强制关闭，使用asynctask下载文件

Question

我有一个正在运行的下载功能。但是当我运行它时，如80％的时间让我的手机变得迟缓，强行关闭，而不是像1〜2分钟那样长时间响应。这个案件发生得非常随机，我真的无法追查到底是什么问题。下载完成后，设备将恢复正常。我曾尝试过各种设备，如星系S2，星系笔记，SE xperia Arc S和几张桌子。问题依然存在。任何人都可以告诉我如何提高我的代码？下面是我现有的代码：

public void onClickDownload(View view){ 
     String url = "http://www.mydomain.com./" + fileURL; 
     url = url.replaceAll(" ","%20"); 
     String sourceUrl = url; 
     new DownloadFileAsync().execute(sourceUrl); 
    } 

public class DownloadFileAsync extends AsyncTask<String, Integer, Void> { 
     private boolean run_do_in_background = true; 

    @Override 
    protected void onPreExecute(){ 
     super.onPreExecute(); 
     } 

    @Override 
    protected Void doInBackground(String... aurl) { 
     int count; 
     try { 
      URL url = new URL(aurl[0]); 
      URLConnection conexion = url.openConnection(); 
      conexion.connect(); 

      int lengthOfFile = conexion.getContentLength(); 
      Log.d("ANDRO_ASYNC", "Lenght of file: " + lengthOfFile); 

      File folder = new File(Environment.getExternalStorageDirectory() + "/MaxApps"); 
      boolean success = false; 
      if (!folder.exists()) { 
       success = folder.mkdirs(); 
      } 
      if (!success) { 
      } else { 
      } 

      InputStream input = new BufferedInputStream(url.openStream()); 
      OutputStream output = new FileOutputStream("/sdcard/MaxApps/" + apkURL); 

      byte data[] = new byte[100*1024]; 

      long total = 0; 

      while ((count = input.read(data)) != -1) { 
      total += count;    
      int progressPercent = (int) ((total*100)/lengthOfFile); 
      if(progressPercent % 5 == 0){ 
       publishProgress(progressPercent); 
       } 
      output.write(data, 0, count); 
      } 

      output.flush(); 
      output.close(); 
      input.close(); 
      } catch (Exception e) { 

       notificationManager.cancel(Integer.parseInt(ID.toString())); 

       Notification MyN = new Notification(); MyN.icon = R.drawable.logo1; 
       MyN.tickerText = "Download Failed"; 
       MyN.number = 1; 
       MyN.setLatestEventInfo (getApplicationContext(), apkURL + " Download Failed.", "Please try again", MyPI); 
       MyN.flags |= Notification.FLAG_AUTO_CANCEL; 
       MyNM.notify(1, MyN);  
       run_do_in_background = false; 
      } 

     return null; 
    } 

    @Override 
    protected void onProgressUpdate(Integer... progress) {   
     notification.contentView.setProgressBar(R.id.pbStatus, 100, progress[0], false); 
     notificationManager.notify(Integer.parseInt(ID.toString()), notification); 
     } 

    @Override 
    protected void onPostExecute(Void unused) { 
     if(run_do_in_background) { 
     notificationManager.cancel(Integer.parseInt(ID.toString())); 

     Notification MyN = new Notification(); MyN.icon = R.drawable.logo1; 
     MyN.tickerText = "Download Complete"; 
     MyN.number = 1; 
     MyN.setLatestEventInfo (getApplicationContext(), "Download Complete, Click to install.", apkURL, MyPI); 
     MyN.flags |= Notification.FLAG_AUTO_CANCEL; 
     MyNM.notify(Integer.parseInt(ID.toString()) , MyN); 
     } 
    } 
} 

Answer 1

这可能是更新的UI花了很长时间？也许你可以尝试测试这样，看看它是否有差别：

@Override 
protected void onProgressUpdate(Integer... progress) {   
    Log.d("ANDRO_ASYNC", "Progress: " + progress[0]); 
} 

顺便说一句，这是不相关的，你问什么，但我认为你有一个处理的进展情况在你的代码的问题：

int progressPercent = (int) ((total*100)/lengthOfFile); 
if(progressPercent % 5 == 0){ 
    publishProgress(progressPercent); 
} 

，只有当它是完全5,10,15,20％等将更新的进展...我猜你真正想要更新的进展时，它至少是5％，进一步比以前。

int previousProgress = 0; 
while ((count = input.read(data)) != -1) { 
    total += count;    
    int progressPercent = (int) ((total*100)/lengthOfFile); 
    if(progressPercent - previousProgress >= 5) { 
     previousProgress = progressPercent; 
     publishProgress(progressPercent); 
    } 
    output.write(data, 0, count); 
}