java-在Android中异步更新UI

我有一个每10秒调用一次的Web服务调用,并且应该使用Web服务回复来更新TextView(或每10秒至少显示一条祝酒消息)

但是,UI根本没有更新.

请在下面找到代码.

public class MessagesRequestActivity extends Activity  {
    /** Called when the activity is first created. */
    String currentMsg="Default";
    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        //Calling the webservice
        getMessage();
    }
    public void getMessage(){

        try
        {
        SoapObject request = new SoapObject("http://tempuri.org/", "getMessage");

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

        //Web method call
        HttpTransportSE androidHttpTransport = new HttpTransportSE("http://192.168.4.50/WebService.asmx");
        androidHttpTransport.call("http://tempuri.org/"+ "getMessage", envelope);
        //get the response
        SoapPrimitive response = (SoapPrimitive)envelope.getResponse();

        //the response object can be retrieved by its name: result.getProperty("objectName");
        String message = (String)response.toString();
        Toast.makeText(this, message, Toast.LENGTH_LONG).show();

        }
        catch (Exception e)
        {
        e.printStackTrace();
        }
        try {
            Thread.sleep(10000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        }
}

解决方法:

这是一个AsyncTask的例子

public class TalkToServer extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
    super.onPreExecute();
}

@Override
protected void onProgressUpdate(String... values) {
    super.onProgressUpdate(values);

}

@Override
protected String doInBackground(String... params) {
//do your work here
    return something;
}

@Override
protected void onPostExecute(String result) {
    super.onPostExecute(result);
       // do something with data here-display it or send to mainactivity
}

然后,您可以通过调用

TalksToServer varName = new TalkToServer(); //pass parameters if you need to the constructor
varName.execute();

Async Docs
Progress Dialog Example

您不想做网络工作或不想在UI线程上调用sleep.如果它是内部类,那么您将可以访问外部类的成员变量.否则,如果要从onPostExecute或其他方法dosBacks doInBackground()更新,请在AsyncTask类中创建构造函数以传递上下文.

标签：android-sdk-2-3,android,java
来源： https://codeday.me/bug/20191013/1906279.html