private void startGame() { ISharedPreferences sPref = PreferenceManager.GetDefaultSharedPreferences(this); string diff = sPref.GetString("difficultyPref", ""); Stream ist = null; if (diff.Equals("Medium")) { ist = Resources.OpenRawResource(Resource.Raw.medium); } else if (diff.Equals("Hard")) { ist = Resources.OpenRawResource(Resource.Raw.hard); } else { ist = Resources.OpenRawResource(Resource.Raw.easy); } GameController.getInstance().setInitial(SudokuFileReader.getRandSudoku(ist)); GameController.getInstance().clean(); FindViewById(Resource.Id.game_field).Invalidate(); }