ListView封装实现下拉刷新和上拉加载(方式2)（转载）

转自：http://blog.csdn.net/jdfkldjlkjdl/article/details/70229465

这次使用的是系统的SwipeRefreshLayout实现下拉刷新，和设置ListView的滑动监听判断是否滑动到最底部然后加载更多；如果想了解用另一种方式实现这个功能，请移步http://blog.csdn.net/jdfkldjlkjdl/article/details/51277941

其中，SwipeRefreshLayout的几个方法功能如下:

1、setOnRefreshListener():设置手势滑动监听器。
2、setProgressBackgroundColor():设置进度圈的背景色。
3、setColorSchemeResources():设置进度动画的颜色。
4、setRefreshing():设置组件的刷洗状态。
5、setSize():设置进度圈的大小

下面说一下实现步骤:

1.添加布局文件

<android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/mSwipeRefreshLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <ListView
            android:id="@+id/mListView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:divider="#cccccc"
            android:dividerHeight="1px"/>
    </android.support.v4.widget.SwipeRefreshLayout>

2.添加加载更多的布局文件load_more.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:id="@+id/ll_load_more"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:orientation="vertical">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_margin="10dip"
        android:gravity="center_vertical"
        android:orientation="horizontal">

        <ProgressBar
            android:layout_width="30dp"
            android:layout_height="30dp"
            android:layout_gravity="center"
            />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dip"
            android:text="加载更多"
            android:textColor="#bbb"
            android:textSize="12sp"/>
    </LinearLayout>

</LinearLayout>

3.绑定下拉刷新事件

//设置手势监听
       mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
           @Override
           public void onRefresh() {
               mHandler.sendEmptyMessageDelayed(REFRESH, 2000);
           }
       });

4.绑定上拉加载更多事件

//给listview设置一个滑动的监听
       mListView.setOnScrollListener(new AbsListView.OnScrollListener() {
           int visibleLastIndex = 0;    //最后的可视项索引
           int visibleItemCount;        // 当前窗口可见项总数

           //当滑动状态发生改变的时候执行
           public void onScrollStateChanged(AbsListView view, int scrollState) {
               switch (scrollState) {
                   //当不滚动的时候
                   case AbsListView.OnScrollListener.SCROLL_STATE_IDLE:
                       int itemsLastIndex = adapter.getCount() - 1;    //数据集最后一项的索引
                       int lastIndex = itemsLastIndex + 1;                //加上底部的loadMoreView项
                       //判断是否是最底部
                        //if (view.getLastVisiblePosition() == (view.getCount()) - 1) { //或者
                       if (visibleLastIndex == lastIndex) {
                           loadMoreView.setVisibility(View.VISIBLE);
                           mHandler.postDelayed(new Runnable() {
                               @Override
                               public void run() {
                                   //加载网络数据
                                   Message msg = new Message();
                                   msg.what = LOADMORE;
                                   msg.arg1 = visibleLastIndex - visibleItemCount + 1;
                                   mHandler.sendMessage(msg);
                               }
                           }, 2000);
                       }
                       break;
               }
           }

           //正在滑动的时候执行
           public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
               this.visibleItemCount = visibleItemCount;
               visibleLastIndex = firstVisibleItem + visibleItemCount - 1;
           }
       });

完整的activity代码如下:

package demo.xzy.qh.com.listviewpulltorefreshandloadmore;

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.widget.SwipeRefreshLayout;
import android.view.View;
import android.widget.AbsListView;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.List;

/**
 * ListView下拉刷新，上拉加载demo
 */
public class MainActivity extends Activity {
    private SwipeRefreshLayout mSwipeRefreshLayout;
    private ListView mListView;
    private List<String> data = new ArrayList<>();
    private ArrayAdapter<String> adapter;
    private static final int REFRESH = 0x01;
    private static final int LOADMORE = 0x02;
    private View loadMoreView;
    private Handler mHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            switch (msg.what) {
                case REFRESH:
                    data.add(0, "刷新得到的数据");
                    adapter.notifyDataSetChanged();
                    mSwipeRefreshLayout.setRefreshing(false);
                    break;
                case LOADMORE:
                    for (int x = 0; x < 5; x++) {
                        data.add(data.size(), "aaaaaa" + x);
                    }
                    adapter.notifyDataSetChanged();    //数据集变化后,通知adapter
                    int position = msg.arg1;
                    mListView.setSelection(position);    //设置选中项
                    loadMoreView.setVisibility(View.GONE);
                    break;
            }
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        for (int i = 0; i < 6; i++) {
            data.add("测试数据" + i);
        }

        initView();
    }

    private void initView() {
        mSwipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.mSwipeRefreshLayout);
        mListView = (ListView) findViewById(R.id.mListView);
        loadMoreView = getLayoutInflater().inflate(R.layout.load_more, null);

        loadMoreView.setVisibility(View.GONE);
        mListView.addFooterView(loadMoreView);
        mListView.setFooterDividersEnabled(false);

        //设置进度圈的大小;(这里面只有两个值SwipeRefreshLayout.LARGE和DEFAULT，后者是默认效果)
        mSwipeRefreshLayout.setSize(SwipeRefreshLayout.DEFAULT);
        //设置进度圈的背景色。这里随便给他设置了一个颜色：浅绿色
        mSwipeRefreshLayout.setProgressBackgroundColorSchemeColor(Color.CYAN);
        //设置进度动画的颜色。这里面最多可以指定四个颜色，我这也是随机设置的，大家知道怎么用就可以了
        mSwipeRefreshLayout.setColorSchemeResources(android.R.color.holo_orange_dark
                , android.R.color.holo_blue_dark
                , android.R.color.holo_red_dark
                , android.R.color.widget_edittext_dark);

        adapter = new ArrayAdapter<>(MainActivity.this, android.R.layout.simple_list_item_1, data);
        mListView.setAdapter(adapter);

        //设置手势监听
        mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                mHandler.sendEmptyMessageDelayed(REFRESH, 2000);
            }
        });
        //给listview设置一个滑动的监听
        mListView.setOnScrollListener(new AbsListView.OnScrollListener() {
            int visibleLastIndex = 0;    //最后的可视项索引
            int visibleItemCount;        // 当前窗口可见项总数

            //当滑动状态发生改变的时候执行
            public void onScrollStateChanged(AbsListView view, int scrollState) {
                switch (scrollState) {
                    //当不滚动的时候
                    case AbsListView.OnScrollListener.SCROLL_STATE_IDLE:
                        int itemsLastIndex = adapter.getCount() - 1;    //数据集最后一项的索引
                        int lastIndex = itemsLastIndex + 1;                //加上底部的loadMoreView项
                        //判断是否是最底部
                         //if (view.getLastVisiblePosition() == (view.getCount()) - 1) { //或者
                        if (visibleLastIndex == lastIndex) {
                            loadMoreView.setVisibility(View.VISIBLE);
                            mHandler.postDelayed(new Runnable() {
                                @Override
                                public void run() {
                                    //加载网络数据
                                    Message msg = new Message();
                                    msg.what = LOADMORE;
                                    msg.arg1 = visibleLastIndex - visibleItemCount + 1;
                                    mHandler.sendMessage(msg);
                                }
                            }, 2000);
                        }
                        break;
                }
            }

            //正在滑动的时候执行
            public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
                this.visibleItemCount = visibleItemCount;
                visibleLastIndex = firstVisibleItem + visibleItemCount - 1;
            }
        });

    }
}

整个demo很简单，就两个布局文件和一个activity。

至此，标题中提到的功能已经实现。欢迎留言指正。