我需要调用到一个SAP网络服务使用Android获取材料没有使用材料文件没有。我正在使用ksoap 2库。问题是我不知道NAMESPACE，SOAP_ACTION到底是什么意思。我得不到任何回应。

方法名称=“ZSL_GET_MAT_DOC”;
URL =“http://SL_S：*@AP.vv.lk：8000/sap/bc/srt/rfc/sap/zsl_get_mat_doc/110/zsl_get_mat_doc/zl_web_svr4”;

这是我的方法。

class RetrieveFeedTask extends AsyncTask<String, Void, String> {
        @Override
        protected String doInBackground(String... strings) {

            // Create SOAP request
            SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
            request.addProperty("Materialdocument", "0407000147");

            SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
            envelope.setOutputSoapObject(request);
            HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
            try {
                androidHttpTransport.call(SOAP_ACTION, envelope);

                // Get response from envelope
                Object result = envelope.getResponse();

                // Display result
                Toast.makeText(getContext(), result.toString(), Toast.LENGTH_LONG).show();

            } catch (IOException e) {
                e.printStackTrace();
            } catch (XmlPullParserException e) {
                e.printStackTrace();
            }

            return null;
        }
    }

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