LIstview滑动时不加载图片，停止时加载！

//参照 http://blog.csdn.net/yy1300326388/article/details/45153813 

public class CarWashDistanceAdapter extends BaseAdapter {
    private static final String TAG = "CarWashDistanceAdapter";
    private Context context;
    private MyDialog myDialog;
    private ArrayList<FourServiceBean> arrayList;
    private  boolean scrollState=false;
    private float density = 1.5f;
    //定义当前listview是否在滑动状态
    public void setScrollState(boolean scrollState) {
        this.scrollState = scrollState;
    }
    public CarWashDistanceAdapter(Context context, ArrayList<FourServiceBean> arrayList) {
        this.context = context;
        this.arrayList=arrayList;
    }
    public void refresh( ArrayList<FourServiceBean> arrayList) {
        this.arrayList=arrayList;
        notifyDataSetChanged();
    }
    @Override
    public int getCount() {
        return arrayList.size();
    }

    @Override
    public Object getItem(int position) {
        return arrayList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {

        Hodler hodler;
        if (convertView == null) {
            hodler = new Hodler();
            convertView = View.inflate(context, R.layout.listview_car_wash_item, null);
            hodler.mImageView = (ImageView) convertView.findViewById(R.id.car_wash_item_imageview);
            hodler.mTelImageview = (ImageView) convertView.findViewById(R.id.car_wash_item_phone_imageview);
            hodler.mTitleTextView = (TextView) convertView.findViewById(R.id.car_wash_item_title_textview);
            hodler.mDistanceTextView = (TextView) convertView.findViewById(R.id.car_wash_item_distance_textview);
            hodler.mSubTextView = (TextView) convertView.findViewById(R.id.car_wash_item_subtitle_textview);
            hodler.relativeLayout = (RelativeLayout) convertView.findViewById(R.id.car_wash_item_relativelayout);
            hodler.mRatingBar = (RatingBar) convertView.findViewById(R.id.car_wash_item_ratingbar);
            convertView.setTag(hodler);
        } else {
            hodler = (Hodler) convertView.getTag();

        }
        hodler.mTitleTextView.setText(arrayList.get(position).getShop_name());
        hodler.mSubTextView.setText(arrayList.get(position).getDetail_address());
        if(arrayList.get(position).getDistance()/1000 <= 1){
            hodler.mDistanceTextView.setText((new DecimalFormat("0").format(arrayList.get(position).getDistance()) + "m"));
        }else {

            hodler.mDistanceTextView.setText((new DecimalFormat("0.00").format(arrayList.get(position).getDistance()/1000)+ "km"));
        }
        if(arrayList.get(position).getScore()!=null  ) {
            hodler.mRatingBar.setRating(Float.valueOf(arrayList.get(position).getScore()));
        }

        final String[] sourceStrArray = arrayList.get(position).getTel_num_list().split(",");

        hodler.mTelImageview.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                myDialog = new MyDialog(context, R.style.MyDialog, new MyDialog.LeaveMyDialogListener() {
                    @Override
                    public void onClick(View view) {
                        switch (view.getId()) {
                            case R.id.mydialog_clear:
                                myDialog.dismiss();
                                break;

                        }
                    }
                }, Arrays.asList(sourceStrArray),myDialog);
                myDialog.show();
            }
        });
        //这获取的是图片的url
        String url = arrayList.get(position).getShop_pic_url();
        if (!scrollState){
            //如果当前不是滑动的状态，我们填充真数据
            //加载图片
            if(url!= null) {
                //这是我添加图片的方法
                THttpOpenHelper.newInstance().setImageBitmap(hodler.mImageView, url,(int)(100 * density), (int)(75 * density), R.drawable.icon_default1, R.drawable.icon_default1);
                //设置tag为1表示已加载过数据
                hodler.mImageView.setTag("1");
            }else{
                hodler.mImageView.setImageResource(R.drawable.icon_default1);
                hodler.mImageView.setTag("1");
            }
        }else{
            //如果当前是滑动的状态，我们填充假数据
            //将数据image_url保存在Tag当中
              hodler.mImageView.setTag(url);
                //设置默认显示图片（最好是本地资源的图片）
                hodler.mImageView.setImageResource(R.drawable.icon_default1);
          }
        return convertView;
    }

    private class Hodler {
        ImageView mImageView;
        ImageView mTelImageview;
        TextView mTitleTextView;
        TextView mSubTextView;
        TextView mDistanceTextView;
        RelativeLayout relativeLayout;
        RatingBar mRatingBar;
    }
}

以上是Adapter中的代码：其中重要的就是

  //定义当前listview是否在滑动状态
    public void setScrollState(boolean scrollState) {
        this.scrollState = scrollState;
    }

还有这段是给imageview赋值的操作

 //这获取的是图片的url
        String url = arrayList.get(position).getShop_pic_url();
        if (!scrollState){
            //如果当前不是滑动的状态，我们填充真数据
            //加载图片
            if(url!= null) {
                //这是我添加图片的方法
                THttpOpenHelper.newInstance().setImageBitmap(hodler.mImageView, url,(int)(100 * density), (int)(75 * density), R.drawable.icon_default1, R.drawable.icon_default1);
                //设置tag为1表示已加载过数据
                hodler.mImageView.setTag("1");
            }else{
                hodler.mImageView.setImageResource(R.drawable.icon_default1);
                hodler.mImageView.setTag("1");
            }
        }else{
            //如果当前是滑动的状态，我们填充假数据
            //将数据image_url保存在Tag当中
              hodler.mImageView.setTag(url);
                //设置默认显示图片（最好是本地资源的图片）
                hodler.mImageView.setImageResource(R.drawable.icon_default1);
          }

最后在Activity中添加

     mListView.setOnScrollListener(new AbsListView.OnScrollListener() {
                    @Override
                    public void onScrollStateChanged(AbsListView view, int scrollState) {
                        switch (scrollState){
                             //停止滚动
                            case AbsListView.OnScrollListener.SCROLL_STATE_IDLE:
                            {
                                //设置为停止滚动
                                carWashDistanceAdapter.setScrollState(false);
                                //当前屏幕中listview的子项的个数
                                int count = view.getChildCount();
                                for (int i = 0; i < count; i++) {
                                    //获取到item的图片显示的Imageview控件
                                    ImageView iv_show= (ImageView) view.getChildAt(i).findViewById(R.id.car_wash_item_imageview);
                                    if (!iv_show.getTag().equals("1")){//如果等于1说明图片资源已加载过，不等于说明没有去getTag()的图片url
                                      
                               //直接从Tag中取出我们存储的数据image——url
                                         String image_url = iv_show.getTag().toString();
                                         if (image_url != null) {//这个判断是防止图片的url是否为空，为空的话给默认图片。
                                             THttpOpenHelper.newInstance().setImageBitmap(iv_show, image_url, R.drawable.icon_default1, R.drawable.icon_default1);
                                             //设置为已加载过数据
                                             iv_show.setTag("1");
                                         } else {
                                             iv_show.setBackgroundResource(R.drawable.icon_default1);
                                             iv_show.setTag("1");
                                         }
                                    
                                    }
                                }
                                break;
                            }
                            //滚动做出了抛的动作
                            case AbsListView.OnScrollListener.SCROLL_STATE_FLING:
                            {
                                //设置为正在滚动
                                carWashDistanceAdapter.setScrollState(true);
                                break;
                            }
                             //正在滚动
                            case AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL:
                            {
                                //设置为正在滚动
                                carWashDistanceAdapter.setScrollState(true);
                                break;
                            }
                        }
                    }

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

                    }
                });