最近在做一个埋点的sdk,由于埋点是分批上传的,不是每次都上传,所以会有个进程保活的机制,这也是自研推送的实现技术之一:如何保证Android进程的存活。
对于Android来说,保活主要有以下一些方法:
- 开启前台Service(效果好,推荐)
- Service中循环播放一段无声音频(效果较好,但耗电量高,谨慎使用)
- 双进程守护(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(不推荐)
- 广播锁屏、自定义锁屏(不推荐)
- 第三方推送SDK唤醒(效果好,缺点是第三方接入)
下面是具体的实现方案:
1.监听锁屏广播,开启1个像素的Activity
最早见到这种方案的时候是2015年,有个FM的app为了向投资人展示月活,在Android应用中开启一个1像素的Activity。
由于Activity的级别是比较高的,所以开启1个像素的Activity的方式就可以保证进程是不容易被杀掉的。
具体来说,定义一个1像素的Activity,在该Activity中动态注册自定义的广播。
class OnePixelActivity : AppCompatActivity() { private lateinit var br: BroadcastReceiver override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) //设定一像素的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里注册广播接受者 接受到广播结束掉一像素 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 { //销毁的时候解锁广播 unregisterReceiver(br) } catch (e: IllegalArgumentException) { } super.onDestroy() } /** * 检查屏幕是否点亮 */ private fun checkScreenOn() { val pm = this@OnePixelActivity.getSystemService(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, 双进程守护
双进程守护,在Android 5.0前是有效的,5.0之后就不行了。首先,我们定义定义一个本地服务,在该服务中播放无声音乐,并绑定远程服务
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 { //播放无声音乐 if (mediaPlayer == null) { mediaPlayer = MediaPlayer.create(this,R.raw.novioce) //声音设置为0 mediaPlayer?.setVolume(0f,0f) mediaPlayer?.isLooping = true//循环播放 play() } //启用前台服务,提升优先级 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) } //绑定守护进程 try { val intent3 = Intent(this,RemoteService::class.java) this.bindService(intent3,connection,Context.BIND_ABOVE_CLIENT) } catch (e: Exception) { } //隐藏服务通知 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 && !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) this@LocalService.startService(remoteService) val intent = Intent(this@LocalService,RemoteService::class.java) this@LocalService.bindService(intent,this,Context.BIND_ABOVE_CLIENT) } override fun onServiceConnected(name: ComponentName,service: IBinder) { try { if (mBilder != null && 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() } } }
然后再定义一个远程服务,绑定本地服务。
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,startId: Int): Int { try { this.bindService(Intent(this@RemoteService,LocalService::class.java),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,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) this@RemoteService.startForeground(13691,notification) } } } private val connection = object : ServiceConnection { override fun onServiceDisconnected(name: ComponentName) { val remoteService = Intent(this@RemoteService,LocalService::class.java) this@RemoteService.startService(remoteService) this@RemoteService.bindService(Intent(this@RemoteService,service: IBinder) {} } } /** * 通知栏点击广播接受者 */ 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从5.0增加的支持一种特殊的任务调度机制,可以用它来实现进程保活,不过在Android8.0系统中,此种方法也失效。
首先,我们定义一个JobService,开启本地服务和远程服务。
@SuppressWarnings(value = ["unchecked","deprecation"]) @RequiresApi(Build.VERSION_CODES.LOLLIPOP) class JobHandlerService : JobService() { private var mJobScheduler: JobScheduler? = null override fun onStartCommand(intent: Intent?,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) //执行的最小延迟时间 builder.setOverrideDeadline(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS) //执行的最长延时时间 builder.setMinimumLatency(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS) builder.setBackoffCriteria(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS,JobInfo.BACKOFF_POLICY_LINEAR)//线性重试方案 } else { builder.setPeriodic(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS) } builder.setrequiredNetworkType(JobInfo.NETWORK_TYPE_ANY) builder.setRequiresCharging(true) // 当插入充电器,执行该任务 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,intent) startForeground(13691,notification) } } //启动本地服务 val localIntent = Intent(context,LocalService::class.java) //启动守护进程 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,"$packageName:remote")) { startService(this) } return false } override fun onStopJob(jobParameters: JobParameters): Boolean { if (!isServiceRunning(applicationContext,"$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优先级
在onStartCommand()方法中开启一个通知,提高进程的优先级。注意:从Android 8.0(API级别26)开始,所有通知必须要分配一个渠道,对于每个渠道,可以单独设置视觉和听觉行为。然后用户可以在设置中修改这些设置,根据应用程序来决定哪些通知可以显示或者隐藏。
首先,定义一个通知工具类,此工具栏兼容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,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,intent: Intent): Notification.Builder { //PendingIntent.FLAG_UPDATE_CURRENT 这个类型才能传值 val pendingIntent = PendingIntent.getBroadcast(context,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,intent: Intent): NotificationCompat.Builder { val pendingIntent = PendingIntent.getBroadcast(context,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) .setContentIntent(pendingIntent) } }
5,Workmanager方式
Workmanager是Android JetPac中的一个API,借助Workmanager,我们可以用它来实现应用饿保活。使用前,我们需要依赖Workmanager库,如下:
implementation "android.arch.work:work-runtime:1.0.0-alpha06"
Worker是一个抽象类,用来指定需要执行的具体任务。
public class KeepLiveWork extends Worker { private static final String TAG = "KeepLiveWork"; @NonNull @Override public WorkerResult doWork() { Log.d(TAG,"keep-> doWork: startKeepService"); //启动job服务 startJobService(); //启动相互绑定的服务 startKeepService(); return WorkerResult.SUCCESS; } }
然后,启动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); }
关于WorkManager,可以通过下面的文章来详细了解:WorkManager浅谈