Question

到目前为止，我一直在努力实现您可以在下图中看到的左栏按钮项目：

我还没有编写风格，只是获取个人资料图片的基本代码。这是：

let user = FIRAuth.auth()?.currentUser
var profilePicture: UIImageView?

override func viewDidLoad() {
    //left bar button item setup

    if let profileURL = self.user?.photoURL?.absoluteString {
        let profilePictureUrl = NSURL(string: profileURL)
        profilePicture?.af_setImage(withURL: profilePictureUrl as! URL)

        let barButton = UIBarButtonItem(image: profilePicture?.image, landscapeImagePhone: nil, style: .done, target: self, action: #selector(revealBackClicked))
        self.navigationItem.leftBarButtonItem = barButton
    }


}

我正在使用以下功能从firebase检索我的照片：

self.user?.photoURL?.absoluteString

我收到了一个网址，因为我在输出中打印了它。但是，我认为问题是当我在profilePicture变量中设置图像时，因为当我打印出来时，我收到的是nil。

非常感谢任何帮助！

Answer 1

在下载图像时，您尝试将图像设置为UIBarButtonItem的问题。您应下载图像，然后将图像设置为UIBarButtonItem。

let profilePictureUrl = NSURL(string: profileURL)

let downloader = ImageDownloader()
let urlRequest = URLRequest(url: profilePictureUrl)

downloader.download(urlRequest) { response in
    if let image = response.result.value {
        let barButton = UIBarButtonItem(image: image, landscapeImagePhone: nil, style: .done, target: self, action: #selector(revealBackClicked))
        self.navigationItem.leftBarButtonItem = barButton
    }
}

Answer 2

let user = FIRAuth.auth()?.currentUser

override func viewDidLoad() {
    super.viewDidLoad()

    let profilePictureURL = self.user?.photoURL

    DispatchQueue.global().async {
        let data = try? Data(contentsOf: profilePictureURL!)
        DispatchQueue.main.async {
            let button = UIButton.init(type: .custom)
            button.setImage(UIImage(data: data!), for: UIControlState.normal)
            button.layer.cornerRadius = 0.5 * button.bounds.size.width
            button.clipsToBounds = true
            button.addTarget(self, action: #selector(UserGroupsMainViewController.profileButtonPressed), for: UIControlEvents.touchUpInside)
            button.frame = CGRect(x: 0, y: 0, width: 50, height: 50)

            let barButton = UIBarButtonItem(customView: button)
            self.navigationItem.leftBarButtonItem = barButton

        }
    }

}

func profileButtonPressed() {

    print("Show Profile")
}

Answer 3

斯威夫特和核弹

<块引用>

使用 Nuke 为 UIBarButtonItem 将图像插入按钮。

在 ImagePipeline 的帮助下，我们可以轻松获取图像并在任何我们想要的地方使用它。

    guard let url = URL(string: "https://....") else { return }
    ImagePipeline.shared.loadImage(with: url) { result in
        switch result {
        case .success(let data):
            DispatchQueue.main.async {
                let button = UIButton()
                button.setImage(data.image, for: .normal)
                button.layer.cornerRadius = button.bounds.size.height/2
                button.clipsToBounds = true
                button.addTarget(self, action: #selector(profileButtonPressed), for: UIControlEvents.touchUpInside)
                button.frame = CGRect(x: 0, y: 0, width: 50, height: 50)
                
                let barButton = UIBarButtonItem(customView: button)
                self.navigationItem.leftBarButtonItem = barButton
            }
            break
        case .failure:
            break
        }
    }

将URL中的照片放置为导航栏按钮项

3 个答案: