My app crashes fatal exception Unable to add window

Question

I am very new to Android development and I have created this quiz game. My problem is the app randomly crashes after a few minutes it has been opened. The crashes are at random times so I can't figure out what causes the crashing. Below is the logcat error code whenever the app crashes

11-16 18:39:10.573 19023-19023/com.noxeternal.quizgame E/AndroidRuntime: FATAL EXCEPTION: main
                                                                     Process: com.noxeternal.quizgame, PID: 19023
                                                                     android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@d70d3e4 is not valid; is your activity running?
                                                                         at android.view.ViewRootImpl.setView(ViewRootImpl.java:679)
                                                                         at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:342)
                                                                         at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:94)
                                                                         at android.app.Dialog.show(Dialog.java:322)
                                                                         at com.noxeternal.quizgame.MainActivity.gameOver(MainActivity.java:287)
                                                                         at com.noxeternal.quizgame.MainActivity.access$300(MainActivity.java:19)
                                                                         at com.noxeternal.quizgame.MainActivity$9.onFinish(MainActivity.java:307)
                                                                         at android.os.CountDownTimer$1.handleMessage(CountDownTimer.java:127)
                                                                         at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                         at android.os.Looper.loop(Looper.java:154)
                                                                         at android.app.ActivityThread.main(ActivityThread.java:6176)
                                                                         at java.lang.reflect.Method.invoke(Native Method)
                                                                         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:888)
                                                                         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:778)

Here are the codes mentioned at the logcat.

private void gameOver(){
    AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(MainActivity.this);
    alertDialogBuilder
            .setMessage("Game over! Your score is " + mScore + " points.")
            .setCancelable(false)
            .setPositiveButton("NEW GAME",
                    new DialogInterface.OnClickListener(){
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i){
                            finish();
                            startActivity(new Intent(getApplicationContext(),MainActivity.class));
                        }
                    })
            .setNegativeButton("Exit",
                    new DialogInterface.OnClickListener(){
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i){
                            Intent intent = new Intent(MainActivity.this, MainMenu.class);
                            startActivity(intent);
                            finish();
                        }
                    });
    AlertDialog alertDialog = alertDialogBuilder.create();
    alertDialog.show();
}

private void startTimer(){
    long millisInFuture = 60000;
    long countDownInterval = 1000;

    timer.setText("Time remaining: " + timer);
    countDownTimer = new CountDownTimer(millisInFuture, countDownInterval) {
        @Override
        public void onTick(long millisUntilFinished) {
            if(isPaused){
                cancel();
            } else {
                timer.setText("Time remaining: " + millisUntilFinished / 1000);
                remainingTime = millisUntilFinished;
            }
        }
        @Override
        public void onFinish() {
            gameOver();
        }
    };
    countDownTimer.start();
}

Thank you!

This error will come mostly when you try to update your UI but activity was distroyed. can you please share your code here? — Samir Bhatt, Nov 16 '17 at 11:04

score 2 · Answer 1 · answered Nov 16 '17 at 11:06

when you look at the error, you may find some "links" from the lines that are giving error, you can click and find out. In your case, the errors are in:

MainActivity.class on line 287: MainActivity.java:287

MainActivity.class on line 19: MainActivity.java:19

MainActivity.class on line 307: MainActivity.java:307

I think this may help to identify the error.

score 0 · Accepted Answer · answered Nov 16 '17 at 11:18

0

Try to modify this code:

 @Override
 public void onClick(DialogInterface dialogInterface, int i){
     finish();
     startActivity(new Intent(getApplicationContext(),MainActivity.class));
 }

to this:

@Override
public void onClick(DialogInterface dialogInterface, int i) {         
     startActivity(new Intent(getApplicationContext(),MainActivity.class));
     finish();
}

answered Nov 16 '17 at 11:18

Ibrokhim Kholmatov

1,079
2
13
16

Hi. I think this is the trick. I am still observing if crashes will occur and will get back to you guys. Thanks! – Nox Eternal Nov 16 '17 at 11:34
Welcome! If your app is not crashing could you please accept the right answer? – Ibrokhim Kholmatov Nov 16 '17 at 13:06
Observed my app for more than an hour testing buttons and everything. Looks good right now. Marked as answer. Thanks! – Nox Eternal Nov 16 '17 at 13:47

My app crashes fatal exception Unable to add window

2 Answers2