listView的分页滑动

1.         ListView分页加载实现思路

实现OnScrollListener 接口重写onScrollStateChanged 和onScroll方法，使用onscroll方法实现”滑动“后处理检查是否还有新的记录，如果有，调用 addFooterView，添加记录到adapter, adapter调用 notifyDataSetChanged 更新数据;如果没有记录了，把自定义的mFooterView去掉。使用onScrollStateChanged可以检测是否滚到最后一行且停止滚动然后执行加载。

[java] view plaincopyprint?
import android.app.ListActivity;  
import android.os.Bundle;  
import android.os.Handler;  
import android.view.Gravity;  
import android.view.View;  
import android.view.ViewGroup;  
import android.widget.AbsListView;  
import android.widget.BaseAdapter;  
import android.widget.ImageView;  
import android.widget.LinearLayout;  
import android.widget.ProgressBar;  
import android.widget.TextView;  
import android.widget.AbsListView.OnScrollListener;  
import android.widget.LinearLayout.LayoutParams;  
public class Test extends ListActivity implements OnScrollListener {  
    Aleph0 adapter = new Aleph0();  
    int lastItem = 0;  
    int mProgressStatus = 0;  
    private Handler mHandler = new Handler();  
    ProgressBar progressBar;  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
   LinearLayout searchLayout = new LinearLayout(this);  
   searchLayout.setOrientation(LinearLayout.HORIZONTAL);  
         progressBar = new ProgressBar(this);  
         progressBar.setPadding(0, 0, 15, 0);  
         searchLayout.addView(progressBar,new LinearLayout.LayoutParams(  
           LinearLayout.LayoutParams.WRAP_CONTENT,  
           LinearLayout.LayoutParams.WRAP_CONTENT  
         ));  
         TextView textView = new TextView(this);  
         textView.setText("加载中...");  
         textView.setGravity(Gravity.CENTER_VERTICAL);  
         searchLayout.addView(textView,new LinearLayout.LayoutParams(  
           LinearLayout.LayoutParams.FILL_PARENT,  
           LinearLayout.LayoutParams.FILL_PARENT  
         ));  
         searchLayout.setGravity(Gravity.CENTER);  
         LinearLayout loadingLayout = new LinearLayout(this);  
         loadingLayout.addView(searchLayout,new LinearLayout.LayoutParams(  
           LinearLayout.LayoutParams.WRAP_CONTENT,  
           LinearLayout.LayoutParams.WRAP_CONTENT  
         ));  
         loadingLayout.setGravity(Gravity.CENTER);  
        getListView().addFooterView(loadingLayout);  
        // Start lengthy operation in a background thread  
//        new Thread(new Runnable() {  
//            public void run() {  
//                while (mProgressStatus < 100) {  
//  
//                    // Update the progress bar  
//                    mHandler.post(new Runnable() {  
//                        public void run() {  
//                        progressBar.setProgress(mProgressStatus);  
//                        }  
//                    });  
//                }  
//            }  
//        }).start();  
        registerForContextMenu(getListView());  
        setListAdapter(adapter);  
        getListView().setOnScrollListener(this);  
    }  
    public void onScroll(AbsListView v, int firstVisibleItem, int visibleItemCount, int totalItemCount) {   
        lastItem = firstVisibleItem + visibleItemCount - 1 ;  
        System.out.println("lastItem:" + lastItem);  
    }  
    public void onScrollStateChanged(AbsListView v, int state) {  
    if(lastItem == adapter.count && state == OnScrollListener.SCROLL_STATE_IDLE){  
          adapter.count += 10;  
          adapter.notifyDataSetChanged();  
    }  
//        if(state == OnScrollListener.SCROLL_STATE_IDLE ) {  
//                adapter.count += 10;  
//                adapter.notifyDataSetChanged();  
//        }  
    }  
    class Aleph0 extends BaseAdapter {  
        int count = 10;  
        public int getCount() { return count; }  
        public Object getItem(int pos) { return pos; }  
        public long getItemId(int pos) { return pos; }  
        public View getView(int pos, View v, ViewGroup p) {  
                TextView view = new TextView(Test.this);  
                view.setText("entry " + pos);  
                view.setHeight(90);  
                return view;  
        }  
    }  
}  

