使用AlamofireImage Swift无法显示缓存的图像

Question

使用ImagaCache中的AutoPurgingImageCache()来实施AlamofireImage

let imageCache = AutoPurgingImageCache()
var urlRequest: URLRequest?
var avatarImage = UIImage(named: "User-logo")!

func setupProfileView(user: AppUser) {
    
    if let profilePicture = user.profilePicture,
        let url = URL(string: profilePicture) {
        
        urlRequest = URLRequest(url: url)
        
        if let request = urlRequest {
            // Add
            imageCache.add(avatarImage, for: request, withIdentifier: "userProfileImage")
            
            // Fetch
            let cachedAvatarImage = imageCache.image(for: request, withIdentifier: "userProfileImage")
            
            userImageView.image = cachedAvatarImage
        }
        
    }
}

问题是userImageView始终显示avatarImage而不是从URL加载的图像

谢谢！