Question

I have managed to save my SIM card serial into the packagename.preferences.xml inside a string called serial but now i want to compare my current serial.

When i boot up my phone using the android.intent.boot_completed broadcast receiver. The value inside String value = sp.getString(“serial”, “”); i am unable to get the current value of the serial string to compare properly.

         TelephonyManager tMgr=(TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);
         String currentSerial = tMgr.getSimSerialNumber();

         Toast.makeText(context, "Current Serial Number: " + currentSerial, Toast.LENGTH_LONG).show();

 SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(context);
 String value = sp.getString("serial", "");

 if (value == currentSerial)
 {
     Toast.makeText(context, "SIM Change detected!", Toast.LENGTH_SHORT).show();
 }
 else {
     Toast.makeText(context, "No SIM Change detected!", Toast.LENGTH_SHORT).show();
 }

Answer 1

You are probably not getting the same SharedPreferences. Try specifying the SharedPrefereneces name for both and/or using your base context for each.