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How to use AsyncTask class to update the progress of copying a file another directory?

How should I be using AsyncTask class coupled with a progress bar to perform the copying process of a file to another directory in the local context of the phone sdcard? I have seen a simil开发者_运维问答ar example [here][1], but I have no idea how to incorporate the differences/modify the context of the code to suit my context to make it work?


It would be something like

// Params are input and output files, progress in Long size of 
// data transferred, Result is Boolean success.
public class MyTask extends AsyncTask<File,Long,Boolean> {
   ProgressDialog progress; 

  @Override
  protected void onPreExecute() {
    progress = ProgressDialog.show(ctx,"","Loading...",true);
  }

  @Override
  protected Boolean doInBackground(File... files) {
    copyFiles(files[0],files[1]);
    return true;
  }

  @Override
  protected void onPostExecute(Boolean success) {
    progress.dismiss();
    // Show dialog with result
  }

  @Override
  protected void onProgressUpdate(Long... values) {
    progress.setMessage("Transferred " + values[0] + " bytes");
  }
}

Now, inside copyFiles you will have to call publishProgress() with size of data transferred, for example. Note that progress generic parameter is Long. You can use CountingInputStream wrapper from commons-io for that.

There are number of additional things top take care of, but in the nutshell that is it.

To start:

  MyTask task = new MyTask();
  task.execute(src,dest);


Try using Async task as shown below:

 try{
    class test extends AsyncTask{


         TextView tv_per;
         int mprogress;

        Dialog UpdateDialog = new Dialog(ClassContext);

        @Override
        protected void onPreExecute() {
            // TODO Auto-generated method stub
            mprogress = 0;

            UpdateDialog.setTitle(getResources().getString(R.string.app_name));
            UpdateDialog.setContentView(R.layout.horizontalprogressdialog);
            TextView dialog_message =  (TextView)UpdateDialog.findViewById(R.id.titleTvLeft);
            tv_per = (TextView)UpdateDialog.findViewById(R.id.hpd_tv_percentage);
            dialog_message.setText(getResources().getString(R.string.dialog_retrieving_data));
            dialog_message.setGravity(Gravity.RIGHT);
            UpdateDialog.setCancelable(false);
            UpdateDialog.show();
            super.onPreExecute();
        }



        @Override
        protected void onProgressUpdate(Object... values) {
            // TODO Auto-generated method stub
            ProgressBar update = (ProgressBar)UpdateDialog.findViewById(R.id.horizontalProgressBar);
            update.setProgress((Integer) values[0]);
            int percent =  (Integer) values[0];
            if(percent>=100)
            {
                percent=100;
            }
            tv_per = (TextView)UpdateDialog.findViewById(R.id.hpd_tv_percentage);
             tv_per.setText(""+percent);
        }



        @Override
        protected Object doInBackground(Object... params) {
            // TODO Auto-generated method stub
            //your code
}

            super.onPostExecute(result);
            UpdateDialog.dismiss();
        }

     }
     new test().execute(null);

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