Android开发中怎么实现给app设置铃声

//选择铃声  public void toChoose(View view) {   Intent intent = new Intent(RingtoneManager.ACTION_RINGTONE_PICKER);   intent.putExtra(RingtoneManager.EXTRA_RINGTONE_TYPE, RingtoneManager.TYPE_NOTIFICATION);   intent.putExtra(RingtoneManager.EXTRA_RINGTONE_TITLE, "设置通知铃声");   if (myUriStr != null) {    <span >intent.putExtra(RingtoneManager.EXTRA_RINGTONE_EXISTING_URI, Uri.parse(myUriStr));</span>//将已经勾选过的铃声传递给系统铃声界面进行显示   }   startActivityForResult(intent, 0);  }    @Override  protected void onActivityResult(int requestCode, int resultCode, Intent data) {   try {    <span >Uri pickedUri = data.getParcelableExtra(RingtoneManager.EXTRA_RINGTONE_PICKED_URI);</span>//获取用户选择的铃声数据    myUriStr = pickedUri.toString();    } catch (Exception e) {    e.printStackTrace();   }  }