title: Android: How to work with background thread?
body: <p>I've developed an application that takes content from the internet and shows it accordingly on the device's screen . The program works just fine , a little bit slow . It takes about 3-4 seconds to load and display the content . I would like to put all the code that fetches the content and displays it in a background thread and while the program is doing those functions , I would like to display a progress dialog. Could you help me do this ? I would like especially to learn how to put the code in a background thread. </p>
  
  <p><strong>MY CODE</strong></p>
  
  <pre><code>public class Activity1 extends Activity
  {
      private ProgressDialog progressDialog;
  
      @Override
      public void onCreate(Bundle savedInstanceState)
      {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.main);
  
          new AsyncTask&lt;Integer, Integer, Boolean&gt;()
          {
              ProgressDialog progressDialog;
  
              @Override
              protected void onPreExecute()
              {
                  /*
                   * This is executed on UI thread before doInBackground(). It is
                   * the perfect place to show the progress dialog.
                   */
                  progressDialog = ProgressDialog.show(Activity1.this, "",
                          "Loading...");
              }
  
              @Override
              protected Boolean doInBackground(Integer... params)
              {
                  if (params == null)
                  {
                      return false;
                  }
                  try
                  {
                      /*
                       * This is run on a background thread, so we can sleep here
                       * or do whatever we want without blocking UI thread. A more
                       * advanced use would download chunks of fixed size and call
                       * publishProgress();
                       */
                      Thread.sleep(params[0]);
                      // HERE I'VE PUT ALL THE FUNCTIONS THAT WORK FOR ME
                  }
                  catch (Exception e)
                  {
                      Log.e("tag", e.getMessage());
                      /*
                       * The task failed
                       */
                      return false;
                  }
  
                  /*
                   * The task succeeded
                   */
                  return true;
              }
  
              @Override
              protected void onPostExecute(Boolean result)
              {
                  progressDialog.dismiss();
                  /*
                   * Update here your view objects with content from download. It
                   * is save to dismiss dialogs, update views, etc., since we are
                   * working on UI thread.
                   */
                  AlertDialog.Builder b = new AlertDialog.Builder(Activity1.this);
                  b.setTitle(android.R.string.dialog_alert_title);
                  if (result)
                  {
                      b.setMessage("Download succeeded");
                  }
                  else
                  {
                      b.setMessage("Download failed");
                  }
                  b.setPositiveButton(getString(android.R.string.ok),
                          new DialogInterface.OnClickListener()
                          {
  
                              @Override
                              public void onClick(DialogInterface dlg, int arg1)
                              {
                                  dlg.dismiss();
                              }
                          });
                  b.create().show();
              }
          }.execute(2000);
  
          new Thread()
          {
              @Override
              public void run()
              {
  
                  // dismiss the progressdialog
                  progressDialog.dismiss();
              }
          }.start();
      }
  }
  </code></pre>