progress bar

چرا proress bar به صفر reset نمیشه؟

ProgressBar p;
    mChronometer.stop();
    mChronometer.setBase(SystemClock.elapsedRealtime());finalTextView txtlevel=(TextView) findViewById(R.id.txtlevel);AlertDialog.Builder alertDialogBuilder =newAlertDialog.Builder(c);
    alertDialogBuilder.setTitle("Game over");
    alertDialogBuilder.setMessage("Are you sure to retry?").setCancelable(false).setNegativeButton("Yes",newDialogInterface.OnClickListener(){publicvoid onClick(DialogInterface dialog,int id){
            dialog.cancel();
            level =1;
            p.setProgress(0);
            mChronometer.start();
            setVals(c);
            txtlevel.setPadding(48,40,0,0);
            txtlevel.setText(String.valueOf(level));}}).setPositiveButton("Exit",newDialogInterface.OnClickListener(){publicvoid onClick(DialogInterface dialog,int id){MainActivity.this.finish();}});AlertDialog alertDialog = alertDialogBuilder.create();
    alertDialog.show();