ListView之重构

1 目标

listview是使用率非常高的，尽量少的代码完成listview功能，这里设计一种基于网络的可上下刷新的listview：【NetRefreshListView】

2 API调用

某个Activity使用【NetRefreshListView】时，只需要完成下面两个API调用

2.1 初始化

1 NetRefreshListView  netRefreshListView = new NetRefreshListView<CourseBean>(ConstUtil.COURSE_LIST, R.layout.homev4_listitem_hotcourse_layout, this);
2 netRefreshListView.refresh();

其中构造函数的解释：

1  /**
2      * 构造函数：
3      * 1 netype: 网络URL
4      * 2 adapterres：adapter的资源id
5      * 3 INetRefreshListListener：监听器，用于获取activit相关信息*/
6     public NetRefreshListView(String netype, int adapterres, final INetRefreshListListener in_listener) {}

View Code

2.2 实现接口

 1 public interface INetRefreshListListener {
 2         void onItemClickListener(int position, String netype); //点击时处理逻辑
 3 
 4         void netList(int index, String netype); //获取第几页的数据
 5 
 6         void isEnd(String netype); //已经到了尾部
 7 
 8         int getDataTotalSize(String netype); //获取所有数据的数量
 9 
10         void drawUIWithList(String netype); //网络有数据时，渲染UI
11 
12         void drawUIWithEmptyList(String netype);//网络无数据时，渲染UI
13 
14         Context getContext();  //获取上下文
15 
16         void setAdapterConvert(BaseViewHolder viewHolder, Object t, String jjNetype); //初始化adapter
17 
18         PullToRefreshListView onGetPullToRefreshListView(String netype); //获取UI级list
19     }

3 API特点

该API依赖PullToRefreshListView，实现顶部尾部下拉刷新，再结合xutils 的网络访问便可以轻松实现listview功能，相比pulltorefreshlistview，这次重构有以下几个优点：

3.1 不再写：判断是否重新加载、更多加载之类的代码，节省50行代码量

3.2 精简网络访问的API，只需要调用【netlist】方法便可以

3.3 精简adapter，只需复写【setAdapterConvert】方法便可以，不再每次额外新建一个adapter类

4 未考虑地方

4.1 listview的局部数据更新

4.2 判断是否加载更多的方法【getDataTotalSize】，有待继续完善，不能适配所有，这里之所以这样做，因为后台服务端给提供一个total字段来识别之。

