關於自定義BaseAdapter listAdapter時，出現超低級問題

private BaseAdapter listAdapter = new BaseAdapter() {

@Override
public View getView(int position, View convertView, ViewGroup parent) {

Log.d(Constants.LOG_TAG, "listAdapter position = " + position);

//應該爲 convertView == null

if(convertView != null){
convertView = getLayoutInflater().inflate(R.layout.pull_to_refresh_item ,parent ,false);
}
return convertView;
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public Object getItem(int position) {
return null;
}

@Override
public int getCount() {
return length;
}

};

低級問題，寫上博客，警示自己。