) as JobScheduler val builder = JobInfo.Builder(startId++, ComponentName(packageName, JobHandlerService::class.java.name)) if (Build.VERSION.SDK_INT >= 24) { builder.setMinimumLatency(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS) //執行的最小延遲時間 builder.setOverrideDeadline(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS) //執行的最長延時時間 builder.setMinimumLatency(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS) builder.setBackoffCriteria(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS, JobInfo.BACKOFF_POLICY_LINEAR)//線性重試方案 } else { builder.setPeriodic(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS) } builder.setRequiredNetworkType(JobInfo.NETWORK_TYPE_ANY) builder.setRequiresCharging(true) // 當插入充電器，執行該任務 mJobScheduler?.schedule(builder.build()) } return Service.START_STICKY } private fun startService(context: Context) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) { if (KeepLive.foregroundNotification != null) { val intent = Intent(applicationContext, NotificationClickReceiver::class.java) intent.action = NotificationClickReceiver.CLICK_NOTIFICATION val notification = NotificationUtils.createNotification(this, KeepLive.foregroundNotification!!.getTitle(), KeepLive.foregroundNotification!!.getDescription(), KeepLive.foregroundNotification!!.getIconRes(), intent) startForeground(13691, notification) } } //啟動本地服務 val localIntent = Intent(context, LocalService::class.java) //啟動守護進程 val guardIntent = Intent(context, RemoteService::class.java) startService(localIntent) startService(guardIntent) } override fun onStartJob(jobParameters: JobParameters): Boolean { if (!isServiceRunning(applicationContext, "com.xiyang51.keeplive.service.LocalService") || !isServiceRunning(applicationContext, "$packageName:remote")) { startService(this) } return false } override fun onStopJob(jobParameters: JobParameters): Boolean { if (!isServiceRunning(applicationContext, "com.xiyang51.keeplive.service.LocalService") || !isServiceRunning(applicationContext, "$packageName:remote")) { startService(this) } return false } private fun isServiceRunning(ctx: Context, className: String): Boolean { var isRunning = false val activityManager = ctx .getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager val servicesList = activityManager .getRunningServices(Integer.MAX_VALUE) val l = servicesList.iterator() while (l.hasNext()) { val si = l.next() if (className == si.service.className) { isRunning = true } } return isRunning } } 

4，提高Service優先級

在onStartCommand()方法中開啟一個通知，提高進程的優先級。注意：從Android 8.0（API級別26）開始，所有通知必須要分配一個渠道，對於每個渠道，可以單獨設置視覺和聽覺行為。然后用戶可以在設置中修改這些設置，根據應用程序來決定哪些通知可以顯示或者隱藏。

首先，定義一個通知工具類，此工具欄兼容Android 8.0。

class NotificationUtils(context: Context) : ContextWrapper(context) {

    private var manager: NotificationManager? = null
    private var id: String = context.packageName + "51"
    private var name: String = context.packageName
    private var context: Context = context
    private var channel: NotificationChannel? = null

    companion object {
        @SuppressLint("StaticFieldLeak")
        private var notificationUtils: NotificationUtils? = null

        fun createNotification(context: Context, title: String, content: String, icon: Int, intent: Intent): Notification? {
            if (notificationUtils == null) {
                notificationUtils = NotificationUtils(context)
            }
            var notification: Notification? = null
            notification = if (Build.VERSION.SDK_INT >= 26) {
                notificationUtils?.createNotificationChannel()
                notificationUtils?.getChannelNotification(title, content, icon, intent)?.build()
            } else {
                notificationUtils?.getNotification_25(title, content, icon, intent)?.build()
            }
            return notification
        }
    }

    @RequiresApi(api = Build.VERSION_CODES.O)
    fun createNotificationChannel() {
        if (channel == null) {
            channel = NotificationChannel(id, name, NotificationManager.IMPORTANCE_MIN)
            channel?.enableLights(false)
            channel?.enableVibration(false)
            channel?.vibrationPattern = longArrayOf(0)
            channel?.setSound(null, null)
            getManager().createNotificationChannel(channel)
        }
    }

    private fun getManager(): NotificationManager {
        if (manager == null) {
            manager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        }
        return manager!!
    }

    @RequiresApi(api = Build.VERSION_CODES.O)
    fun getChannelNotification(title: String, content: String, icon: Int, intent: Intent): Notification.Builder {
        //PendingIntent.FLAG_UPDATE_CURRENT 這個類型才能傳值
        val pendingIntent = PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
        return Notification.Builder(context, id)
                .setContentTitle(title)
                .setContentText(content)
                .setSmallIcon(icon)
                .setAutoCancel(true)
                .setContentIntent(pendingIntent)
    }

    fun getNotification_25(title: String, content: String, icon: Int, intent: Intent): NotificationCompat.Builder {
        val pendingIntent = PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
        return NotificationCompat.Builder(context, id)
                .setContentTitle(title)
                .setContentText(content)
                .setSmallIcon(icon)
                .setAutoCancel(true)
                .setVibrate(longArrayOf(0))
                .setSound(null)
                .setLights(0, 0, 0)
                .setContentIntent(pendingIntent)
    }
}

 

5，Workmanager方式

Workmanager是Android JetPac中的一個API，借助Workmanager，我們可以用它來實現應用餓保活。使用前，我們需要依賴Workmanager庫，如下：

implementation "android.arch.work:work-runtime:1.0.0-alpha06"

Worker是一個抽象類，用來指定需要執行的具體任務。

public class KeepLiveWork extends Worker {
    private static final String TAG = "KeepLiveWork";

    @NonNull
    @Override
    public WorkerResult doWork() {
        Log.d(TAG, "keep-> doWork: startKeepService");
        //啟動job服務
        startJobService();
        //啟動相互綁定的服務
        startKeepService();
        return WorkerResult.SUCCESS;
    }
}

 

然后，啟動keepWork方法，

    public void startKeepWork() {
        WorkManager.getInstance().cancelAllWorkByTag(TAG_KEEP_WORK);
        Log.d(TAG, "keep-> dowork startKeepWork");
        OneTimeWorkRequest oneTimeWorkRequest = new OneTimeWorkRequest.Builder(KeepLiveWork.class)
                .setBackoffCriteria(BackoffPolicy.LINEAR, 5, TimeUnit.SECONDS)
                .addTag(TAG_KEEP_WORK)
                .build();
        WorkManager.getInstance().enqueue(oneTimeWorkRequest);

    }