Android-ListView图像在滚动时被洗牌

我正在尝试使用动态加载的图像创建ListView，使用AsyncTask下载图像，然后将其设置到ListView中。我的问题是，当向下滚动时，图像会被随机更改

public class GetAllCustomerListViewAdapter extends BaseAdapter {

private JSONArray dataArray;
private Activity activity;

private static LayoutInflater inflater = null;
private static final String baseUrlForImage = "http://192.168.254.1/contact/images/";

public GetAllCustomerListViewAdapter(JSONArray jsonArray, Activity a)
{
    this.dataArray = jsonArray;
    this.activity = a;


    inflater = (LayoutInflater) this.activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public int getCount() {
    return this.dataArray.length();
}

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

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

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

    // set up convert view if it is null
    final ListCell cell;
    if (convertView == null)
    {
        convertView = inflater.inflate(R.layout.get_all_customer_list_view_cell, null);
        cell = new ListCell();

        cell.FullName = (TextView) convertView.findViewById(R.id.customer_full_name);
        cell.Age = (TextView) convertView.findViewById(R.id.customer_age);

        cell.mobile = (ImageView) convertView.findViewById(R.id.customer_mobile);

        convertView.setTag(cell);
    }
    else
    {
        cell = (ListCell) convertView.getTag();
    }

    // change the data of cell

    try
    {
        JSONObject jsonObject = this.dataArray.getJSONObject(position);
        cell.FullName.setText(jsonObject.getString("FirstName")+" "+jsonObject.getString("LastName"));
        cell.Age.setText(" "+jsonObject.getInt("Age"));

        String nameOfImage = jsonObject.getString("id");

        String urlForImageInServer = "http://192.168.254.1/contact/getImage.php?id="+nameOfImage;

        new AsyncTask<String, Void, Bitmap>() {

            @Override
            protected Bitmap doInBackground(String... params) {
                String url = params[0];
                Bitmap icon = null;

                try {
                    InputStream in = new java.net.URL(url).openStream();
                    icon = BitmapFactory.decodeStream(in);
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

                return icon;
            }

            protected void onPostExecute(Bitmap result) {
                cell.mobile.setImageBitmap(result);             
            }               


        }.execute(urlForImageInServer);           



    }
    catch (JSONException e)
    {
        e.printStackTrace();
    }


    return convertView;
}



private  class  ListCell
{
    private TextView FullName;
    private TextView Age;

    private ImageView mobile;

}    

公共类GetAllCustomerListViewAdapter扩展BaseAdapter{
私有JSONArray数据阵列；
私人活动；
专用静态充气机=空；
私有静态最终字符串baseUrlForImage=”http://192.168.254.1/contact/images/";
公共GetAllCustomerListViewAdapter（JSONArray JSONArray，活动a）
{
this.dataArray=jsonArray；
本活动=a；
充气器=（LayoutFlater）this.activity.getSystemService（Context.LAYOUT\u充气器\u服务）；
}
@凌驾
public int getCount（）{
返回此.dataArray.length（）；
}
@凌驾
公共对象getItem（int位置）{
返回位置；
}
@凌驾
公共长getItemId（int位置）{
返回位置；
}
@凌驾
公共视图getView（int位置、视图转换视图、视图组父视图）{
//设置转换视图（如果为空）
最终列表细胞；
if（convertView==null）
{
convertView=充气机。充气（R.layout.get\u all\u customer\u list\u view\u cell，空）；
cell=新的ListCell（）；
cell.FullName=（TextView）convertView.findViewById（R.id.customer\u full\u name）；
cell.Age=（TextView）convertView.findViewById（R.id.customer\u Age）；
cell.mobile=（ImageView）convertView.findViewById（R.id.customer\u mobile）；
convertView.setTag（单元格）；
}
其他的
{
cell=（ListCell）convertView.getTag（）；
}
//更改单元格的数据
尝试
{
JSONObject JSONObject=this.dataArray.getJSONObject（位置）；
cell.FullName.setText（jsonObject.getString（“FirstName”）+“”+jsonObject.getString（“LastName”）；
cell.Age.setText（“+jsonObject.getInt”（“Age”）；
字符串nameOfImage=jsonObject.getString（“id”）；
字符串urlForImageInServer=”http://192.168.254.1/contact/getImage.php?id=“+图像名称；
新建异步任务（）{
@凌驾
受保护位图doInBackground（字符串…参数）{
字符串url=params[0]；
位图图标=空；
试一试{
InputStream in=new java.net.URL（URL.openStream（）；
icon=BitmapFactory.decodeStream（in）；
}捕获（IOE异常）{
//TODO自动生成的捕捉块
e、 printStackTrace（）；
}
返回图标；
}
受保护的void onPostExecute（位图结果）{
cell.mobile.setImageBitmap（结果）；
}               
}.execute（urlForImageInServer）；
}
捕获（JSONException e）
{
e、 printStackTrace（）；
}
返回视图；
}
私有类列表单元
{
私有文本视图全名；
私人文本浏览年龄；
私用ImageView手机；
}    

