对话框不会在按下按钮时触发解除侦听器

    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
    final EditText input = new EditText(MainActivity.this);
    builder.setView(input);
    builder.setPositiveButton("OK", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int which)
        {
            // ok stuff
        }
    });
    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int which)
        {
            // cancel stuff
        }
    });
    builder.setOnDismissListener(new DialogInterface.OnDismissListener()
    {
        @Override
        public void onDismiss(DialogInterface dialog)
        {
            //dismiss stuff
        }
    });
    builder.show();