AlertBuilder showing an exception. DialogBox is not opening [duplicate]

Question

In the following code I want to open the dialog box when the mIndex is 0.

The code is going in the 'if' part. But is not opening the dialog Box instead showing the following exception.

Code:

mIndex = (mIndex+1)%mQuestionBank.length;
    if(mIndex == 0 )
    {
        Log.d("Quizzler", "Inside IF");
        AlertDialog.Builder alert = new AlertDialog.Builder(getApplicationContext());
        alert.setTitle("Game Over");
        alert.setCancelable(false);
        alert.setMessage("Your score is "+mScore);
        alert.setPositiveButton("Close Application", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                finish();
            }
        });
        alert.show();
    }

Exception:

FATAL EXCEPTION: main
                                                                  Process: com.londonappbrewery.quizzler, PID: 11560                                                                               android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
                                                                               at android.view.ViewRootImpl.setView(ViewRootImpl.java:714)
                                                                               at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:342)
                                                                               at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:94)
                                                                               at android.app.Dialog.show(Dialog.java:316)
                                                                               at android.app.AlertDialog$Builder.show(AlertDialog.java:1112)
                                                                               at com.londonappbrewery.quizzler.MainActivity.updateQuestion(MainActivity.java:100)
                                                                               at com.londonappbrewery.quizzler.MainActivity.access$100(MainActivity.java:16)
                                                                               at com.londonappbrewery.quizzler.MainActivity$1.onClick(MainActivity.java:69)
                                                                               at android.view.View.performClick(View.java:5609)
                                                                               at android.view.View$PerformClick.run(View.java:22263)
                                                                               at android.os.Handler.handleCallback(Handler.java:751)
                                                                               at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                               at android.os.Looper.loop(Looper.java:154)
                                                                               at android.app.ActivityThread.main(ActivityThread.java:6077)
                                                                               at java.lang.reflect.Method.invoke(Native Method)
                                                                               at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
                                                                               at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)

Answer 1

Instead of

new AlertDialog.Builder(getApplicationContext());

Try using

new AlertDialog.Builder(MainActivity.this);