问如何通过长按示例键盘的某个键来打开首选项屏幕？

EN

   public void onClick(View v) {
   switch (v.getId()) {
   case R.id.btnPrefs:
      Intent intent = new Intent(PreferenceActivity.this,
      PrefsActivity.class);
      startActivity(intent);
      break;

btn.setOnLongClickListener(new OnLongClickListener() { 
        @Override
        public boolean onLongClick(View v) {
            // TODO Auto-generated method stub
            return true;
        }
    });