android - 前台服务 onTaskRemoved 发送广播 Intent 失败 android.os.DeadObjectException

Question

我正在开发https://github.com/mauron85/cordova-plugin-mauron85-background-geolocation-phonegapbuild

基本上它是 cordova 插件，它使用 LocationManager 将位置发送到 webview。

核心是作为 android.app.Service 实现的，它在前台启动，以减少被操作系统杀死的机会。

服务也有自己的进程(android:process=":remote")。 因此，服务将承受主要 Activity (线程)终止或用户关闭的应用程序的影响。即使被杀死，它也会通过在 onStartCommand 中设置标志 START_REDELIVER_INTENT 自动重新启动。

我的问题是，应用程序关闭(从任务列表中滑开)后，服务在几秒钟后崩溃。在日志中我看到:

W/BroadcastQueue(  562): Failure sending broadcast Intent { act=com.tenforwardconsulting.cordova.bgloc.STATIONARY_REGION_ACTION flg=0x10 (has extras) }
W/BroadcastQueue(  562): android.os.DeadObjectException
W/BroadcastQueue(  562):    at android.os.BinderProxy.transactNative(Native Method)
W/BroadcastQueue(  562):    at android.os.BinderProxy.transact(Binder.java:496)
W/BroadcastQueue(  562):    at android.app.ApplicationThreadProxy.scheduleRegisteredReceiver(ApplicationThreadNative.java:1093)
W/BroadcastQueue(  562):    at com.android.server.am.BroadcastQueue.performReceiveLocked(BroadcastQueue.java:431)
W/BroadcastQueue(  562):    at com.android.server.am.BroadcastQueue.deliverToRegisteredReceiverLocked(BroadcastQueue.java:521)
W/BroadcastQueue(  562):    at com.android.server.am.BroadcastQueue.processNextBroadcast(BroadcastQueue.java:729)
W/BroadcastQueue(  562):    at com.android.server.am.BroadcastQueue$BroadcastHandler.handleMessage(BroadcastQueue.java:149)
W/BroadcastQueue(  562):    at android.os.Handler.dispatchMessage(Handler.java:102)
W/BroadcastQueue(  562):    at android.os.Looper.loop(Looper.java:135)
W/BroadcastQueue(  562):    at android.os.HandlerThread.run(HandlerThread.java:61)
W/BroadcastQueue(  562):    at com.android.server.ServiceThread.run(ServiceThread.java:46)
W/ActivityManager(  562): Scheduling restart of crashed service com.xpressgo.courier.cordova/com.tenforwardconsulting.cordova.bgloc.DistanceFilterLocationService in 82050ms
W/ActivityManager(  562): Scheduling restart of crashed service com.xpressgo.courier.cordova/com.tenforwardconsulting.cordova.bgloc.FusedLocationService in 97188832ms

一段时间后(97188832ms)服务重新启动并正常运行。但为什么它一开始就崩溃了呢？当服务位于自己的线程中时，为什么发送广播失败？为什么自动重启后不会再崩溃？

Answer 1

我建议您在 DistanceFilterLocationService.java 的 onCreate() 中查看代码中的这些行(或由此引发的任何 Intent ):

...
// Stationary region PI
stationaryRegionPI  = PendingIntent.getBroadcast(this, 0, new Intent(STATIONARY_REGION_ACTION), PendingIntent.FLAG_CANCEL_CURRENT);
registerReceiver(stationaryRegionReceiver, new IntentFilter(STATIONARY_REGION_ACTION));
...

根据registerReceiver(BroadcastReceiver receiver, IntentFilter filter)的官方文档:

Registers a BroadcastReceiver to be run in the main activity thread. The receiver will be called with any broadcast Intent that matches filter, in the main application thread.

本质上，stationaryRegionReceiver 的 onReceive() 将在主 UI 线程上运行，如果您的应用关闭，该线程应该消失。 探索这个，registerReceiver (BroadcastReceiver receiver, IntentFilter filter, Handler handler)

您还可以使用这篇文章来测试部分代码在哪个线程中运行: How to check if current thread is not main thread .