Parsing XML response in your Android App @ Mini App / Calling WebServices

Dear All

In the previous post i had uploaded how to generate XML response from Database.
Now in this post i am going to upload an android code by which you can fetch data into a ListView from any file which is generating XML response .
These kind of files are generally termed as web services.
To see please visit a live resource on

http://services.hanselandpetal.com/feeds/flowers.xml

So how you can parse such kind of response in your Android App. Below mentioned code is little bit tricky don't get confused.
I had create
A. Layout
     a. Layout for MainActivity
     b. Layout for a single row
B. Java Code
     a. ConnManager Class to read the data from given url in a string format
     b. A class to hold information in a manner as generated by XML  - Person
     c.  A Parser class to parse data from generated string in step-a into proper format like List
          PersonXMLParser
     d. An Adapter to provide data to ListView PersonAdapter
     e. MainActivity to work as a Controller
C. Output

So i think you understand the project structure lets see the code
A. Layout code
    a.

<ListView    android:id="@android:id/list"

    android:layout_width="match_parent"

    android:layout_height="wrap_content"

    android:layout_below="@+id/button"

    android:layout_marginTop="10dp">

</ListView>

<ProgressBar

    android:id="@+id/progressBar1"

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:layout_centerHorizontal="true"

    android:layout_centerVertical="true" />

<Button

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:text="Click for Data"

    android:id="@+id/button"

    android:onClick="loadData"

    android:layout_alignParentTop="true"

    android:layout_centerHorizontal="true" />

b. Single Row

<TextView    android:layout_width="wrap_content"

    android:layout_height="40dp"

    android:text="New Text"

    android:id="@+id/name"

    android:gravity="center_vertical"

    android:layout_alignParentTop="true"

    android:layout_alignParentStart="true" />

<TextView

    android:layout_width="wrap_content"

    android:layout_height="40dp"

    android:text="New Text"

    android:id="@+id/address"

    android:gravity="center_vertical"

    android:layout_alignParentTop="true"

    android:layout_centerHorizontal="true" />


B. Java Code 
  a. ConnManager
package com.example.ravigodara.parsejsonxml;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

/** * Created by Ravi Godara on 10/9/2016. */public class ConnManager {
    public static String getData(String uri)
    {
        BufferedReader reader=null;
        try {
            URL url=new URL(uri);
            HttpURLConnection con=(HttpURLConnection) url.openConnection();
            StringBuilder sb=new StringBuilder();
            reader=new BufferedReader(new InputStreamReader(con.getInputStream()));
            String line;
            while ((line=reader.readLine())!=null) {
                sb.append(line+"\n");
            }
            return sb.toString();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        finally{
            if(reader!=null)
            {
                try {
                    reader.close();
                } catch (IOException e) {

                    e.printStackTrace();
                    return null;
                }
            }
        }
    }
}

b. Person Class
package com.example.ravigodara.parsejsonxml;

public class Person
{
    private int my_id;
    private String fname;
    private String address;
    public int getMy_id() {
        return my_id;
    }

    public void setMy_id(int my_id) {
        this.my_id = my_id;
    }

    public String getFname() {
        return fname;
    }

    public void setFname(String fname) {
        this.fname = fname;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

}

c. XML Parser class as 


package com.example.ravigodara.parsejsonxml;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;

import java.io.StringReader;
import java.util.ArrayList;
import java.util.List;

public class PersonXMLParser {
    public static List<Person> parseFeed(String content)
    {
        try        {
            boolean inDataItemTag=false;
            String currentTagName="";
            Person person=null;
            List<Person> personList=new ArrayList<>();
            XmlPullParserFactory factory=XmlPullParserFactory.newInstance();
            XmlPullParser parser=factory.newPullParser();
            parser.setInput(new StringReader(content));
            int eventType=parser.getEventType();
            while(eventType!=XmlPullParser.END_DOCUMENT)
            {
              
                switch(eventType)
                {
                    case XmlPullParser.START_TAG:
                        currentTagName=parser.getName();
                        if(currentTagName.equals("personal"))
                        {
                            inDataItemTag=true;
                            person=new Person();
                            personList.add(person);
                        }
                        break;
                    case XmlPullParser.END_TAG:
                        if(parser.getName().equals("personal"))
                        {
                            inDataItemTag=false;
                        }
                        currentTagName = "";
                        break;

                    case XmlPullParser.TEXT:
                        if(inDataItemTag && (person != null)){

                            switch(currentTagName)
                            {
                                case "uid":
                                  person.setMy_id(Integer.parseInt(parser.getText()));
                                    break;
                                case "first_name":
                                    person.setFname(parser.getText());
                                    break;
                                case "address":
                                    person.setAddress(parser.getText());
                                    break;

                                default:
                                    break;
                            }
                        }
                        break;
                }
                eventType=parser.next();
            }
            return personList;
        }catch(Exception e)
        {
            e.printStackTrace();
            return null;
        }
    }

}

d. Adapter as 
package com.example.ravigodara.parsejsonxml;

import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

import java.util.List;


public class PersonAdapter extends ArrayAdapter<Person> {
    private Context context;
    private List<Person> personList;


    public PersonAdapter(Context context, int resource, List<Person> objects)
     {
        super(context, resource, objects);
        this.context = context;
        this.personList = objects;
    }

    @Override

    public View getView(int position, View convertView, ViewGroup parent) {
        LayoutInflater inflater = (LayoutInflater)
                  context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        View view = inflater.inflate(R.layout.single_person, parent, false);
        Person person = personList.get(position);
        TextView textView1 = (TextView) view.findViewById(R.id.name);
        TextView textView2 = (TextView) view.findViewById(R.id.address);
        textView1.setText(person.getFname());
        textView2.setText(person.getAddress());

        return view;

    }
}

e. MainActivity as 

package com.example.ravigodara.parsejsonxml;

import android.app.ListActivity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.method.ScrollingMovementMethod;
import android.view.View;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends ListActivity {
    ProgressBar pb;
    List<MyTask> tasks;
    List<Person> personList;

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        pb=(ProgressBar) findViewById(R.id.progressBar1);
        pb.setVisibility(View.INVISIBLE);
        tasks=new ArrayList<>();
    }
    public void loadData(View view)
    {
        requestData("http://10.0.2.2/anddb/xmlres.php");
    }
    private void requestData(String uri) {
        MyTask task=new MyTask();
        task.execute(uri);
    }
   
    private class MyTask extends AsyncTask<String, String, String> {

        @Override        protected void onPreExecute() {
            
            if(tasks.size()==0)
            {
                pb.setVisibility(View.VISIBLE);
            }
            tasks.add(this);
        }
        @Override        protected String doInBackground(String... params) {
            String content=ConnManager.getData(params[0]);
            return content;
        }
        @Override        protected void onPostExecute(String result) {
          
            personList=PersonXMLParser.parseFeed(result);
            updateDisplay();
            tasks.remove(this);
            if(tasks.size()==0)
            {
                pb.setVisibility(View.INVISIBLE);
            }

        }
        @Override        protected void onProgressUpdate(String... values) {
            //updateDisplay(values[0]);        }
    }
    protected void updateDisplay() {
      
        PersonAdapter adapter = new PersonAdapter(this,
                              R.layout.single_person, personList);
        setListAdapter(adapter);
    }
}

C. output as 






**** Don't forget t add Internet Permission in manifest file