On Wed, Apr 10, 2013 at 8:03 AM, plnelson <[email protected]> wrote: > I'm programming an Android device for use in an industrial environment > where it needs to stay in touch with the server even when the screen "goes > to sleep". I thought I did all the right stuff but when the screen goes out > it still sends a "Fin" to the server (confirmed on a network data packet > sniffer). > > I know that to do a WifiLock I must also do a WakeLock, so, in my onCreate > I do . . . > >> private PowerManager.WakeLock wakelock;private WifiManager.WifiLock wifilock; >> >> . . . >> >> PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE); >> wakelock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "CPUOnly"); >> wakelock.acquire(); >> WifiManager wifiManager = (WifiManager) >> getSystemService(Context.WIFI_SERVICE); >> wifilock = wifiManager.createWifiLock(WifiManager.WIFI_MODE_FULL, >> "WifiLock"); >> wifilock.acquire(); >> >>
Acquiring wifilock like this only makes sure the system does not shut down wifi. The actual wifi connection still goes through power optimizations once screen is off in the driver. This should not drop your connections, but we have seen some vendor driverss use optimizations that cause interop issues with certain access points leading to heavy loss or drops. > > I read on the web that this doesn't work on some devices and you have to > leave the screen on dim, so I replaced the line above with > > wakelock = pm.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK, >> "CPUOnly"); >> > > That "worked" in the sense that WiFi stayed on, but at the expense of > leaving the screen on dimly. Is there any workaround to this so the > screen can go off but WiFi stay on? > > ALSO - this is on an Android 2.36 device, but the Android documentation > says that as of API 17 SCREEN_DIM_WAKE_LOCK is deprecated and we're > supposed to use FLAG_KEEP_SCREEN_ON, but that leaves the display on at *full > brightness*! So what are we supposed to do then? > > Thanks in advance! > > > > -- > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > 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. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] 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. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
