下拉刷新原理。

package com.lixu.listviewrefresh;

import java.util.ArrayList;

import android.app.Activity;
import android.os.Bundle;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class MainActivity extends Activity {
    private ArrayList<String> data;
    private ArrayAdapter<String> mMyAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        data = new ArrayList<String>();

        for (int i = 0; i < 30; i++) {
            data.add("测试数据" + i);
        }

        ListView lv = (ListView) findViewById(R.id.listview);

        mMyAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, data);

        lv.setAdapter(mMyAdapter);

        lv.setOnScrollListener(new OnScrollListener() {
            private int firstVisibleItem;
            private int visibleItemCount;
            private int totalItemCount;

            @Override
            public void onScrollStateChanged(AbsListView view, int scrollState) {
                // 当滑动停止的时候判断
                if (OnScrollListener.SCROLL_STATE_IDLE == scrollState) {

                    if (firstVisibleItem == 0) {

                        data.add(0, "增加头部数据" + (totalItemCount + 1));

                        mMyAdapter.notifyDataSetChanged();

                    }
                }

                if (OnScrollListener.SCROLL_STATE_IDLE == scrollState) {

                    if ((firstVisibleItem + visibleItemCount) == totalItemCount) {

                        data.add("增加尾部数据" + (totalItemCount + 1));

                        mMyAdapter.notifyDataSetChanged();

                    }
                }

            }

            @Override
            public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {

                this.firstVisibleItem = firstVisibleItem;
                this.visibleItemCount = visibleItemCount;
                this.totalItemCount = totalItemCount;

            }
        });

    }

}

效果图：