HttpRequest* request = new HttpRequest();
request->setUrl("http://just-make-this-request-failed.com");
request->setRequestType(HttpRequest::Type::GET);
request->setResponseCallback(this, httpresponse_selector(HttpClientTest::onHttpRequestCompleted));
这段代码来自 cocos2d-x 3.0 的 NetworkTest。我不明白为什么我应该将 Layer* 传递给 setResponseCallback?如果我想在不创建单层的情况下发送/获取请求/响应怎么办?为什么我不能这样做?