[android-developers] Re: PARTIAL_WAKE_LOCK and thread running in a service

Get the lock in the oncreate of the service and release it at the end
of the thread

On Sep 9, 4:41 am, Evelyon <evely...@gmail.com> wrote:
> I have got a service which runs a thread. The thread save some data in
> a file (in the sdcard). When Android goes to sleep, I need that the
> service and the thread continue running. I tried it with a
> PARTIAL_WAKE_LOCK, but it doesn't work; the thread stops while Android
> is sleeping. Other locks like FULL_WAKE_LOCK works, but I need to use
> PARTIAL_WAKE_LOCK because, in the future, in that thread I will read
> from a serial port and I don't care the screen turn off.
>
> I don't know if I have some mistake in the code, or if I don't
> understand the PARTIAL_WAKE_LOCK. Somebody can tell me why my solution
> doesn't wrok?
>
> This is part of the code of the main activity, where the service is
> stareted:
>
>     public void onClick(View v) {
>         if (SerialPortService.WAKELOCK == null) {
>             PowerManager pm = (PowerManager)
> getSystemService(Context.POWER_SERVICE);
>             SerialPortService.WAKELOCK =
> pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
> SerialPortService.WL_TAG);
>             SerialPortService.WAKELOCK.acquire();
>             startService(new Intent(getApplicationContext(),
> SerialPortService.class));
>         }
>     }
>
> This is the code of the service:
>
>     public class SerialPortService extends Service {
>
>         public static String WL_TAG = "serial_port_wl_tag";
>         public static PowerManager.WakeLock WAKELOCK = null;
>         private BufferedWriter out = null;
>
>         public IBinder onBind(Intent intent) {
>             return null;
>         }
>
>         public void onCreate() {
>             super.onCreate();
>             try {
>                 File root = Environment.getExternalStorageDirectory();
>                 if (root.canWrite()){
>                     File dataFile = new File(root, "batterytest.txt");
>                     FileWriter dataFileWritter = new
> FileWriter(dataFile);
>                     out = new BufferedWriter(dataFileWritter);
>                 }
>             } catch (IOException ioe) {
>                 Log.d("TEST", "Could not open file " +
> ioe.getMessage());
>             }
>             readThread = new ReadThread();
>             readThread.start();
>         }
>
>         public void onDestroy() {
>             if (readThread != null) readThread.interrupt();
>             WAKELOCK.release();
>             WAKELOCK = null;
>             try {
>                 out.close();
>             } catch (IOException ioe) {
>                 Log.d("TEST", "Could not close file " +
> ioe.getMessage());
>             }
>             super.onDestroy();
>         }
>
>         private class ReadThread extends Thread {
>             public void run() {
>                 super.run();
>                 while (!isInterrupted()) {
>                     try {
>                         Thread.sleep(5000);
>                         if (out != null) {
>                             Calendar now = Calendar.getInstance();
>                             out.write(now.getTime().toString());
>                             out.newLine();
>                     } catch (IOException ioe) {
>                         Log.d("TEST", "Could not read file " +
> ioe.getMessage());}
>                         return;
>                     } catch (InterruptedException e) {
>                         return;
>                     }
>                 }
>             }
>
>         }
>
>     }

--
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+unsubscribe@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/android-developers?hl=en