}

我最近才这么做（实际上是凌晨1点）——问题是ListView正在积极地回收视图。因此，它会得到仍然保存位图的旧视图

以下是您需要的：

[注意：检查位图是否已提前缓存。如果未缓存，请执行以下步骤]

尝试加载位图之前，请先缓存位图

缓存目标图像视图（并跟踪位图与位图的匹配情况）。另外，清空ImageView，以防它仍然包含以前回收项目中的位图（

ImageView.setImageBitmap（null）；

）

仔细检查缓存的ImageView是否尚未缓存上一个项目。如果之前已经缓存，则以某种方式声明不应加载正在接收的位图（我通过为每个点存储ImageView来实现这一点，一旦接收到位图，如果该行的ImageView再次为空，则不加载位图）

加载位图（如上所述）如果仍然应该加载，即如果ImageView没有再次回收。正如我前面提到的

该解决方案虽然有点复杂，但如果正确实施，效果会非常好且顺利。如果您想要一个例子，请随时查看一个实际的例子

编辑请求的示例：

下面是一些不那么伪的伪代码。您仍然需要做的主要部分实际上是实现延迟加载系统（这是一个完全不同的主题）。再一次，请随意访问上面链接的我的项目，特别是查看

公共类GetAllCustomerListViewAdapter扩展BaseAdapter{
私有JSONArray数据阵列；
私人活动；
专用静态充气机=空；
私有静态最终字符串baseUrlForImage=”http://192.168.254.1/contact/images/";
//该列表按行的顺序缓存位图和目标图像视图
私有ArrayList rowViewDataList；
公共GetAllCustomerListViewAdapter（JSONArray JSONArray，活动a）
{
this.dataArray=jsonArray；
本活动=a；
充气器=（LayoutFlater）this.activity.getSystemService（Context.LAYOUT\u充气器\u服务）；
//初始化列表
rowViewDataList=newArrayList（dataArray.length（））；
//这更像是一个首选项，但是为rowViewDataList添加每个项目
对于（int i=0；ipublic class GetAllCustomerListViewAdapter extends BaseAdapter {

    private JSONArray dataArray;
    private Activity activity;

    private static LayoutInflater inflater = null;
    private static final String baseUrlForImage = "http://192.168.254.1/contact/images/";

    // The list caches bitmaps as well as target imageViews, in order of the rows
    private ArrayList<RowViewData> rowViewDataList;

    public GetAllCustomerListViewAdapter(JSONArray jsonArray, Activity a)
    {
        this.dataArray = jsonArray;
        this.activity = a;


        inflater = (LayoutInflater) this.activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        // Initialize the list
        rowViewDataList = new ArrayList<RowViewData>(dataArray.length());

        // This is more of a preference, but add in every item for the rowViewDataList
        for(int i = 0; i < dataArray.length(); ++i) {
            // Create a new, empty rowViewData instance and put it into the list
            RowViewData rowData = new RowViewData();
            rowViewDataList.add(rowData);
        }
    }

    @Override
    public int getCount() {
        return this.dataArray.length();
    }

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

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

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

        // set up convert view if it is null
        final ListCell cell;
        if (convertView == null)
        {
            convertView = inflater.inflate(R.layout.get_all_customer_list_view_cell, null);
            cell = new ListCell();

            cell.FullName = (TextView) convertView.findViewById(R.id.customer_full_name);
            cell.Age = (TextView) convertView.findViewById(R.id.customer_age);

            cell.mobile = (ImageView) convertView.findViewById(R.id.customer_mobile);

            convertView.setTag(cell);
        }
        else
        {
            cell = (ListCell) convertView.getTag();
        }

        // change the data of cell

        try
        {
            JSONObject jsonObject = this.dataArray.getJSONObject(position);
            cell.FullName.setText(jsonObject.getString("FirstName")+" "+jsonObject.getString("LastName"));
            cell.Age.setText(" "+jsonObject.getInt("Age"));


            // Get the rowViewData for this position
            RowViewData curRowViewData = rowViewDataList.get(position);

            // If the bitmap is already cached, just use it
            if(curRowViewData.bitmap != null) {
                cell.mobile.setImageBitmap(curRowViewData.bitmap);
            }
            // Otherwise, gotta do some real work
            else {
                // First, set the cell's imageView's bitmap to null
                //      [in case this is a recycled view already with a bitmap]
                cell.mobile.setImageBitmap(null);

                // Then, start up the caching system
                String nameOfImage = jsonObject.getString("id");
                String urlForImageInServer = "http://192.168.254.1/contact/getImage.php?id="+nameOfImage;

                // Create a system to load images lazily and then receive the bitmaps
                // Look at my ImageLoaderNoCache for an example. Feel free to reuse it
                /**
                 * this = this adapter should implement an interface. Look below for the corresponding method
                 * url = image source url
                 * position = position this bitmap belongs to. Will get returned along with bitmap for reference
                 */
                LazyImageLoader.GetBitmap(this, url, position);

                // Cache/target this imageView for later
                curRowViewData.targetImageView = cell.mobile;

                // Double check this imageView is not being targeted already elsewhere
                //      ie, one of the recycling fixes [else, two bitmaps would load at once, etc]
                //  Also, probably could be more efficient
                for(int i = 0; i < rowViewDataList.size(); ++i) {
                    // If this is the current position, then skip all the logic for this round
                    if(i == position) continue;

                    // Get the rowViewData for this round
                        // Yeah... I should've used "cell" instead of row for you...
                    RowViewData checkRowData = rowViewDataList.get(i);

                    // If the targeted ImageView is the same, null-ify it
                    if(checkRowData.targetImageView == curRowViewData.targetImageView) {
                        // The old one should be null as the bitmap should not load suddenly into
                        //      the current recycled item
                        checkRowData.targetImageView = null;

                        // Personally, I knew that there would only be one copy at any time
                        //      so I tried to save time by breaking out here. Feel free to be
                        //          cautious and comment out the break statement
                        break;
                    }
                }
            }
        }
        catch (JSONException e)
        {
            e.printStackTrace();
        }


        return convertView;
    }

    /**
     * Should be called as part of an interface with the LazyImageLoader
     * @param bitmap - The lazily loaded bitmap that was requested earlier
     * @param position - The row/cell position that the bitmap was requested for
     */
    public void getBitmapForPosition(Bitmap bitmap, int position) {
        // Get the rowViewData instance for this row/position
        RowViewData curRowData = rowViewDataList.get(position);

        // Cache the bitmap
        curRowData.bitmap = bitmap;

        // Check if the bitmap should be loaded still
        if(curRowData.targetImageView != null) {
            curRowData.targetImageView.setImageBitmap(bitmap);

            // Not sure if strictly necessary, but good practice to make the cached view null now
            curRowData.targetImageView = null;
        }
    }

    private  class  ListCell
    {
        private TextView FullName;
        private TextView Age;

        private ImageView mobile;

    }

    // Holds all the data for lazily loading an image with a bitmap
    private class RowViewData {
        public ImageView targetImageView;
        public Bitmap bitmap;
    }
}