GridView 滑动到底部时加载新数据

首先是GridView监听Scoll事件，当到达底部是，做相应的操作。

具体的GridViewScoll事件，网络牛人已经写的很好了，转载地http://blog.csdn.net/hellogv/article/details/6615487

/**
 * @author admin
 * GridView 滑动监听器
 */
public class GridScrollListener implements OnScrollListener {

      /**
       * 到底部时回调函数
       */
      public interface AutoLoadCallBack {
        void execute();
      }

      private int getLastVisiblePosition = 0, lastVisiblePositionY = 0;
      private AutoLoadCallBack mCallback;

      public GridScrollListener(AutoLoadCallBack callback) {
        this.mCallback = callback;
      }

      public void onScrollStateChanged(AbsListView view, int scrollState) {

        if (scrollState == OnScrollListener.SCROLL_STATE_IDLE) {
          //滚动到底部   
          if (view.getLastVisiblePosition() == (view.getCount() - 1)) {
            View v = (View) view.getChildAt(view.getChildCount() - 1);
            int[] location = new int[2];
            v.getLocationOnScreen(location);//获取在整个屏幕内的绝对坐标
            int y = location[1];

            //MyLog.d("x" + location[0], "y" + location[1]);
            if (view.getLastVisiblePosition() != getLastVisiblePosition && lastVisiblePositionY != y)//第一次拖至底部     
            {
              Toast.makeText(view.getContext(), "已经拖动至底部，再次拖动即可翻页", 500).show();
              getLastVisiblePosition = view.getLastVisiblePosition();
              lastVisiblePositionY = y;
             
              return;
            } else if (view.getLastVisiblePosition() == getLastVisiblePosition && lastVisiblePositionY == y)//第二次托至底部    
            {
              mCallback.execute();
            }
          }

          //未滚动到底部，第二次托至底部都初始化
          getLastVisiblePosition = 0;
          lastVisiblePositionY = 0;
        }
      }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem,
            int visibleItemCount, int totalItemCount) {
        // TODO Auto-generated method stub
        
    }
    
    


    }

然后是在到达底部时根据回调函数来进行添加新数据

/**
 * @author admin 
 */
public class GoodsShowView implements InitLayoutI {
    private static String TAG = "GoodsView";
    private View mView;
    private Activity mActivity;
    private GridView gridview;
    private LinearLayout myLayout;
    private LinearLayout _layout;
    private LayoutInflater inflater;
    private GoodsInfo goodsInfo;
    private static int NumColumns = 2;

    private List<GoodsInfo> goodsList;

    public GoodsShowView(View view, Activity activity, LinearLayout layout) {
        // TODO Auto-generated constructor stub
        this.mView = view;
        this.mActivity = activity;
        inflater = LayoutInflater.from(mActivity);
        this.myLayout = layout;
        initLayout();
    }

    @Override
    public void initLayout() {
        // TODO Auto-generated method stub
        System.out.println(TAG + "-----" + "1");
        View _view = inflater.inflate(R.layout.goods_show_layout, null);
        _layout = (LinearLayout) _view.findViewById(R.id.goods_show_layoutID);
        initWidget();
        myLayout.removeAllViews();
        myLayout.addView(_layout);

    }

    @Override
    public void initWidget() {
        // TODO Auto-generated method stub
        
        /* 九宫格 */
        gridview = (GridView) _layout.findViewById(R.id.MainActivityGrid);
        goodsList = getData();
        MyGridAdapter adapter = new MyGridAdapter(goodsList, mActivity);
    
        gridview.setAdapter(adapter);
        gridview.setNumColumns(NumColumns);
        gridview.setOnItemClickListener(new gridViewOnClick());
        GridScrollListener autoLoadListener = new GridScrollListener(callBack);
        gridview.setOnScrollListener(autoLoadListener);
    }

    @Override
    public Object initData() {
        return goodsInfo;
        // TODO Auto-generated method stub
    }

    private List<GoodsInfo> getData() {
        System.out.println(TAG + "--------加载数据");
        List<GoodsInfo> list = new ArrayList<GoodsInfo>();
        for (int i = 0; i < 10; i += 1) {
            goodsInfo = new GoodsInfo();
            Random random = new Random(10000);
            goodsInfo.setGoodsName("物品");
            goodsInfo.setGoodsPrice(10000);
            goodsInfo.setGoodsInfos("物美价廉");
            // goodsInfo.setGoodsImage(R.drawable.small);
            list.add(goodsInfo);
        }
        return list;
    }

    /**
     * 翻页下页数据
     */
    private void getNextData() {
        // TODO Auto-generated method stub
        ListAdapter la = gridview.getAdapter();
                //新数据源
        List<GoodsInfo> list = new ArrayList<GoodsInfo>();
        for (int i = 0; i < 10; i += 1) {
            goodsInfo = new GoodsInfo();
            Random random = new Random(10000);
            goodsInfo.setGoodsName("物品");
            goodsInfo.setGoodsPrice(500);
            goodsInfo.setGoodsInfos("物美价廉");
            
                       //注意！添加到原先适配器的List
            goodsList.add(goodsInfo); 
        }
                 //核心！通知GridView适配器 数据改变
        ((MyGridAdapter) la).notifyDataSetChanged();
    }

    private class BtnOnclick implements OnClickListener {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Toast.makeText(mActivity, "点击" + 0, 0).show();
        }
    }

    private class gridViewOnClick implements OnItemClickListener {
        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                long arg3) {
            // TODO Auto-generated method stub
            int index = arg2 + 1;
            Toast.makeText(mActivity, "点击" + index, 0).show();
            Intent intent = new Intent();
            intent.setClass(mActivity, GoodsActivity.class);
            mActivity.startActivity(intent);
        }

    }

    /**
     * 回调函数
     */
    AutoLoadCallBack callBack = new AutoLoadCallBack() {

        public void execute() {
            Toast.makeText(mActivity, "滚动至底部", 500).show();
            getNextData();
        }

    };

}