android - 无法将 Android 连接到 Web 服务

Question

您好，我正在试验 android 到 web 服务的连接。为了做到这一点，我完成的步骤是:

1. 查找免费网络服务:http://services.aonaware.com/DictService/DictService.asmx

2. 在 Android Studio 上创建一个基本 Activity

3. 通过添加以下行更改 Manifest 文件以允许使用互联网:

   使用权限 android:name="android.permission.INTERNET"

4. 添加ksoap2库

5. 尝试使用以下代码使用网络服务:

declarations

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    tv = (TextView) findViewById(R.id.textView1);

    SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
    PropertyInfo property = new PropertyInfo();
    property.setName("word");
    //property.setType(String.class);
    property.setValue("computer");
    request.addProperty(property);


    SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
    envelope.setOutputSoapObject(request);

    HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
    Object response = null;
    try {
        androidHttpTransport.getServiceConnection();

        try {
            androidHttpTransport.call(SOAP_ACTION, envelope);
        } catch (IOException e) {
            e.printStackTrace();
        } catch (XmlPullParserException e) {
            e.printStackTrace();
        }
        tv.setText("success");
        response =  envelope.getResponse();
        response.toString();
        String resultData= response.toString();
        tv.setText(resultData);

    } catch (Exception e) {
       e.printStackTrace();
    }
}

但是，textView1 没有得到结果。我的代码有什么问题吗？

注意:我使用带有 Gradle 版本 2.10 的 Android Studio

Answer 1

尝试使用 AsyncTask 来执行 Web 服务。这是一个示例 -> android.os.NetworkOnMainThreadException for webservice (ksoap)

import org.ksoap2.SoapEnvelope;
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.AsyncTask;
import android.os.Bundle;
import android.util.Log;

public class MainActivity extends Activity {
    private String TAG ="Vik";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        AsyncCallWS task = new AsyncCallWS();
        task.execute(); 
    }

    private class AsyncCallWS extends AsyncTask<Void, Void, Void> {
        @Override
        protected Void doInBackground(Void... params) {
            Log.i(TAG, "doInBackground");
            calculate();
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            Log.i(TAG, "onPostExecute");
        }

        @Override
        protected void onPreExecute() {
            Log.i(TAG, "onPreExecute");
        }

        @Override
        protected void onProgressUpdate(Void... values) {
            Log.i(TAG, "onProgressUpdate");
        }

    }

    public void calculate() 
    {
        String SOAP_ACTION = "http://tempuri.org/CelsiusToFahrenheit";
        String METHOD_NAME = "CelsiusToFahrenheit";
        String NAMESPACE = "http://tempuri.org/";
        String URL = "http://www.w3schools.com/webservices/tempconvert.asmx";

        try { 
            SoapObject Request = new SoapObject(NAMESPACE, METHOD_NAME);
            Request.addProperty("Celsius", "32");

            SoapSerializationEnvelope soapEnvelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
            soapEnvelope.dotNet = true;
            soapEnvelope.setOutputSoapObject(Request);

            HttpTransportSE transport= new HttpTransportSE(URL);

            transport.call(SOAP_ACTION, soapEnvelope);
            SoapPrimitive resultString = (SoapPrimitive)soapEnvelope.getResponse();

            Log.i(TAG, "Result Celsius: " + resultString);
        }
        catch(Exception ex) {
            Log.e(TAG, "Error: " + ex.getMessage());
        }

        SOAP_ACTION = "http://tempuri.org/FahrenheitToCelsius";
        METHOD_NAME = "FahrenheitToCelsius";
        try { 
            SoapObject Request = new SoapObject(NAMESPACE, METHOD_NAME);
            Request.addProperty("Fahrenheit", "100");

            SoapSerializationEnvelope soapEnvelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
            soapEnvelope.dotNet = true;
            soapEnvelope.setOutputSoapObject(Request);

            HttpTransportSE transport= new HttpTransportSE(URL);

            transport.call(SOAP_ACTION, soapEnvelope);
            SoapPrimitive resultString = (SoapPrimitive)soapEnvelope.getResponse();

            Log.i(TAG, "Result Fahrenheit: " + resultString);
        }
        catch(Exception ex) {
            Log.e(TAG, "Error: " + ex.getMessage());
        }
    }

}