Java 使用AsyncTask并将值返回到UI主线程

Java 使用AsyncTask并将值返回到UI主线程,java,android-asynctask,Java,Android Asynctask,我有一个Android活动来显示web服务的输出。我在另一个扩展AsyncTask的私有类中调用了web服务,并希望向主UI线程返回一个值 这是我的活动 public class CallCalcService extends Activity { private String METHOD_NAME = "sum"; // our webservice method name private String NAMESPACE = "http://backend.android.web.org

我有一个Android活动来显示web服务的输出。我在另一个扩展AsyncTask的私有类中调用了web服务,并希望向主UI线程返回一个值

这是我的活动

public class CallCalcService extends Activity {

private String METHOD_NAME = "sum"; // our webservice method name
private String NAMESPACE = "http://backend.android.web.org"; 

private String SOAP_ACTION = NAMESPACE + METHOD_NAME; 

private static final String URL = "http://192.168.1.14:8080/AndroidBackend1/services/Calculate?wsdl"; 

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_call_calc_service);

    //TextView tv = (TextView) findViewById(R.id.textView1);
    //Object res=new HardWorkThread().execute();
    //tv.setText("Addition : "+ res.toString());

    new HardWorkThread()
    {
        public void onPostExecute(String result)
        {
            TextView txt = (TextView) findViewById(R.id.textView1);
            txt.setText("Addition : "+result);
        }
    }.execute("");



}

private class HardWorkThread extends AsyncTask{

    @Override
    protected String doInBackground(Object... params) {
        // TODO Auto-generated method stub
        String result=null;
        try {
            SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
            request.addProperty("i", 5);
            request.addProperty("j", 15);
            SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
                    SoapEnvelope.VER11);
            envelope.dotNet = true;
            envelope.setOutputSoapObject(request);
            HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
            androidHttpTransport.call(SOAP_ACTION,envelope);

             result = envelope.getResponse().toString();
            System.out.println("Result : " + result);
            //((TextView) findViewById(R.id.textView1)).setText("Addition : "+ result.toString());
        } catch (Exception E) {
            E.printStackTrace();
            //((TextView) findViewById(R.id.textView1)).setText("ERROR:"
                //  + E.getClass().getName() + ":" + E.getMessage());
        }
        return result;
    }



}
}

我要做的是将字符串结果值返回到主UI,以便将该值设置到textview

String result;

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

我该怎么做?

您应该
重写
onPostExecute()
方法

大概是这样的:

        @Override
    protected void onPostExecute(String result) {
        TextView tv = findViewById(R.id.textView1);
        tv.setText(result);
    }