Progress Bar Tutorial in Android

Progress Bar Tutorial in Android Application :

Download the whole project!

In this tutorial I am using my previous project (you can see the post here) in which I fetched the data from my blog using JSOUP library. In this project, I made a progress dialog till the network operation occur.

In progress dialog there is a dialog with the message and a spinner which revolves till the network operation or any background task.

During the data is fetched in the background, progress dialog is used to give the user a better interaction in the android application.

Create new project in Eclipse : File => New => Android Application Project and give any package name.

Code for activity_main.xml is same as previous tutorial and is shown below :

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
   xmlns:tools="http://schemas.android.com/tools"  
   android:layout_width="match_parent"  
   android:layout_height="match_parent"  
   android:orientation="vertical"  
   >  
   
   <LinearLayout   
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:orientation="horizontal"  
     >  
   <TextView  
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:text="TITLE :"   
     android:textSize="20sp"  
     android:textStyle="bold"  
     android:layout_marginLeft="15px"  
     android:layout_marginTop="10px"  
       
     />  
   <TextView  
     android:id="@+id/titleText"  
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:textSize="18sp"  
     android:layout_marginLeft="15px"  
     android:layout_marginTop="10px"  
     />  
   
   </LinearLayout>  
     
     
   <TextView  
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:text="POSTS TITLE :"   
     android:textSize="20sp"  
     android:textStyle="bold"  
     android:layout_marginLeft="15px"  
     android:layout_marginTop="10px"  
       
     />  
   <TextView  
     android:id="@+id/postsText"  
     android:layout_width="wrap_content"  
     android:layout_height="wrap_content"  
     android:textSize="15sp"  
     android:layout_marginLeft="15px"  
     android:layout_marginTop="10px"  
     />   
 </LinearLayout>  
   

This code is used to show the posts title and blog title in text views. You can refer my previous tutorial.

Now code for MainActivity.java is shown below :

 package com.javalanguageprogramming.jsoupdemo;  
   
 import org.jsoup.Jsoup;  
 import org.jsoup.nodes.Document;  
 import org.jsoup.select.Elements;  
   
 import android.app.Activity;  
 import android.app.ProgressDialog;  
 import android.os.Bundle;  
 import android.widget.TextView;  
   
   
 public class MainActivity extends Activity {  
   
      TextView titleText, postText;  
      String title, posts = "";  
      ProgressDialog progressDialog;  
        
      @Override  
      protected void onCreate(Bundle savedInstanceState) {  
           super.onCreate(savedInstanceState);  
           setContentView(R.layout.activity_main);  
             
           //initialize variables  
           titleText = (TextView)findViewById(R.id.titleText);  
           postText = (TextView)findViewById(R.id.postsText);  
             
           //start progress dialog at the start of network operation  
           progressBarInitialize();  
             
           //run on new thread because we cannot do network operation on main thread  
           new Thread(new Runnable() {  
                  
                @Override  
                public void run() {  
                     try{  
                                 
                     //get the Document object from the site. Enter the link of site you want to fetch  
                     Document document = Jsoup.connect("http://javalanguageprogramming.blogspot.in/").get();  
                       
                     //Get the title of blog using title tag  
                     title = document.select("h1.title").text().toString();  
                     //set the title of text view  
                       
                       
                     //Get all the elements with h3 tag and has attribute a[href]  
                     Elements elements = document.select("div.post-outer").select("h3").select("a[href]");  
                     int length = elements.size();  
                       
                     for(int i=0; i<length; i++){  
                          //store each post heading in the string  
                          posts += elements.get(i).text() + "\n\n";  
                            
                     }  
                       
                     //Run this on ui thread because another thread cannot touch the views of main thread  
                     runOnUiThread(new Runnable() {  
                            
                          @Override  
                          public void run() {  
                                 
                               //set both the text views  
                               titleText.setText(title);  
                               postText.setText(posts);  
                                 
                               //first check if the progress Dialog is already showing than dismiss it  
                               if(progressDialog.isShowing())  
                                    progressDialog.dismiss();  
                          }  
                     });  
                       
                       
                       
                }catch(Exception e){  
                     e.printStackTrace();  
                     //if any exception occurs than progress Dialog should be removed  
                     if(progressDialog.isShowing())  
                          progressDialog.dismiss();  
                }  
                }  
           }).start();  
             
             
 }  
        
      private void progressBarInitialize(){  
           //initialize the progress dialog during the start of network operation  
                     progressDialog = ProgressDialog.show(MainActivity.this, "Loading...", "Fetching the data");  
                     //set the progress dialog to indeterminate state  
                     progressDialog.setIndeterminate(true);  
                     //make the progress dialog not cancellable so that user cannot cancel the network operation  
                     //or you can set it cancellable but for that you need to set the cancel mechanism for the network operation  
                     progressDialog.setCancelable(false);  
                       
      }  
 }  
   

In above activity I used show function of ProgressDialog object and through parameters the message and sub message is passed to show it on the Activity. I initialize the progress dialog when the network operation is started and cancel it when network operation finished.

Do not forget to give the uses permission : Internet for the network operation in this application.