第二种。

package com.notice.moredate;

import java.util.ArrayList;
import java.util.HashMap;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.SimpleAdapter;
import android.widget.Toast;

public class MoreDateListActivity extends Activity implements OnScrollListener {
    
    // ListView的Adapter
    private SimpleAdapter mSimpleAdapter;
    private ListView lv;
    private Button bt;
    private ProgressBar pg;
    private ArrayList<HashMap<String,String>> list;
    // ListView底部View
    private View moreView;
    private Handler handler;
    // 设置一个最大的数据条数，超过即不再加载
    private int MaxDateNum;
    // 最后可见条目的索引
    private int lastVisibleIndex;
    
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        
        MaxDateNum = 22; // 设置最大数据条数

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

        // 实例化底部布局
        moreView = getLayoutInflater().inflate(R.layout.moredate, null);

        bt = (Button) moreView.findViewById(R.id.bt_load);
        pg = (ProgressBar) moreView.findViewById(R.id.pg);
        handler = new Handler();

        // 用map来装载数据，初始化10条数据
        list = new ArrayList<HashMap<String,String>>();
        for (int i = 0; i < 10; i++) {
            HashMap<String, String> map = new HashMap<String, String>();
            map.put("ItemTitle", "第" + i + "行标题");
            map.put("ItemText", "第" + i + "行内容");
            list.add(map);
        }
        // 实例化SimpleAdapter
        mSimpleAdapter = new SimpleAdapter(this, list, R.layout.item,
                new String[] { "ItemTitle", "ItemText" },
                new int[] { R.id.tv_title, R.id.tv_content });
        // 加上底部View，注意要放在setAdapter方法前
        lv.addFooterView(moreView);
        lv.setAdapter(mSimpleAdapter);
        // 绑定监听器
        lv.setOnScrollListener(this);

        bt.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                pg.setVisibility(View.VISIBLE);// 将进度条可见
                bt.setVisibility(View.GONE);// 按钮不可见

                handler.postDelayed(new Runnable() {

                    @Override
                    public void run() {
                        loadMoreDate();// 加载更多数据
                        bt.setVisibility(View.VISIBLE);
                        pg.setVisibility(View.GONE);
                        mSimpleAdapter.notifyDataSetChanged();// 通知listView刷新数据
                    }

                }, 2000);
            }
        });

    }

    private void loadMoreDate() {
        int count = mSimpleAdapter.getCount();
        if (count + 5 < MaxDateNum) {
            // 每次加载5条
            for (int i = count; i < count + 5; i++) {
                HashMap<String, String> map = new HashMap<String, String>();
                map.put("ItemTitle", "新增第" + i + "行标题");
                map.put("ItemText", "新增第" + i + "行内容");
                list.add(map);
            }
        } else {
            // 数据已经不足5条
            for (int i = count; i < MaxDateNum; i++) {
                HashMap<String, String> map = new HashMap<String, String>();
                map.put("ItemTitle", "新增第" + i + "行标题");
                map.put("ItemText", "新增第" + i + "行内容");
                list.add(map);
            }
        }

    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem,
            int visibleItemCount, int totalItemCount) {
        // 计算最后可见条目的索引
        lastVisibleIndex = firstVisibleItem + visibleItemCount - 1;

        // 所有的条目已经和最大条数相等，则移除底部的View
        if (totalItemCount == MaxDateNum + 1) {
            lv.removeFooterView(moreView);
            Toast.makeText(this, "数据全部加载完成，没有更多数据！", Toast.LENGTH_LONG).show();
        }

    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        // 滑到底部后自动加载，判断listview已经停止滚动并且最后可视的条目等于adapter的条目
        if (scrollState == OnScrollListener.SCROLL_STATE_IDLE
                && lastVisibleIndex == mSimpleAdapter.getCount()) {
            // 当滑到底部时自动加载
            // pg.setVisibility(View.VISIBLE);
            // bt.setVisibility(View.GONE);
            // handler.postDelayed(new Runnable() {
            //
            // @Override
            // public void run() {
            // loadMoreDate();
            // bt.setVisibility(View.VISIBLE);
            // pg.setVisibility(View.GONE);
            // mSimpleAdapter.notifyDataSetChanged();
            // }
            //
            // }, 2000);

        }

    }
    
}