如何将url图像下载到现有的列表视图

Question

我有自己的基本适配器的自定义列表视图。它目前有一个标题和描述。编号喜欢从网址添加图片。但我不知道如何调整代码添加添加所述图像。

我已经在使用异步任务下载文件，当列表视图中的项目被按下时，我可以重复使用这种方法来添加图像吗？文件只在瞬间下载

我的异步任务

class DownloadFileFromURL extends AsyncTask<String, String, String> { 

    /** 
    * Before starting background thread 
    * Show Progress Bar Dialog 
    * */ 
    @Override 
    protected void onPreExecute() { 
     super.onPreExecute(); 
     showDialog(progress_bar_type); 
    } 

    /** 
    * Downloading file in background thread 
    * */ 
    @Override 
    protected String doInBackground(String... f_url) { 
     int count; 
     try { 
      URL url = new URL(f_url[0]); 
      URLConnection conection = url.openConnection(); 
      conection.connect(); 
      // getting file length 
      int lenghtOfFile = conection.getContentLength(); 

      // input stream to read file - with 8k buffer 
      InputStream input = new BufferedInputStream(url.openStream(), 8192); 

      // Output stream to write file 
      OutputStream output = new FileOutputStream("/sdcard/Download/"+newnamestring); 

      byte data[] = new byte[1024]; 

      long total = 0; 

      while ((count = input.read(data)) != -1) { 
       total += count; 
       // publishing the progress.... 
       // After this onProgressUpdate will be called 
       publishProgress(""+(int)((total*100)/lenghtOfFile)); 

       // writing data to file 
       output.write(data, 0, count); 
      } 

      // flushing output 
      output.flush(); 

      // closing streams 
      output.close(); 
      input.close(); 

     } catch (Exception e) { 
      Log.e("Error: ", e.getMessage()); 
     } 

     return null; 
    } 

    /** 
    * Updating progress bar 
    * */ 
    protected void onProgressUpdate(String... progress) { 
     // setting progress percentage 
     pDialog.setProgress(Integer.parseInt(progress[0])); 
    } 

    /** 
    * After completing background task 
    * Dismiss the progress dialog 
    * **/ 
    @Override 
    protected void onPostExecute(String file_url) { 
     // dismiss the dialog after the file was downloaded 

     dismissDialog(progress_bar_type); 
     Intent intent = new Intent(Intent.ACTION_VIEW); 
     intent.setDataAndType(Uri.fromFile(new File(Environment.getExternalStorageDirectory() + "/download/" + newnamestring)), "application/vnd.android.package-archive"); 
     intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
     startActivity(intent); 




    } 

} 

我的自定义基本适配器

class dataListAdapter extends BaseAdapter { 
    String[] Title, Detail; 


    dataListAdapter() { 
     Title = null; 
     Detail = null; 

     ; 

    } 

    public dataListAdapter(String[] text, String[] text1) { 
     Title = text; 
     Detail = text1; 





    } 

    public int getCount() { 
     // TODO Auto-generated method stub 
     return Title.length; 
    } 

    public Object getItem(int arg0) { 
     // TODO Auto-generated method stub 
     return null; 
    } 

    public long getItemId(int position) { 
     // TODO Auto-generated method stub 
     return position; 
    } 

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

     LayoutInflater inflater = getLayoutInflater(); 
     View row; 

     row = inflater.inflate(R.layout.custom, parent, false); 
     TextView title, detail; 
     title = (TextView) row.findViewById(R.id.titleapp); 
     detail = (TextView) row.findViewById(R.id.detail); 
     title.setText(Title[position]); 
     detail.setText(Detail[position]); 
     return (row); 
    } 


} 

Answer 1

，如果你想从URL下载图像，并显示

是到您的ImageView您可以将最好的东西做的就是使用Glide库，这个库可以下载Image并显示到你的imageView中，并将它缓存到另一个时间使用，这就是你在添加到你的项目后如何使用它的方法; Glide.with(mContext).load(imageUrl).into(yourImageView);