Android Web Service Access Tutorial

In this post I'm going to illustrate how we can access web service in Android using ksoap2-android project that provides a lightweight and efficient SOAP library for the Android platform.

You can download the jar file from following link;

http://ksoap2-android.googlecode.com/svn/m2-repo/com/google/code/ksoap2-android/ksoap2-android-assembly/2.5.8/ksoap2-android-assembly-2.5.8-jar-with-dependencies.jar

Here is the sample code that illustrate SOAP web service call. I have access a live web service ConvertWeight from http://www.webserviceX.NET/ which convert weight from one unit to another. I have set "envelope.dotNet = true;" in Line 53 since I'm accessing .NET web service. You can comment that line if your web service is not .NET one.

package com.sencide;
 
import org.ksoap2.SoapEnvelope;
import org.ksoap2.serialization.PropertyInfo;
import org.ksoap2.serialization.SoapObject;
import org.ksoap2.serialization.SoapPrimitive;
import org.ksoap2.serialization.SoapSerializationEnvelope;
import org.ksoap2.transport.HttpTransportSE;
 
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
 
public class AndroidWebService extends Activity {
  
    private final String NAMESPACE = "http://www.webserviceX.NET/";
    private final String URL = "http://www.webservicex.net/ConvertWeight.asmx";
    private final String SOAP_ACTION = "http://www.webserviceX.NET/ConvertWeight";
    private final String METHOD_NAME = "ConvertWeight";
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
 
        SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME); 
      
        String weight = "3700";
        String fromUnit = "Grams";
        String toUnit = "Kilograms";
      
        PropertyInfo weightProp =new PropertyInfo();
        weightProp.setName("Weight");
        weightProp.setValue(weight);
        weightProp.setType(double.class);
        request.addProperty(weightProp);
         
        PropertyInfo fromProp =new PropertyInfo();
        fromProp.setName("FromUnit");
        fromProp.setValue(fromUnit);
        fromProp.setType(String.class);
        request.addProperty(fromProp);
         
        PropertyInfo toProp =new PropertyInfo();
        toProp.setName("ToUnit");
        toProp.setValue(toUnit);
        toProp.setType(String.class);
        request.addProperty(toProp);
        
        SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
        envelope.dotNet = true;
        envelope.setOutputSoapObject(request);
        HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
 
        try {
            androidHttpTransport.call(SOAP_ACTION, envelope);
            SoapPrimitive response = (SoapPrimitive)envelope.getResponse();
            Log.i("myApp", response.toString());
    
            TextView tv = new TextView(this);
            tv.setText(weight+" "+fromUnit+" equal "+response.toString()+ " "+toUnit);
            setContentView(tv);
 
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

You have to add INTERNET permission to AndroidManifest.xml as follows;

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.sencide"
      android:versionCode="1"
      android:versionName="1.0">

    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".AndroidWebService"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
    
    <uses-permission android:name="android.permission.INTERNET"></uses-permission>
</manifest>

You can download the source code of above project (Password:sara).

I have updated my previous code in the post Android Login Screen Using HttpClient to authenticate users from web service. There I have illustrated how you can start new activity if the login is successful.

You can download the updated source code with sample .NET web service application (Password:sara).