ListView封装实现下拉刷新和上拉加载(方式2)

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。