我有一个警报应用程序，用户联系了我，该用户报告说他的警报有时会延迟。我尝试了不同的方法和理论，最后建议用户使用默认的 Android 警报作为备份。
通常警报会延迟大约一个小时，但上次我的警报是在 Android 的一个明确建议之后才开始的，该设备处于睡眠状态并被 Android 的警报唤醒，这也让我的“继续启动”。
编辑：由于我已经修改了一些类并且已经收到了来自新版本的日志，我正在更改下面的类和日志信息。
这是我正在使用的 CountedWakeLock 类 - 我创建了自己的 HandlerThread 来处理唤醒锁的延迟释放，以检查这是否会影响启动问题。它没有解决问题，但它在日志中产生了有趣的信息（如下）。
public class CountedWakeLock {
private static long TIMEOUT_DEFAULT = DateUtils.MINUTE_IN_MILLIS * 3;
private static WakeLock sWakeLock = null;
private static int sLockCount;
private static class TimeoutReleaseThread extends HandlerThread {
static TimeoutReleaseThread mInstance = null;
Handler mHandler;
private Runnable mReleaseRunnable;
public static TimeoutReleaseThread instance() {
if (mInstance == null) mInstance = new TimeoutReleaseThread();
return mInstance;
}
public TimeoutReleaseThread() {
super("TimeoutReleaseThread HandlerThread");
start();
mHandler = createHandler();
mReleaseRunnable = new Runnable() {
@Override
public void run() {
Utils.log("TimeoutReleaseThread release lock");
releaseLock();
}
};
}
private synchronized Handler createHandler() {
return new Handler(getLooper());
}
public synchronized void postRelease(long timeout) {
mHandler.removeCallbacks(mReleaseRunnable);
mHandler.postDelayed(mReleaseRunnable, timeout);
}
}
public synchronized static void acquireLock(Context context) {
acquireLock(context, TIMEOUT_DEFAULT);
}
public synchronized static void acquireLock(Context context, long timeout) {
if (sWakeLock == null) {
Utils.log("WakeLock creating");
PowerManager pm = (PowerManager) context.getApplicationContext()
.getSystemService(Context.POWER_SERVICE);
sWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
"AlarmReceiver lock");
sWakeLock.setReferenceCounted(false);
sLockCount = 0;
} else if (sWakeLock.isHeld())
Utils.log("WakeLock held already");
else
Utils.log("WakeLock not held");
Utils.log("WakeLock acquiring for " + timeout);
sLockCount++;
sWakeLock.acquire();
TimeoutReleaseThread.instance().postRelease(timeout);
}
public synchronized static void releaseLock() {
Utils.log("WakeLock releasing");
if (sWakeLock == null) {
Utils.log("WakeLock==null");
} else if (!sWakeLock.isHeld()) {
Utils.log("WakeLock not held");
sWakeLock = null;
sLockCount = 0;
} else {
sLockCount--;
if (sLockCount <= 0) {
Utils.log("WakeLock released");
sWakeLock.release();
sWakeLock = null;
if (sLockCount != 0) Utils.log("lockcount=" + sLockCount);
}
}
}
}
AlarmReceiver BroadcastReceiver - 它正在从 AlarmManager 接收意图
public void onReceive(Context context, Intent intent) {
Logger.initialize(context, "AlarmReceiver");
if (CALL_IS_ON) {
//set another alarm with AlarmManager to start after 5 seconds
//doesn't happen in this situation
} else {
Utils.log("sending START ALARM");
CountedWakeLock.acquireLock(context);
Intent i = new Intent();
i.setAction(StartAlarmReceiver.ACTION_START_ALARM);
i.putExtras(intent.getExtras());
context.sendOrderedBroadcast(i, null); //it is ordered, so eventual previous Alarm Activities etc. can be stopped
Utils.log("START ALARM send");
}
}
启动警报接收器。它实际上是在启动警报活动
public void onReceive(Context context, Intent intent) {
Logger.initialize(context, "StartAlarmReceiver");
Intent i = new Intent(context, AlarmOnScreen.class);
Bundle extras = intent.getExtras();
i.putExtras(extras);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
Utils.log("AlarmActivity started");
}
更新日志：
504. 27/3 5:0:0 - logger initialized again from AlarmReceiver
505. 27/3 5:0:0 - sending START ALARM
506. 27/3 5:0:0 - WakeLock creating
507. 27/3 5:0:0 - WakeLock acquiring for 180000
508. 27/3 5:0:0 - START ALARM send
509. 27/3 5:0:0 - logger initialized again from StartAlarmReceiver
510. 27/3 5:0:0 - AlarmActivity started
511. 27/3 5:0:0 - Main start
512. 27/3 5:0:1 - Main resume
513. 27/3 5:0:1 - Main pause
514. 27/3 5:0:5 - Main stop
515. 27/3 5:3:0 - TimeoutReleaseThread release lock
516. 27/3 5:3:0 - WakeLock releasing
517. 27/3 5:3:0 - WakeLock released
518. 27/3 6:46:18 - logger initialized again from AlarmOnScreen create //user said he unlocked phone then to check the time...
从现在的日志来看，我相信 WakeLock 确实在工作 - 如果 TimeoutReleaseThread 能够完成工作，那么所有 CPU 都必须一直在运行。
问题是为什么 AlarmOnScreen Activity 没有启动？为什么主要活动（第 511-514 行）开始了？最近我让 AlarmOnScreen 在清单中设置了 singleTask 模式。这会导致问题吗？但为什么？由于其他几个原因，我需要这个 singleTask...
设备是带有 2.3.6 Android 的 GT-S5830i。