我是一名初学Android开发的新手,也是第一次使用可扩展列表视图。我正在创建一个应用程序,在其中从Web服务获取可扩展列表视图的所有内容。我也从webservice获取了所有内容,但当在可扩展列表视图中父项没有子项时,可扩展列表视图的自定义适配器方法getchildcount()会返回null,并引发空指针异常。如何只在列表中显示没有子项的父项以及当两者都可用时怎么办?谢谢。
public View getChildView(int p_id, int c_id, boolean bln1, View view,ViewGroup viewgroup) {
// TODO Auto-generated method stub
if (view == null) {
view = inflater.inflate(com.example.eventlive.R.layout.homescreen_list_item_child, viewgroup,false);
}
TextView textView = (TextView) view.findViewById(R.id.list_item_text_child);
//"i" is the position of the parent/group in the list and
//"i1" is the position of the child
textView.setText(mParent.get(p_id).getArrayChildren().get(c_id));
view.setBackgroundResource(R.drawable.child_bg);
//return the entire view
return view;
}
//counts the number of children items so the list knows how many times calls getChildView() method
@Override
public int getChildrenCount(int p_id) {
// TODO Auto-generated method stub
return mParent.get(p_id).getArrayChildren().size();
}