使用 AsyncTask 并将值返回给 UI 主线程
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【中文标题】使用 AsyncTask 并将值返回给 UI 主线程【英文标题】:Using AsyncTask and returning values to the UI main thread 【发布时间】:2012-08-23 04:47:08 【问题描述】: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;
我想要做的是将 String 结果值返回到主 UI,以便我可以将该值设置到 textview。
String result;
TextView tv=findViewById(R.id.textView1);
tv.setText(result);
我该怎么做?
【问题讨论】:
【参考方案1】:你应该Override
onPostExecute()
方法。
类似这样的:
@Override
protected void onPostExecute(String result)
TextView tv = findViewById(R.id.textView1);
tv.setText(result);
【讨论】:
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