Android8.0 AlarmManagerService

只是做下笔记

关于闹铃怎么触发的，当你设置好闹铃后，时间到了就会走这里触发。前面的流程不分析。闹铃触发就是发一个广播给你自己的app（alarm.operation.send），然后做处理。你可以显示一个闹钟界面，也可以是service做一些处理。

这里好像有2中形式，看注释。不是很清楚。
PendingIntent alarm
Direct listener callback alarm
Alarm alarm包含了一些信息，比如packagename，等等。

frameworks/base/services/core/java/com/android/server/AlarmManagerService.java

        /**         * Deliver an alarm and set up the post-delivery handling appropriately         */        public void deliverLocked(Alarm alarm, long nowELAPSED, boolean allowWhileIdle) {            if (alarm.operation != null) {  // PendingIntent alarm                try {                    Log.i("a", "deliverLocked alarm.operation.send ----------");                    Log.i("a", ""+alarm);                    if(alarm.alarmClock!=null)                    Log.i("a", ""+alarm.alarmClock);                    Log.i("a", "----------------------");                    alarm.operation.send(getContext(), 0,                            mBackgroundIntent.putExtra(                                    Intent.EXTRA_ALARM_COUNT, alarm.count),                                    mDeliveryTracker, mHandler, null,                                    allowWhileIdle ? mIdleOptions : null);                } catch (PendingIntent.CanceledException e) {                    if (alarm.repeatInterval > 0) {                        // This IntentSender is no longer valid, but this                        // is a repeating alarm, so toss it                        removeImpl(alarm.operation);                    }                    // No actual delivery was possible, so the delivery tracker's                    // 'finished' callback won't be invoked.  We also don't need                    // to do any wakelock or stats tracking, so we have nothing                    // left to do here but go on to the next thing.                    return;                }            } else {                if(mNotificationManager.getZenMode()==Global.ZEN_MODE_GAME&&alarm.alarmClock!=null) {                    return;                }                // Direct listener callback alarm                try {                    if (DEBUG_LISTENER_CALLBACK) {                        Slog.v(TAG, "Alarm to uid=" + alarm.uid                                + " listener=" + alarm.listener.asBinder());                    }                    alarm.listener.doAlarm(this);                    mHandler.sendMessageDelayed(                            mHandler.obtainMessage(AlarmHandler.LISTENER_TIMEOUT,                                    alarm.listener.asBinder()),                            mConstants.LISTENER_TIMEOUT);                } catch (Exception e) {                    if (DEBUG_LISTENER_CALLBACK) {                        Slog.i(TAG, "Alarm undeliverable to listener "                                + alarm.listener.asBinder(), e);                    }                    // As in the PendingIntent.CanceledException case, delivery of the                    // alarm was not possible, so we have no wakelock or timeout or                    // stats management to do.  It threw before we posted the delayed                    // timeout message, so we're done here.                    return;                }            }            // The alarm is now in flight; now arrange wakelock and stats tracking            if (DEBUG_WAKELOCK) {                Slog.d(TAG, "mBroadcastRefCount -> " + (mBroadcastRefCount + 1));            }            if (mBroadcastRefCount == 0) {                setWakelockWorkSource(alarm.operation, alarm.workSource,                        alarm.type, alarm.statsTag, (alarm.operation == null) ? alarm.uid : -1,                        true);                if (!mWakeLock.isHeld()) {                mWakeLock.acquire();                }                mHandler.obtainMessage(AlarmHandler.REPORT_ALARMS_ACTIVE, 1).sendToTarget();            }            final InFlight inflight = new InFlight(AlarmManagerService.this,                    alarm.operation, alarm.listener, alarm.workSource, alarm.uid,                    alarm.packageName, alarm.type, alarm.statsTag, nowELAPSED);            mInFlight.add(inflight);            mBroadcastRefCount++;            qcNsrmExt.addTriggeredUid((alarm.operation != null) ?                                    alarm.operation.getCreatorUid() :                                    alarm.uid);            if (allowWhileIdle) {                // Record the last time this uid handled an ALLOW_WHILE_IDLE alarm.                mLastAllowWhileIdleDispatch.put(alarm.uid, nowELAPSED);                if (RECORD_DEVICE_IDLE_ALARMS) {                    IdleDispatchEntry ent = new IdleDispatchEntry();                    ent.uid = alarm.uid;                    ent.pkg = alarm.packageName;                    ent.tag = alarm.statsTag;                    ent.op = "DELIVER";                    ent.elapsedRealtime = nowELAPSED;                    mAllowWhileIdleDispatches.add(ent);                }            }            final BroadcastStats bs = inflight.mBroadcastStats;            bs.count++;            if (bs.nesting == 0) {                bs.nesting = 1;                bs.startTime = nowELAPSED;            } else {                bs.nesting++;            }            final FilterStats fs = inflight.mFilterStats;            fs.count++;            if (fs.nesting == 0) {                fs.nesting = 1;                fs.startTime = nowELAPSED;            } else {                fs.nesting++;            }            if (alarm.type == ELAPSED_REALTIME_WAKEUP                    || alarm.type == RTC_WAKEUP) {                bs.numWakeup++;                fs.numWakeup++;                if (alarm.workSource != null && alarm.workSource.size() > 0) {                    for (int wi=0; wi<alarm.workSource.size(); wi++) {                        final String wsName = alarm.workSource.getName(wi);                        ActivityManager.noteWakeupAlarm(                                alarm.operation, alarm.workSource.get(wi),                                (wsName != null) ? wsName : alarm.packageName,                                alarm.statsTag);                    }                } else {                    ActivityManager.noteWakeupAlarm(                            alarm.operation, alarm.uid, alarm.packageName, alarm.statsTag);                }            }        }    }}