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Updating progress dialog

I am trying to make an application that can help me to evaluate the time to download the file from a web resource. I have found 2 samples:

Download a file with Android, and showing the progress in a ProgressDialog

and

http://www.helloandroid.com/tutorials/how-download-fileimage-url-your-device

The second example shows a smaller download time, but I cannot understand how to update progress dialog using it. I think something should be done with "while" expression in second case, but I cannot find what. Could someone give me any piece of advice?

UPD:

1st code:

try {
            time1 = System.currentTimeMillis();
            URL url = new URL(path);
            URLConnection conexion = url.openConnection();
            conexion.connect();
            // this will be useful so that you can show a tipical 0-100% progress bar
            int lenghtOfFile = conexion.getContentLength();
            // downlod the file
            InputStream input = new BufferedInputStream(url.openStream());
            OutputStream output = new FileOutpu开发者_Python百科tStream("/sdcard/analyzer/test.jpg");

            byte data[] = new byte[1024];

            long total = 0;

          time11 = System.currentTimeMillis();
           while ((count = input.read(data)) != -1) {
                total += count;
                // publishing the progress....
                publishProgress((int)(total*100/lenghtOfFile));
                output.write(data, 0, count);
            }
            time22= System.currentTimeMillis()-time11;
            output.flush();
            output.close();
            input.close();


        } catch (Exception e) {}

        timetaken = System.currentTimeMillis() - time1;

2nd code:

       long time1 = System.currentTimeMillis();
        DownloadFromUrl(path, "test.jpg");
        long timetaken = System.currentTimeMillis() - time1;

Where

  public void DownloadFromUrl(String imageURL, String fileName) {  //this is the downloader method
 try {
         URL url = new URL(imageURL); //you can write here any link
         File file = new File(fileName);

        /*Open a connection to that URL. */
         URLConnection ucon = url.openConnection();

         /*
          * Define InputStreams to read from the URLConnection.
          */
         InputStream is = ucon.getInputStream();
         BufferedInputStream bis = new BufferedInputStream(is);

         /*
          * Read bytes to the Buffer until there is nothing more to read(-1).
          */
         ByteArrayBuffer baf = new ByteArrayBuffer(50);
         int current = 0;
         while ((current = bis.read()) != -1) {
                 baf.append((byte) current);
         }

         /* Convert the Bytes read to a String. */
         FileOutputStream fos = new FileOutputStream(PATH+file);
         fos.write(baf.toByteArray());
         fos.close();

 } catch (IOException e) {
         Log.d("ImageManager", "Error: " + e);
 }

So the thing is that first method seems to be slower for about 30%.


The second example may run faster, but it monopolizes the GUI thread. The first approach, using AsyncTask, is better; it allows the GUI to stay responsive as the download proceeds.

I found it helpful to compare AsyncTask with SwingWorker, as shown in this example.


first link is best. But i can't provide code( it's home comp) in monday or later i can provide full function. But :

private class DownloadFile extends AsyncTask<String, Integer, String>{
    @Override
    protected String doInBackground(String... url) {
        int count;
        try {
            URL url = new URL(url[0]);
            URLConnection conexion = url.openConnection();
            conexion.connect();
            // this will be useful so that you can show a tipical 0-100% progress bar
            int lenghtOfFile = conexion.getContentLength();

            // downlod the file
            InputStream input = new BufferedInputStream(url.openStream());
            OutputStream output = new FileOutputStream("/sdcard/somewhere/nameofthefile.ext");

            byte data[] = new byte[1024];

            long total = 0;

            while ((count = input.read(data)) != -1) {
                total += count;
                // publishing the progress....
                publishProgress((int)(total*100/lenghtOfFile));
                output.write(data, 0, count);
            }

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

this class are best for it ( imho) . publishProgress it's simple function where u have max two lines. Set max and set current. How u can see in this code lenghtOfFile it's how many bytes have ur file. total-current progress ( example 25 from 100 bytes) . Run this class easy : DownloadFile a = new DownloadFile(); a.execute(value,value);//or null if u not using value. Hope u understand me , im not good speaking on english.

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