fixed position: use AlarmManager for reliable wakeups

src/location/FixedPosition.scala

@@ -1,31 +1,61 @@
 package org.aprsdroid.app
 
+import _root_.android.app.AlarmManager
+import _root_.android.app.PendingIntent
+import _root_.android.content.BroadcastReceiver
 import _root_.android.content.Context
+import _root_.android.content.Intent
+import _root_.android.content.IntentFilter
 import _root_.android.location.Location
 import _root_.android.os.{Bundle, Handler}
 import _root_.android.util.Log
 
 class FixedPosition(service : AprsService, prefs : PrefsWrapper) extends LocationSource {
 	val TAG = "APRSdroid.FixedPosition"
-	val periodicPoster = new Runnable() { override def run() { postPosition(); postRefresh(); } }
+	val ALARM_ACTION = "org.aprsdroid.app.FixedPosition.ALARM"
+
+	val intent = new Intent(ALARM_ACTION)
+	val pendingIntent = PendingIntent.getBroadcast(service, 0, intent,
+			PendingIntent.FLAG_UPDATE_CURRENT)
+
+	// get called on alarm
+	val receiver = new BroadcastReceiver() {
+		override def onReceive(ctx : Context, i : Intent) {
+			Log.d(TAG, "onReceive: " + i)
+			postPosition()
+			postRefresh()
+		}
+	}
+
+	val manager = service.getSystemService(Context.ALARM_SERVICE).asInstanceOf[AlarmManager]
+
+	var alreadyRunning = false
 
 	override def start(singleShot : Boolean) = {
-		stop()
+		if (alreadyRunning)
+			stop()
+		alreadyRunning = true
+
+		service.registerReceiver(receiver, new IntentFilter(ALARM_ACTION))
 		postPosition()
 		if (!singleShot)
 			postRefresh()
 
+
 		service.getString(R.string.p_source_manual)
 	}
 
 	override def stop() {
-		service.handler.removeCallbacks(periodicPoster)
+		manager.cancel(pendingIntent)
+		service.unregisterReceiver(receiver)
 	}
 
 	def postRefresh() {
 		// get update interval
 		val upd_int = prefs.getStringInt("interval", 10)
-		service.handler.postDelayed(periodicPoster, upd_int*60*1000)
+		Log.d(TAG, "postRefresh(): " + upd_int + " min")
+		manager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + upd_int*60*1000,
+			pendingIntent)
 	}
 
 	def postPosition() {
@@ -34,4 +64,5 @@ class FixedPosition(service : AprsService, prefs : PrefsWrapper) extends Locatio
 		location.setLongitude(prefs.getStringFloat("manual_lon", 0))
 		service.postLocation(location)
 	}
+
 }