onContenLoaded没有输出，那就是他没有被调用。你去看看是那个位置需要调用。什么时候调用的。你就知道bug在哪里了。

onContentLoaded没Log输出，那证明什么呢？证明你这个方法没运行。那没运行的话你是不是得再往上追踪一下？其实数据没加载出来很简单，你请求到数据之后做了什么才是关键的

这种问题跟着数据流走就好。

数据请求回来，确定有回来没有---->设置到适配器里----> 绑定数据---->确保有设置布局管理器，item你可以设置一个背景，硬编码一个高度，这样就知道哪个环节有问题了。

debug了一下 callbacks的值是0 这是什么问题啊

public class CategoryPagerPresenterImpl implements ICategoryPagerPresenter {
    private Map<Integer,Integer> pageInfo = new HashMap<>();

    public static final int DEFAULT_PAGE = 1;

    private CategoryPagerPresenterImpl(){

    }
    private static ICategoryPagerPresenter sInstance = null;
    public static ICategoryPagerPresenter getInstance(){
        if (sInstance == null) {
            sInstance = new CategoryPagerPresenterImpl();
        }
        return sInstance;
    }


    @Override
    public void getContentByCategoryId(int categoryId) {
        //加载内容根据分类id
        for (ICategoryPagerCallback callback : callbacks) {
            if (callback.getCategoryId()==categoryId){
                callback.onLoading();
            }
        }
        Retrofit retrofit = RetrofitManager.getInstance().getRetrofit();
        API api = retrofit.create(API.class);
        Integer targetPage = pageInfo.get(categoryId);
        if (targetPage==null) {
            targetPage = DEFAULT_PAGE;
            pageInfo.put(categoryId,targetPage);
        }
        String homePagerUrl = UrlUtils.createHomePagerUrl(categoryId,targetPage );
        LogUtils.d(this,"home page url"+homePagerUrl);
        Call<HomePagerContent> task = api.getHomePagerContent(homePagerUrl);
        task.enqueue(new Callback<HomePagerContent>() {
            @Override
            public void onResponse(Call<HomePagerContent> call, Response<HomePagerContent> response) {
                int code = response.code();
                LogUtils.d(CategoryPagerPresenterImpl.this,"code-->"+code);
                if (code == HttpURLConnection.HTTP_OK) {
                    HomePagerContent pagerContent = response.body();
                    LogUtils.d(CategoryPagerPresenterImpl.this,"pagecontent"+pagerContent);
                    //把数据给到ui
                    handleHomePageContentResult(pagerContent,categoryId);

                }else {
                        handleNetworkError(categoryId);
                }
            }

            @Override
            public void onFailure(Call<HomePagerContent> call, Throwable t) {
                LogUtils.d(CategoryPagerPresenterImpl.this,"onFailure-->"+t.toString());
                handleNetworkError(categoryId);

            }
        });
    }

    private void handleNetworkError(int categoryId) {
        for (ICategoryPagerCallback callback : callbacks) {
            if (callback.getCategoryId()==categoryId) {
                callback.onNetworkError();
            }
        }

    }

    private void handleHomePageContentResult(HomePagerContent pagerContent, int categoryId) {
        //通知UI层更新数据

        List<HomePagerContent.DataBean> data = pagerContent.getData();
        for(ICategoryPagerCallback callback:callbacks){
            if (callback.getCategoryId()==categoryId) {
                if (pagerContent==null|| data.size()==0) {
                callback.onEmpty();
            }else{

                    List<HomePagerContent.DataBean> looperData = data.subList(data.size() - 5, data.size());
                    callback.onLooperListLoaded(looperData);
                    callback.onContentLoaded(data);
                }
            }
        }
    }

    @Override
    public void loadMore(int categoryId) {

    }

    @Override
    public void reLoad(int categoryId) {

    }
    private List<ICategoryPagerCallback> callbacks = new ArrayList<>();

    @Override
    public void registerViewCallback(ICategoryPagerCallback callback) {

        if (callbacks.contains(callback)) {
            callbacks.add(callback);
        }

    }

    @Override
    public void unregisterViewCallback(ICategoryPagerCallback callback) {
        callbacks.remove(callback);
    }
}