메인 스레드의 Okhttp 응답 콜백

메인 스레드의 Okhttp 응답 콜백

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내 앱에서 모든 http 호출을 처리하기 위해 도우미 클래스를 만들었습니다. 다음과 같은 okhttp 용 단일 래퍼입니다 (중요하지 않은 부분은 생략했습니다).

public class HttpUtil {

    private OkHttpClient client;
    private Request.Builder builder;

    ...

    public void get(String url, HttpCallback cb) {
        call("GET", url, cb);
    }

    public void post(String url, HttpCallback cb) {
        call("POST", url, cb);
    }

    private void call(String method, String url, final HttpCallback cb) {
        Request request = builder.url(url).method(method, method.equals("GET") ? null : new RequestBody() {
            // don't care much about request body
            @Override
            public MediaType contentType() {
                return null;
            }

            @Override
            public void writeTo(BufferedSink sink) throws IOException {

            }
        }).build();

        client.newCall(request).enqueue(new Callback() {
            @Override
            public void onFailure(Request request, Throwable throwable) {
                cb.onFailure(null, throwable);
            }

            @Override
            public void onResponse(Response response) throws IOException {
                if (!response.isSuccessful()) {
                    cb.onFailure(response, null);
                    return;
                }
                cb.onSuccess(response);
            }
        });
    }


    public interface HttpCallback  {

        /**
         * called when the server response was not 2xx or when an exception was thrown in the process
         * @param response - in case of server error (4xx, 5xx) this contains the server response
         *                 in case of IO exception this is null
         * @param throwable - contains the exception. in case of server error (4xx, 5xx) this is null
         */
        public void onFailure(Response response, Throwable throwable);

        /**
         * contains the server response
         * @param response
         */
        public void onSuccess(Response response);
    }

}

그런 다음 주요 활동에서 다음 도우미 클래스를 사용합니다.

HttpUtil.get(url, new HttpUtil.HttpCallback() {
            @Override
            public void onFailure(Response response, Throwable throwable) {
                // handle failure
            }

            @Override
            public void onSuccess(Response response) {
                // <-------- Do some view manipulation here
            }
        });

onSuccess 코드가 실행될 때 예외가 발생합니다.

android.view.ViewRootImpl $ CalledFromWrongThreadException : 뷰 계층 구조를 생성 한 원래 스레드 만 뷰를 터치 할 수 있습니다.

내 이해에서 Okhttp 콜백은 주 스레드에서 실행되므로 왜이 오류가 발생합니까?

** 그냥 보조 노트로, 내가 만든 HttpCallbackOkhttp의 포장 인터페이스를 Callback내가의 동작을 변경을 원하기 때문에 수업을 onResponse하고 onFailure그래서 나는 예외 오 인해 난에 실패 응답 / 인한 서버 문제로 실패 응답을 처리하는 로직을 결합 할 수있다.

감사.

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From my understanding, Okhttp callbacks run on the main thread so why do I get this error ?

This is not true. Callbacks run on a background thread. If you want to immediately process something in the UI you will need to post to the main thread.

Since you already have a wrapper around the callback you can do this internally in your helper so that all HttpCallback methods are invoked on the main thread for convenience.

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As Jake Wharton suggested, I had to run the callbacks on the main thread explicitly.

So I wrapped the calls to the callbacks with Runnable like this:

private void call(String method, String url, final HttpCallback cb) {
    ...

    client.newCall(request).enqueue(new Callback() {
            Handler mainHandler = new Handler(context.getMainLooper());

            @Override
            public void onFailure(Request request,final Throwable throwable) {
                mainHandler.post(new Runnable() {

                    @Override
                    public void run() {
                        cb.onFailure(null, throwable);
                    }
                });

            }

            @Override
            public void onResponse(final Response response) throws IOException {
                mainHandler.post(new Runnable() {

                    @Override
                    public void run() {
                        if (!response.isSuccessful()) {
                            cb.onFailure(response, null);
                            return;
                        }
                        cb.onSuccess(response);
                    }
                });

            }
        });
 }

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I know it's an old question, but recently I encountered the same issue. If you need to update any view, you will need to use runOnUiThread() or post the result back on the main thread.

HttpUtil.get(url, new Callback() { //okhttp3.Callback
   @Override
   public void onFailure(Call call, IOException e) { /* Handle error **/ }

   @Override
   public void onResponse(Call call, Response response) throws IOException {

      String myResponse =  response.body().string();
      //Do something with response
      //...

      MyActivity.this.runOnUiThread(new Runnable() {
            @Override
            public void run() {
               //Handle UI here                        
               findViewById(R.id.loading).setVisibility(View.GONE);                
            }
        });
   }
});

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According to Retrofit documentation Callback methods are executed on UI thread by default until you provide a callback executor to Retrofit OR when using custom method return types using CallAdapterFactory

참고URL : https://stackoverflow.com/questions/24246783/okhttp-response-callbacks-on-the-main-thread