Question

所以我做了一个滑动标签应用程序，将json加载到listview中。我的问题是我如何实现只能在开头加载5个listview项目并在向下滚动时加载另外5个项目的东西？（而不是在开头加载所有listview项目）

我在网上搜索，但我真的不明白如何做到这一点。任何建议或想法将不胜感激。

这是我的一些代码。这些类是我认为代码可以去的地方：我使用了SlidingTabLayout＆amp;从Android开发者网站剥离。

CustomListAdapter代码：

public class CustomListAdapter extends BaseAdapter {
private Activity activity;
private LayoutInflater inflater;
private List<Tanga> tangasItems;
ImageLoader imageLoader = AppController.getInstance().getImageLoader();

public CustomListAdapter(Activity activity, List<Tanga> movieItems) {
    this.activity = activity;
    this.tangasItems = movieItems;
}

@Override
public int getCount() {
    return tangasItems.size();
}

@Override
public Object getItem(int location) {
    return tangasItems.get(location);
}

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

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

    if (inflater == null)
        inflater = (LayoutInflater) activity
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    if (convertView == null)
        convertView = inflater.inflate(R.layout.list_row, null);

    TextView name = (TextView) convertView.findViewById(R.id.name);

    // getting movie data for the row
    Tanga m = tangasItems.get(position);

    // title
    name.setText(m.getName());

    return convertView;
}

}

片段：

public class Tab1 extends Fragment {
private static final String url = "website.json";
private List<Tanga> tangaList = new ArrayList<Tanga>();
private ListView listView;
private CustomListAdapter adapter;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}

public void onActivityCreated (Bundle savedInstanceState){
    super.onActivityCreated(savedInstanceState);

    listView = (ListView) getView().findViewById(R.id.list);
    adapter = new CustomListAdapter(getActivity(), tangaList);
    listView.setAdapter(adapter);
    JsonArrayRequest movieReq = new JsonArrayRequest(url,
            new Response.Listener<JSONArray>() {
                @Override
                public void onResponse(JSONArray response) {
                    // Parsing json
                    for (int i = 0; i < response.length(); i++) {
                        try {

                            JSONObject obj = response.getJSONObject(i);
                            Tanga movie = new Tanga();

                            //name
                            String name = obj.getString("name");
                            movie.setName(name);


                            // adding movie to movies array
                            tangaList.add(movie);

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }

                    // notifying list adapter about data changes
                    // so that it renders the list view with updated data
                    adapter.notifyDataSetChanged();
                }
            }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            VolleyLog.d("Error: ");

        }
    });

    // Adding request to request queue
    AppController.getInstance().addToRequestQueue(movieReq);

}


@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.tabs, container, false);

    return v;
}
}

Tanga代码:(型号）

public class Tanga {
private String name;

public Tanga() {
}

public Tanga(String name) {
    this.name = name;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

}

Answer 1

您可以通过多种方式处理此问题，最简单的方法是创建ArrayList类型的Tanga，让我们假设它的名称为{{1} }。你需要做的就是在for循环中编写这段代码。

tangaList2

此后，您还应该在片段中实现onScrollListener：

public void onResponse(JSONArray response) {
                // Parsing json
                for (int i = 0; i < response.length(); i++) {
                    try {

                        JSONObject obj = response.getJSONObject(i);
                        Tanga movie = new Tanga();

                        //name
                        String name = obj.getString("name");
                        movie.setName(name);


                        // adding movie to movies array
                        if(i < 5) {
                        tangaList.add(movie);
                        }
                        else { 
                        tangaList2.add(movie);
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }

                // notifying list adapter about data changes
                // so that it renders the list view with updated data
                adapter.notifyDataSetChanged();
            }

（Android）ListView：向下滚动时一次加载5个项目

1 个答案: