Swift2.0中解决访问资源库函数 - (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error conte错误。

//访问保存照片
UIImageWriteToSavedPhotosAlbum(UIImage *image, id completionTarget, SEL completionSelector, void *contextInfo);

//只能调用这个方法
 - (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo;


//Swfit2.0中要改变这个方法 - (void)image:(UIImage *)image  didFinishSavingWithError:(NSError *)error  contextInfo:(void *)contextInfo;

改变方法为：

       //解释：didFinishSavingWithError为外部参数。 在OC中有两个contextInfo ，Swift中自动推断后，删除一个contextInfo.

    @objc private func image(image: UIImage, didFinishSavingWithErrorerror:NSError?,contextInfo:AnyObject) {

        print("保存成功")
    }

调用：

            UIImageWriteToSavedPhotosAlbum(image, self, "image:didFinishSavingWithError:contextInfo:" , nil)