android - 在 fragment android中创建listview

Question

作为标题，我想在 Fragment 中创建一个带有自定义行的 ListView 。我的代码如下。

fragment 类

public class PhotosFragment extends Fragment{

public PhotosFragment(){}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment_photos, container, false);

    ArrayList<ListviewContactItem> listContact = GetlistContact();
    ListView lv = (ListView)getActivity().findViewById(R.id.lv_contact);
    lv.setAdapter(new ListviewContactAdapter(getActivity(), listContact));

    return rootView;
}

private ArrayList<ListviewContactItem> GetlistContact(){
    ArrayList<ListviewContactItem> contactlist = new ArrayList<ListviewContactItem>();

    ListviewContactItem contact = new ListviewContactItem();

    contact.SetName("Topher");
    contact.SetPhone("01213113568");
    contactlist.add(contact);

    contact = new ListviewContactItem();
    contact.SetName("Jean");
    contact.SetPhone("01213869102");
    contactlist.add(contact);

    contact = new ListviewContactItem();
    contact.SetName("Andrew");
    contact.SetPhone("01213123985");
    contactlist.add(contact);

    return contactlist; 
    }   
}

适配器类

public class ListviewContactAdapter extends BaseAdapter{
private static ArrayList<ListviewContactItem> listContact;

private LayoutInflater mInflater;

public ListviewContactAdapter(Context photosFragment, ArrayList<ListviewContactItem> results){
    listContact = results;
    mInflater = LayoutInflater.from(photosFragment);
}

@Override
public int getCount() {
    // TODO Auto-generated method stub
    return listContact.size();
}

@Override
public Object getItem(int arg0) {
    // TODO Auto-generated method stub
    return listContact.get(arg0);
}

@Override
public long getItemId(int arg0) {
    // TODO Auto-generated method stub
    return arg0;
}


public View getView(int position, View convertView, ViewGroup parent) {
    // TODO Auto-generated method stub
    ViewHolder holder;
    if(convertView == null){
        convertView = mInflater.inflate(R.layout.contact_item, null);
        holder = new ViewHolder();
        holder.txtname = (TextView) convertView.findViewById(R.id.lv_contact_item_name);          
        holder.txtphone = (TextView) convertView.findViewById(R.id.lv_contact_item_phone);

        convertView.setTag(holder);
    } else {
        holder = (ViewHolder) convertView.getTag();
    }

    holder.txtname.setText(listContact.get(position).GetName());
    holder.txtphone.setText(listContact.get(position).GetPhone());

    return convertView;
}

static class ViewHolder{
    TextView txtname, txtphone;
}
}

但是当我运行应用程序时，什么都没有显示。谁能告诉我这里出了什么问题，我该如何解决？

Answer 1

我猜你的应用程序崩溃是因为 NullPointerException。

改变这个

ListView lv = (ListView)getActivity().findViewById(R.id.lv_contact);

到

ListView lv = (ListView)rootView.findViewById(R.id.lv_contact);

假设listview属于 fragment 布局。

其余的代码看起来还不错

编辑:

好吧，既然你说它不起作用，我自己试过了