TestGeneralize.java

private void openImage(long imageId) {
        if (disposable != null) {
            disposable.dispose();
        }
        disposable = commonService.getImageById(imageId)
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .onErrorResumeNext(error -> Single.error(ApiExceptionUtil.generalException(error)))
                .subscribe(v -> {
                    hideProgress();
                    context().ifPresent(c -> FullscreenImageViewerActivity.Companion.show(c, v.images()));
                }, error -> {
                    hideProgress();
                    handleError(error);
                });
}

private void openVideo(long videoId) {
        if (disposable != null) {
            disposable.dispose();
        }
        disposable = commonService.getVideoById(videoId)
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .onErrorResumeNext(error -> Single.error(ApiExceptionUtil.generalException(error)))
                .subscribe(v -> {
                    hideProgress();
                    context().ifPresent(c -> YoutubePlayerActivity.show(c, v));
                }, error -> {
                    hideProgress();
                    handleError(error);
                });
}

private void openCategory(long id){
        if (disposable != null) {
            disposable.dispose();
        }
        disposable = commonService.getCategoryById(id)
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                 .onErrorResumeNext(error -> Single.error(ApiExceptionUtil.generalException(error)))
                .subscribe(cat -> {
                    hideProgress();
                    context().ifPresent(c -> DetailActivity.show(c, cat));
                }, error -> {
                    hideProgress();
                    activity().ifPresent(a -> DialogUtil.showOk(a, error.getLocalizedMessage()));
                });
}