Question

在我的应用中，我在每个列表行中都使用了上传Button和Progressbar，我也能够将图像上传到服务器，但是每当我点击时都会面临一个小问题在列表项的上传按钮上，它总是在最后一个列表项行显示Progressbar，这是可见的......为什么？

然而必须在同一行显示Progressbar，我要为其上传图片...

例如：我在列表中有3个图像，即03.jpg，02.jpg和01.jpg，所以每当我点击03.jpg或02.jpg或01.jpg的上传按钮时，每次我我在01.jpg排上获得进度条！

并且在我的列表中只能看到三条记录，以查看更多需要滚动...

    ViewHolder holder ;
    View v ;

        /*** Get Images from SDCard ***/
        ImageList = getSD();

        // ListView and imageAdapter
        lstView = (ListView) findViewById(R.id.listView1);
        lstView.setAdapter(new ImageAdapter(this)); 
        }

        public static List <String> getSD()
        {
            List <String> it = new ArrayList <String>();
            String string = "/mnt/sdcard/Pictures/SamCam/";
            f = new File (string+ CameraLauncherActivity.folder+ "/");
            files = f.listFiles ();

            /***
             * to show last taken image on top using lastModified
             * to sort data
             * to refresh data after (remove or update)
             */
            Arrays.sort(files, new Comparator<Object>()
            {
                public int compare(Object o1, Object o2) {

                    if (((File)o1).lastModified() > ((File)o2).lastModified()) {
                        return -1;
                    } else if (((File)o1).lastModified() < ((File)o2).lastModified()) {
                        return +1;
                    } else {
                        return 0;
                    }
                }
            });
            // <<<<<<<<< END >>>>>>>>>>>

            for (int i = 0; i < files.length; i++)
            {
            file = files[i];
            Log.d("Count",file.getPath());
            it.add (file.getPath());
            }

        return it;  
        }

  public View getView(final int position, View convertView, ViewGroup parent) {
            // Avoid unneccessary calls to findViewById() on each row, which is expensive!
            holder = null;

                // If this item is to be synced
                if(flags.get(position)) {
                    startUpload(position);

                // Mark as synced
                flags.put(position, false);
                }
 if (convertView == null) {
                convertView = getLayoutInflater().inflate(R.layout.list_upload, null);
                holder = new ViewHolder(convertView);

 holder.uploadProgressBar = (ProgressBar) convertView.findViewById(R.id.progressBar);
    convertView.setTag(holder);
                } else {

                    holder = (ViewHolder) convertView.getTag();
                }
holder.uploadProgressBar.setVisibility(View.GONE);

                 ..................................

                    // btnUpload
                    holder.uploadImageButton.setOnClickListener(new View.OnClickListener() {
                    public void onClick(View v) {
                    // Upload
                            startUpload(position);
                        }
                    });
                   return convertView;

                  } 
              }

        //Upload
        public void startUpload(final int position) {      

            Runnable runnable = new Runnable() {

            public void run() {

                handler.post(new Runnable() {

            public void run() {

                v = lstView.getChildAt(position - lstView.getFirstVisiblePosition());

                holder.uploadProgressBar.setVisibility(View.VISIBLE);

                holder.statusImageView.setImageResource(R.drawable.bullet_button);

                    new UploadFileAsync().execute(String.valueOf(position));   
                            }
                        });
                    }
                };
                new Thread(runnable).start();
                }

Answer 1

看起来你在startUpload中使用runnable中的holder变量，但是你永远不会初始化它，所以基本上你正在重用分配给{的最后一个ViewHolder实例{1}}变量。尝试这样的事情：

holder

Answer 2

你在哪里发起

 holder.uploadProgressBar?

我认为

 position

是你的问题..

你总是得到最后一项进度条，因为你的

 position

始终是最后一个项目的位置。你需要发起

 uploadProgress

内

(if (convertView == null) {}) method

让每个人都进行回收

 getView

迭代..

您可以使用我的代码作为参考：

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    final Sub_Category sub_category = getItem(position);
    ViewHolder holder;

    if (convertView == null) {
        //create new view
        convertView = LayoutInflater.from(getContext()).inflate(R.layout.hit_me_sub_row,parent,false);
        holder = new ViewHolder();
        holder.uploadProgressBar = (ProgressBar) convertView.findViewById(R.id.progressBar);
        convertView.setTag(holder);

    } else {
        holder = (ViewHolder) convertView.getTag();
    }


if(SOME CONDITION)
                holder.uploadProgressBar .setVisibility(8);
            else if(OTHER CONDITION)
            {
                holder.uploadProgressBar .setVisibility(8);
            }
  return convertView;
}

Answer 3

尝试使用Tag for按钮，如下所示。

holder.uploadImageButton.setTag(position); //add this line
holder.uploadImageButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            // Upload
             startUpload((Integer)holder.uploadImageButton.getTag()); //change this line
                                OR  
             startUpload((Integer)v.getTag()); //change this line
             }
        });

在列表行中显示进度条

3 个答案: