How to Call a SOAP Web Service from an Android Application

What is the best way to call a SOAP web service in an Android application?

// Code snippet example will go here.

Calling a SOAP web service from an Android application involves using a client library that simplifies the process of network communication, XML parsing, and SOAP envelope creation. In this guide, we'll explore the most popular options, including kSoap2, which is widely used for SOAP communication in Android.

import org.ksoap2.SoapEnvelope;
import org.ksoap2.serialization.SoapObject;
import org.ksoap2.serialization.SoapSerializationEnvelope;
import org.ksoap2.transport.HttpTransportSE;

// Main method to call a SOAP web service
public void callSoapWebService() {
    String NAMESPACE = "http://yourWebServiceNamespace/";
    String METHOD_NAME = "YourMethodName";
    String SOAP_ACTION = NAMESPACE + METHOD_NAME;
    String URL = "http://your_web_service_url?wsdl";

    SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
    // Add parameters if needed
    request.addProperty("parameter_name", "parameter_value");

    SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
    envelope.dotNet = false;
    envelope.setOutputSoapObject(request);
    HttpTransportSE transport = new HttpTransportSE(URL);

    try {
        transport.call(SOAP_ACTION, envelope);
        SoapObject response = (SoapObject) envelope.getResponse();
        // Handle response here
    } catch (Exception e) {
        e.printStackTrace();
    }
}

Causes

• Lack of familiarity with SOAP and XML protocols.
• Difficulty in finding updated libraries or tutorials.
• The complexity of handling SOAP headers and envelopes manually.

Solutions

• Use kSoap2 for easy SOAP requests and responses handling.
• Utilize Android's built-in HttpURLConnection or a library like Retrofit with a SOAP converter.
• Consider using tools that auto-generate client classes from WSDL files.

Mistake: Not handling network operations on a separate thread, leading to UI thread blocking.

Solution: Use AsyncTask or Kotlin Coroutines to run network calls off the main thread.

Mistake: Ignoring SOAP envelope structure leading to incorrect responses.

Solution: Ensure you correctly define the envelope and its namespace according to the WSDL.