应用程序在 count 和 dialog box上崩溃

Question

我使用下面的代码:public class MyCount extends CountDownTimer    {         public MyCount(long millisInFuture, long countDownInterval)          {             super(millisInFuture, countDownInterval);         }         @Override         public void onFinish()          {              displayAlertForRestart();         }         @Override         public void onTick(long millisUntilFinished)          {             counter.setText("Time Left: " + millisUntilFinished/1000 + " sec");         }      }    public void displayAlertForRestart()    {     AlertDialog.Builder builder = new AlertDialog.Builder(this);     builder.setCancelable(true);     builder.setMessage("Do you want to Restart?");     builder.setTitle("Game Over");     builder.setInverseBackgroundForced(true);     builder.setPositiveButton("Yes", new DialogInterface.OnClickListener()     {       public void onClick(DialogInterface dialog, int which) {             Intent myIntent = new Intent(context,Level.class);             startActivity(myIntent);             dialog.dismiss();             finish();       }       });     builder.setNegativeButton("No", new DialogInterface.OnClickListener() {       public void onClick(DialogInterface dialog, int which) {         dialog.dismiss();         finish();       }     });     AlertDialog alert = builder.create();     alert.show();    }alert.show();处的 LogCat error：36: E/AndroidRuntime(9829): android.view.WindowManager$BadTokenException: Unable to add window -- token android. os.BinderProxy@43cf1e38 is not valid; is your activity running?

Answer 1

AlertDialog.Builder builder = new AlertDialog.Builder(this);
参数应该是一个activity的引用.