Intent java.lang.NullPointerException:

Good day,

I came across a problem with restarting activity. When you run the restartTheGame function directly at the touch of a button, no problems arise, everything works.

But if I call this method from AlertDialog, the application crashes.

E/AndroidRuntime: FATAL EXCEPTION: main Process: com.fgurbanov.skynet.myminesweeper, PID: 4506 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Context.getPackageName()' on a null object reference at android.content.ContextWrapper.getPackageName(ContextWrapper.java:133) at android.content.ComponentName.<init>(ComponentName.java:128) at android.content.Intent.<init>(Intent.java:4449) at com.fgurbanov.skynet.myminesweeper.GameActivity.restartGame(GameActivity.java:98) at com.fgurbanov.skynet.myminesweeper.GameActivity$2.onClick(GameActivity.java:172) at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:163) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main(ActivityThread.java:5417) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 

I will be glad to any hint for solving the problem.

  <Button android:text="Restart" android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/Restart_button" android:layout_alignParentEnd="true" android:onClick="restartTheGame"/> 

Activity code itself

 public class GameActivity extends AppCompatActivity { private static TextView scoreTextView; private static TextView flagTextView; public String[] ScoreList; static SharedPreferences sPref; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_game); //определим счетчики scoreTextView = (TextView) findViewById(R.id.score); flagTextView = (TextView) findViewById(R.id.mine_left); //загрузим данные прошлых игр loadScoreList(); //Log.e("something Load", ScoreList[0]); //запустим игру Intent intent = getIntent(); int size = intent.getIntExtra("size", 0); Log.e("size"," "+size); if (size > 2){ int[][] genGrid = new int[size][size]; for (int i = 0; i < size; i++){ genGrid[i] = intent.getIntArrayExtra("step_"+i); } GameEngine.getInstance().createGrid(this,genGrid); } else { GameEngine.getInstance().createGrid(this); } } public static TextView getScoreTextView() { return scoreTextView; } public static TextView getFlagTextView() { return flagTextView; } private static GameActivity instance; public static GameActivity getInstance() { if ( instance == null ){ instance = new GameActivity(); } return instance; } public void saveLastResult(){ SaveScoreList(); } public void restartTheGame(View view) { //Intent intent = new Intent(GameActivity.this, GameActivity.class); Intent intent = getIntent(); //intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION); int[][] genGrid = GameEngine.getInstance().GenerateGrid; intent.putExtra("size",genGrid[0].length); for (int i = 0; i < genGrid.length; i++ ){ intent.putExtra("step_" + i,genGrid[i]); } finish(); startActivity(intent); this.overridePendingTransition(0, 0); } public void startNewGame(){ Intent intent = getIntent(); intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION); GameEngine.getInstance().isGameEnd = false; finish(); overridePendingTransition(0, 0); startActivity(intent); overridePendingTransition(0, 0); } public void checkEndGame(final View view) { if (GameEngine.getInstance().isGameEnd){ String title = "Game Over"; if (GameEngine.getInstance().isGameFailed) { title += " YOU DIED"; } else { title += "YOU WIN"; } String message = "Your Score " + GameEngine.getInstance().getScore(); Log.e("GameActivity.this", GameActivity.this.toString()); Log.e("this", this.toString()); Log.e("getInstance", getInstance().toString()); AlertDialog.Builder builder = new AlertDialog.Builder(view.getContext()); builder.setTitle(title); builder.setMessage(message); builder.setCancelable(false); builder.setPositiveButton("End", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { saveLastResult(); finish(); System.exit(0); dialog.cancel(); } }); builder.setNeutralButton("Restart", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { //restartGame();////////////////////////// restartTheGame(view); dialog.cancel(); } }); builder.setNegativeButton("Start NewGame", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { saveLastResult(); startNewGame(); dialog.cancel(); } }); AlertDialog alert = builder.create(); alert.show(); } } public void refreshLayer(View view) { int flag = GameEngine.getInstance().getFlag(); flagTextView.setText(Integer.toString(flag)); int score = GameEngine.getInstance().getScore(); scoreTextView.setText(Integer.toString(score)); checkEndGame(view); } public void SaveScoreList() { sPref = PreferenceManager .getDefaultSharedPreferences(this); sPref = getPreferences(MODE_PRIVATE); SharedPreferences.Editor ed = sPref.edit(); ed.putInt("Status_size", ScoreList.length); for (int i = 0; i < ScoreList.length; i++ ){ ed.putString("Status_" + i, ScoreList[i]); } ed.apply(); //ed.commit(); Toast.makeText(this, "Score saved", Toast.LENGTH_SHORT).show(); } public void loadScoreList() { sPref = PreferenceManager .getDefaultSharedPreferences(this); int size = sPref.getInt("Status_size", 0); if ( size < 2 ){ ScoreList = getResources().getStringArray(R.array.default_result); } else { for (int i = 0; i < size; i++) { ScoreList[i] = sPref.getString("Status_" + i, ""); } } } }