如何在 iOS Swift 中将圆形头像图片（来自 url 字符串）设置为 UIBarButton 项

Question

您好，我正在开发一个 iOS Swift 项目，在该项目中，我想在导航栏中将用户个人资料图片显示为圆形。我尝试了很多示例代码，但它没有制作圆角曲线。请帮帮我。

这些代码我都试过了，

var image = UIImage()
if let userImage = UserProfile.image {
   let imageUrl = self.dmcCommon.convertStringToImageURL(url: userImage)
   let data = (try? Data(contentsOf: imageUrl as URL))!
   image = UIImage(data: data)!
} else {
   image = UIImage(named: "Me")!
}

let v = UIImageView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
v.image = image
v.layer.masksToBounds = true
v.layer.cornerRadius = 20

let rightBtn = UIBarButtonItem(customView: v)
self.navigationItem.rightBarButtonItem = rightBtn

结果是这样的， 这里的图像没有变圆，它也没有像我给出的那样占据全宽。

后来我尝试了另一种解决方案，即，

let button = UIButton()
button.frame = CGRect(x: 0, y: 0, width: 30, height: 30)
var image = UIImage()
if let userImage = UserProfile.image {
   let imageUrl = self.dmcCommon.convertStringToImageURL(url: userImage)
   let data = (try? Data(contentsOf: imageUrl as URL))!
   image = UIImage(data: data)!
} else {
   image = UIImage(named: "Me")!
}
UIGraphicsBeginImageContextWithOptions(button.frame.size, false, image.scale)
let rect  = CGRect(x:0, y:0, width:button.frame.size.width, height:button.frame.size.height)
UIBezierPath(roundedRect: rect, cornerRadius: rect.width/2).addClip()
image.draw(in: rect)
let newImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()

button.addTarget(self, action:#selector(self.navToMe), for: UIControl.Event.touchUpInside)
let color = UIColor(patternImage: newImage)
button.backgroundColor = color
button.layer.cornerRadius = 0.5 * button.bounds.size.width
let barButton = UIBarButtonItem()
barButton.customView = button
self.navigationItem.rightBarButtonItems = [notificationButton, barButton]

结果是，

在第二种解决方案中，它可以工作，但图像正在像镜像一样重绘。请帮助我如何在 UIBarButtonItems 中放置圆形头像。

Answer 1

试试这个

    let frame = CGRect(x: 0, y: 0, width: 30, height: 30)
    let customView = UIView(frame: frame)
    let imageView = UIImageView(image: UIImage(named: "turtle"))
    imageView.frame = frame
    imageView.layer.cornerRadius = imageView.frame.height * 0.5
    imageView.layer.masksToBounds = true
    customView.addSubview(imageView)
    navigationItem.rightBarButtonItems = [
        UIBarButtonItem(systemItem: .action), UIBarButtonItem(customView: customView)
    ]

使用你的 UIImage(data:) 构造函数代替 UIImage(name:)

Answer 2

我使用了以下方法，

let button = UIButton(type: .system)
button.frame = CGRect(x: 0, y: 0, width: 30, height: 30)
button.layer.cornerRadius = 15
button.clipsToBounds = true
button.imageView?.contentMode = .scaleAspectFit

let imageData = try? Data(contentsOf: URL(string : "https://www.w3schools.com/howto/img_avatar.png")!)

if let imageData = imageData , let image =  UIImage(data: imageData)?.resizeImage(to: button.frame.size) {
    button.setBackgroundImage(image, for: .normal)
}
navigationItem.rightBarButtonItem = UIBarButtonItem(customView: button)

调整图片大小

extension UIImage {
    func resizeImage(to size: CGSize) -> UIImage {
       return UIGraphicsImageRenderer(size: size).image { _ in
           draw(in: CGRect(origin: .zero, size: size))
    }
}}

在上面的例子中，我使用Data(contentsOf: URL)从互联网加载图像，但最好异步获取图像。更多详情请查看this。

Answer 3

您不需要自定义按钮或图像视图。并且不要使用圆角。只需将目标图像绘制成所需大小并裁剪为圆形并将其用作条形按钮项的image。