Question

I am running a simple project where on clicking a button in android. A message is displayed returned from a webservice whose coding is done in java.

Here is my program in eclipse for Android:

@Override
public void onClick(View v) {
    final String url = "http://10.0.2.2:8050/WebPractice/PracticeWebServices?wsdl";
    final String namespace = "http://PracticeWebServices/";
    final String methodName = "hello";
    final String action = namespace + methodName;

    if(v.getId() == submit_btn.getId()) {
        SoapObject so = new SoapObject(namespace, methodName);
        so.addProperty("name", "Arjun");
        SoapSerializationEnvelope sse = new SoapSerializationEnvelope(SoapEnvelope.VER11);
        sse.setOutputSoapObject(so);
        HttpTransportSE hse = new HttpTransportSE(url);

        try {
            hse.call(action, sse);
            SoapPrimitive primitive = (SoapPrimitive)sse.getResponse();
            Toast.makeText(getApplicationContext(),primitive.toString() , Toast.LENGTH_SHORT);
        } catch(IOException e) {
            e.printStackTrace();
        } catch (XmlPullParserException e) {
            e.printStackTrace();
        }
    }
}

Following is my code in Java:

@WebService(serviceName = "PracticeWebServices")
public class PracticeWebServices {

    @WebMethod(operationName = "hello")
    public String hello(@WebParam(name = "name") String name) {
        return "Hello " + name + " !";
    }
}

I’ve included the internet permission in manifest file….

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

Now, when I’m running the file in the emulator provided in Eclipse. On clicking the button it shows me a message Unfortunately the program has stopped

When i checked the logCat….Seems like i m hitting an exception at android.os.NetworkOnMainThreadException

Answer 1

You should put your long networking fetching operation in either a Thread or AsyncTask

I suggest you to use AsyncTask

you can do something like this by creating a class that extends AsyncTask

private class LongNetworkOperation extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... params) {

        SoapObject so = new SoapObject(namespace, methodName);
        so.addProperty("name", "Arjun");
        SoapSerializationEnvelope sse = new SoapSerializationEnvelope(SoapEnvelope.VER11);
        sse.setOutputSoapObject(so);
        HttpTransportSE hse = new HttpTransportSE(url);

        try {
            hse.call(action, sse);
            SoapPrimitive primitive = (SoapPrimitive)sse.getResponse();
            Toast.makeText(getApplicationContext(),primitive.toString() , Toast.LENGTH_SHORT);
        } catch(IOException e) {
            e.printStackTrace();
        } catch (XmlPullParserException e) {
            e.printStackTrace();
        }
    }
}

and you can call it on your onClick() like this

@Override
public void onClick(View v) {
    if(v.getId()==submit_btn.getId()) {
        new LongNetworkOperation.execute();
    }
}

Also I suggest you to show a ProgressDialog on onPreExecute() and hide it in onPostExecute() so that the user will be aware of the long background process which is highly recommended for long operations