5 源码

  1 package com.huisharing.pbook.controller.util;
  2 
  3 import android.content.Context;
  4 import android.os.Handler;
  5 import android.os.Message;
  6 import android.util.Log;
  7 import android.view.View;
  8 import android.widget.AdapterView;
  9 
 10 import com.huisharing.pbook.adapter.base.BaseViewHolder;
 11 import com.huisharing.pbook.adapter.base.MyBaseAdapter;
 12 import com.huisharing.pbook.widget.PullToRefreshBase;
 13 import com.huisharing.pbook.widget.PullToRefreshListView;
 14 
 15 import java.lang.reflect.Constructor;
 16 import java.util.ArrayList;
 17 import java.util.List;
 18 
 19 /**
 20  * 基于网络获取的listview
 21  * Created by Administrator on 2016/8/13.
 22  */
 23 public class NetRefreshListView<T> {
 24     PullToRefreshListView listView;
 25     MyBaseAdapter adapter;
 26     List list = new ArrayList<>(4);
 27     INetRefreshListListener m_listener;
 28     private int index = 1;
 29     private boolean isRefresh = true;
 30     private String jjNetype;
 31 
 32     final static int DRAWITHCOURSE = 1;
 33     final static int DRAWITHEMPTY = 2;
 34     private Handler handler = new Handler() {
 35         public void handleMessage(Message msg) {
 36             switch (msg.what) {
 37                 case DRAWITHCOURSE:
 38                     m_listener.drawUIWithList(jjNetype);
 39                     if (isRefresh) {
 40                         list.clear();
 41                     }
 42                     list.addAll((List) msg.obj);
 43                     adapter.notifyDataSetChanged();
 44                     break;
 45 
 46                 case DRAWITHEMPTY:
 47                     m_listener.drawUIWithEmptyList(jjNetype);
 48                     break;
 49 
 50             }
 51         }
 52     };
 53 
 54 
 55     public List<T> getAdapterList() {
 56         return adapter.getList();
 57     }
 58 
 59     public void doUIAfternet(List list) {
 60         if (list == null || list.size() <= 0) {
 61             handler.sendEmptyMessage(DRAWITHEMPTY);
 62         } else {
 63             Message msg = new Message();
 64             msg.what = DRAWITHCOURSE;
 65             msg.obj = list;
 66             handler.sendMessage(msg);
 67         }
 68     }
 69 
 70     public interface INetRefreshListListener {
 71         void onItemClickListener(int position, String netype); //点击时处理逻辑
 72 
 73         void netList(int index, String netype); //获取第几页的数据
 74 
 75         void isEnd(String netype); //已经到了尾部
 76 
 77         int getDataTotalSize(String netype); //获取所有数据的数量
 78 
 79         void drawUIWithList(String netype); //网络有数据时，渲染UI
 80 
 81         void drawUIWithEmptyList(String netype);//网络无数据时，渲染UI
 82 
 83         Context getContext();  //获取上下文
 84 
 85         void setAdapterConvert(BaseViewHolder viewHolder, Object t, String jjNetype); //初始化adapter
 86 
 87         PullToRefreshListView onGetPullToRefreshListView(String netype); //获取UI级list
 88     }
 89 
 90     class ListAdapter extends MyBaseAdapter<T> {
 91 
 92         public ListAdapter(Context context, int resource, List<T> list) {
 93             super(context, resource, list);
 94         }
 95 
 96         @Override
 97         public void setConvert(BaseViewHolder viewHolder, T t) {
 98             m_listener.setAdapterConvert(viewHolder, t, jjNetype);
 99         }
100     }
101 
102     /**
103      * 构造函数：
104      * 1 netype: 网络URL
105      * 2 adapterres：adapter的资源id
106      * 3 INetRefreshListListener：监听器，用于获取activit相关信息
107      */
108     public NetRefreshListView(String netype, int adapterres, final INetRefreshListListener in_listener) {
109         try {
110             m_listener = in_listener;
111             listView = in_listener.onGetPullToRefreshListView(netype);
112 
113             Constructor cons = ListAdapter.class.getConstructor(NetRefreshListView.class, Context.class, int.class, List.class);
114             adapter = (ListAdapter) cons.newInstance(new Object[]{this, m_listener.getContext(), adapterres, list});
115 
116             jjNetype = netype;
117             listView.getRefreshableView().setAdapter(adapter);
118             listView.getRefreshableView().setOnItemClickListener(new AdapterView.OnItemClickListener() {
119                 @Override
120                 public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
121                     m_listener.onItemClickListener(position, jjNetype);
122                 }
123             });
124 
125             listView.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener() {
126                 @Override
127                 public void onRefresh() {
128                     if (listView.hasPullFromTop() || (!listView.hasPullFromTop() && m_listener.getDataTotalSize(jjNetype) <= 0)) {
129                         index = 1;
130                         isRefresh = true;
131                         m_listener.netList(index, jjNetype);
132                     } else {
133                         isRefresh = false;
134                         if (!next()) {
135                             listView.onRefreshComplete();
136                             m_listener.isEnd(jjNetype);
137                             return;
138                         }
139                         index++;
140                         m_listener.netList(index, jjNetype);
141                     }
142                     listView.onRefreshComplete();
143                 }
144             });
145         } catch (Exception e) {
146             Log.e("GXT", e.getMessage());
147         }
148     }
149 
150     public void refresh() {
151         index = 1;
152         isRefresh = true;
153         m_listener.netList(index, jjNetype);
154     }
155 
156 
157     private boolean next() {
158         if (list.size() < m_listener.getDataTotalSize(jjNetype)) {
159             return true;
160         } else {
161             return false;
162         }
163     }
164 
165 }

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posted on 2016-08-18 11:05 高子扬阅读(241) 评论(0) 编辑收藏举报