可能重复:
NetworkOnMainThreadException
长期以来,我一直在使用在AsyncTask中执行http请求的通用代码。AsyncTask返回一个HttpResponse对象。一切都很好,gui线程从未冻结。
现在,突然之间,这就产生了一个NetworkOnMainThreadException

serverResponse.getEntity().getContent();

搞什么鬼??为什么要考虑联网??在我看来,这一行只是将响应转换为inputstream,不需要网络连接。谁做了这个决定?为什么他们认为这应该是网络?
异步任务:
public class AsyncHttpTask extends AsyncTask<HttpRequestInfo, Integer, HttpRequestInfo> {

public AsyncHttpTask() {
    super();
}

protected HttpRequestInfo doInBackground(HttpRequestInfo... params) {
    HttpRequestInfo rinfo = params[0];
    try{
        HttpClient client = new DefaultHttpClient();
        HttpResponse resp = client.execute(rinfo.getRequest());
        rinfo.setResponse(resp);
    }
    catch (Exception e) {
        rinfo.setException(e);
    }
    return rinfo;
}

@Override
protected void onPostExecute(HttpRequestInfo rinfo) {
    super.onPostExecute(rinfo);
    rinfo.requestFinished();
}

回调接口:
    public interface HttpCallback {

        public void onResponse(HttpResponse serverResponse);
        public void onError(Exception e);

    }

httprequestinfo:
public class HttpRequestInfo {

    private HttpUriRequest request_;
    private HttpCallback callback_;
    private Exception exception_;
    private HttpResponse response_;

    public HttpRequestInfo(HttpUriRequest request, HttpCallback callback) {
        super();
        request_ = request;
        callback_ = callback;
    }

    public HttpUriRequest getRequest() {
        return request_;
    }

    public void setRequest(HttpUriRequest request) {
        request_ = request;
    }

    public HttpCallback getCallback() {
        return callback_;
    }

    public void setCallback(HttpCallback callback) {
        callback_ = callback;
    }

    public Exception getException() {
        return exception_;
    }

    public void setException(Exception exception) {
        exception_ = exception;
    }

    public HttpResponse getResponse() {
        return response_;
    }

    public void setResponse(HttpResponse response) {
        response_ = response;
    }

    public void requestFinished(){
        if(exception_ != null){
            callback_.onError(exception_);
        }
        else {
            callback_.onResponse(response_);
        }
    }
}

然后我使用jackson将json响应转换为一个对象。这就是发生异常的地方:
@Override
public <T> T handleResponse(HttpResponse serverResponse, Class<T> typeOfResponse) {
    ObjectMapper mapper = new ObjectMapper();
    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
    T responseObject = null;
    try {
        responseObject = mapper.readValue(serverResponse.getEntity().getContent(),typeOfResponse); //THIS LINE IS EVIL
    } catch (JsonParseException e) {
        throw new ARException("Couldn't handle the response because the http response contained malformed json.",e);
    } catch (JsonMappingException e) {
        throw new ARException("Mapping the json response to the response object " + typeOfResponse + " failed.",e);
    } catch (IllegalStateException e) {
        throw new ARException("Couldn't convert the http response to an inputstream because of illegal state.",e);
    } catch (IOException e) {
        throw new ARException("Couldn't convert the http response to an inputstream.",e);
    }
    return responseObject;
}

最佳答案

因为您必须在单独的线程而不是主线程中使用网络。您可以使用AsyncTaskThread+Handler。如果使用的是asynctask all work with network,则必须在doinbackground部分执行。

07-28 02:14
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