Service: do not crash on service restart after reboot

src/SystemEventReceiver.scala

@@ -1,6 +1,7 @@
 package org.aprsdroid.app
 
 import android.content.{BroadcastReceiver, Context, Intent}
+import android.os.Build
 
 class SystemEventReceiver extends BroadcastReceiver {
 	val TAG = "APRSdroid.SystemEventReceiver"
@@ -8,7 +9,12 @@ class SystemEventReceiver extends BroadcastReceiver {
 	override def onReceive(ctx : Context, i : Intent) {
 		android.util.Log.d(TAG, "onReceive: " + i)
 		val prefs = new PrefsWrapper(ctx)
-		if (prefs.getBoolean("service_running", false))
-			ctx.startService(AprsService.intent(ctx, AprsService.SERVICE))
+		if (prefs.getBoolean("service_running", false)) {
+                        val i = AprsService.intent(ctx, AprsService.SERVICE)
+                        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
+                                ctx.startForegroundService(i)
+                        else
+                                ctx.startService(i)
+                }
 	}
 }