求助 cocos2d-x 如何设置Object C的代理

UIImagePickerController *imagePickerController =  init];

imagePickerController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
imagePickerController.delegate = ctrol;
imagePickerController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;

;
;

比如我要用 UIImagePickerController, 这个 delegate 如何设置才对.
在HelloWorldScene.mm(HelloWorldScene.cpp) 里面.

我是自己写了一个代理类,然后用混编做个桥接调用