Hi, I have done some more testing. It is working much better now in that each time there is an alarm a window pops up. In one last case though only after sliding the phone guard up I did find that the alarm window started to play late, so it is as though indeed the phone went back to sleep right after firing the activity (before such activity finished playing the sound). I must also admit that I now acquire the lock at the very beginning of the broadcast receiver that fires my activity, this may or may not have made the difference as well besides changing from a partial wakelock to a full wakelock. Anyways, I may have to hold the wakelock even longer to see if this other problem concerning the window only popping up when I unlock the phone goes away. (cause I am seeing the phone light up and quickly light down but then no sound). Actually as I speak even the intent does not make it in some cases, I just see the lightup, so I am going to have to recode.
Thanks, John Goche On Mon, Oct 24, 2011 at 12:25 AM, John Goche <johngoch...@googlemail.com>wrote: > > Thanks Kostya, > > I changed my wakelock from partial wakelock to full wakelock and that seems > to have fixed things, albeit > somewhat strangely. I now see the screen light up on each timer expiration. > I am going to do some more > testing and if things go wrong I will try releasing the wakelock from > inside the activity and implementing a > singleton pattenrn instance to hold the wakelock like you did. Right now it > seems strange to me that if a > wakelock is acquired (especially a full wakelock) that the CPU would go > back to sleep as soon as I > release it but maybe this is indeed the case in some scenarios, so I am > going to investigate this > matter somewhat further (although I hate having to waste so many minutes > just waiting for the > CPU to power down and then see if the alarm comes back on but anyways...). > > Thanks a lot, your post was very helpful! > > Let me know if you have any other ideas or wisdom to share, > > John Goche > > > On Sun, Oct 23, 2011 at 10:47 PM, Kostya Vasilyev <kmans...@gmail.com>wrote: > >> I would still recommend you repeat your test with a Notification >> (possibly with a sound), as the system should take care of holding the wake >> lock(s) as needed for the duration of the sound. >> >> As for implementing the wake locks in your code, to display an alert: >> >> First, take a look at the docs, the basic use is "create a wake lock" - >> "acquire the wake lock" - "release the wake lock". >> >> http://developer.android.com/reference/android/os/PowerManager.html >> >> When creating your wake lock, these two PowerManager flags can be >> particularly useful: ACQUIRE_CAUSES_WAKEUP and ON_AFTER_RELEASE. >> >> Second, the important thing is to acquire the wake lock early enough, >> inside onReceive is fine, so the device stays awake. >> >> Third, it's very important to release the lock when no longer needed. Here >> is some pseudo code from my current project that starts a service based on >> wake alarms. >> >> The alarm receiver is called while the system is holding its wake lock, >> and calls a static helper method in MyService, startForActionAlarm. This >> method creates the service's wake lock object if needed, and acquires it. >> Now it can return to AlarmReceiver.onReceive, which can return to Android, >> which can release its wake lock - but it's ok, because gWakeLock is now in >> effect. >> >> A short time later, the system creates the service (if needed), and calls >> its onStartCommand. Here the service does something, and releases the wake >> lock that it originally acquired in startForActionAlarm. >> >> AlarmReceiver: >> >> onReceive(Context context) { >> MyService.startForActionAlarm(context) >> } >> >> MyService: >> >> static WakeLock gWakeLock = null; >> >> static WakeLock getWakeLock(Cotext context) { >> if (gWakeLock == null) { >> get PowerManager from context >> gWakeLock = power manager . newWakeLock(...) >> } >> } >> >> static void startForActionAlarm(Context context) { >> getWakeLock(this).acquire(); >> >> Intent intent = new Intent(context, MyService.class); >> intent.setAction(ALARM_ACTION); >> >> if (context.startService(intent) == null) { >> // Failed to start itself, undo the lock >> getWakeLock(this).release(); >> } >> } >> >> void handleStart(Intent intent, int startId) { >> if (intent.getAction().equals(ALARM_ACTION)) { >> getWakeLock(this).release(); >> } >> } >> >> In your case, since the goal is to start an activity, the wake lock would >> perhaps be released at the end of in MyActivity.onStart, or perhaps a bit >> later, when the sound is done playing. >> >> Hope this helps. >> >> -- Kostya >> >> 24.10.2011 0:24, John Goche пишет: >> >> >> %%%%% So now I must learn how to keep the CPU running or when the alarm >> goes off I will not >> be able to pop up the window and play the sound. When I leave the phone >> for a while the CPU >> hybernates or something it seems, so my RTC_WAKEUP calls the broadcast >> receiver but does >> not pop up the intent it seems. >> >> Can someone please teach me how to use wakelocks and exactly what they are >> so that I may >> fix this problem either by keeping the CPU running all the time, or in >> some more efficient way >> if possible? >> >> >> -- >> Kostya Vasilyev >> >> -- >> You received this message because you are subscribed to the Google >> Groups "Android Developers" group. >> To post to this group, send email to android-developers@googlegroups.com >> To unsubscribe from this group, send email to >> android-developers+unsubscr...@googlegroups.com >> For more options, visit this group at >> http://groups.google.com/group/android-developers?hl=en >> > > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. 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