Progress Dialog in Android AsyncTask

I will show how to use ProgressDialog class for showing progress dialog to indicate page is loading in android.
Please try it your self.

package com.j4android;

import android.app.Activity;
import android.os.Bundle;

public class MainActicity extends Activity{
ProgressDialog progressBar;
@Override
public void onCreate(Bundle bundle){
super.onCreate(bundle);
setContentView(R.layout.main);

            progressBar = ProgressDialog.show(MainActicity.this, "","Loading. Please wait...", true);
            new CallAsynClass().execute();
        }

       private class CallAsynClass extends AsyncTask<URL, Integer, Long> {
          protected Long doInBackground(URL... urls) {
            //do something
          }
          protected void onProgressUpdate(Integer... progress) {
            //do something
          }
          protected void onPostExecute(Long result) {
                progressBar.dismiss();
            //do something
          }
          protected void onPreExecute(){
                progressBar.show();

ProgressLoadingDelayTime();
    //do something
          }
       }
       public void ProgressLoadingDelayTime(){
      Handler handler = new Handler();
      handler.postDelayed(new Runnable() {
           @Override
    public void run() {
                 progressBar.dismiss();
            }
              }, 25000); 

       }
}