Question

I have an app that runs a countdown timer and brings up an alertbox when the timer runs out so that the game can restart. Unfortunately, when I hit the back button and open up the app again, it crashes around the time when the original countdowntimer should have run out.

The following code is located in onCreate of my Activity.

        CountDownTimer cdt = new CountDownTimer(totalTime*1000, 1000) { 
        public void onTick(long millisUntilFinished) {
            time = (int) ((millisUntilFinished)/1000)*100/totalTime;             
            TimeBar.setProgress(time);
        }

        public void onFinish() {
            time = 0;            
            TimeBar.setProgress(time);
            AlertDialog.Builder alertbox = new AlertDialog.Builder(mContext);
            alertbox.setMessage("Sweet! " + score + " points!");
            alertbox.setPositiveButton("Leaderboard", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface arg0, int arg1) {
                    ScoreloopManagerSingleton.get().onGamePlayEnded((double) score, null);
                    startActivity(new Intent(BubblesActivity.this, LeaderboardsScreenActivity.class));
                    BubblesActivity.this.finish();

                }
            });
            alertbox.setNeutralButton("Replay", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface arg0, int arg1) {
                    BubblesActivity.this.finish();
                    startActivity(new Intent(BubblesActivity.this, BubblesActivity.class));

                }
            });
            if(alertbox!= null)
                alertbox.show();



        }
    }.start();

Answer 1

Without a stack trace it’s hard to say what happens but it most likely has something to do you referencing a dead Activity from your CountDownTimer.

Calling enter code hereCountDownTimer.cancel() in onDestroy() would probably solve this.