swift - 如何以编程方式快速使 UItabbar 图像四舍五入

Question

我想创建如下图所示的东西你能帮我任何代码如何使它四舍五入吗感谢您的帮助!

Answer 1

我认为你需要

1. (可选)如果图像大于标准条形按钮图像大小，则调整图像大小)
2. 使图像变圆

在将其用作 UItabBarItem 图像之前。下面是具有这两个功能的 UIImage 的扩展:

extension UIImage{
var roundedImage: UIImage {
    let rect = CGRect(origin:CGPoint(x: 0, y: 0), size: self.size)
    UIGraphicsBeginImageContextWithOptions(self.size, false, 1)
    UIBezierPath(
        roundedRect: rect,
        cornerRadius: self.size.height
        ).addClip()
    self.draw(in: rect)
    return UIGraphicsGetImageFromCurrentImageContext()!
}
func resizedImage(newWidth: CGFloat) -> UIImage {
    let scale = newWidth / self.size.width
    let newHeight = self.size.height * scale
    UIGraphicsBeginImageContext(CGSize(width: newWidth, height: newHeight))
    self.draw(in: CGRect(x: 0, y: 0, width: newWidth, height: newHeight))
    let newImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    return newImage!
}
}

示例用法:

let barImage: UIImage = UIImage(named: "avatar_copy.png")!.resizedImage(newWidth: 40).roundedImage.withRenderingMode(.alwaysOriginal)
let roundTabBar = UITabBarItem(title: nil, image: barImage.withRenderingMode(.alwaysOriginal), selectedImage: barImage)        
self.bottomTabbar.items = [roundTabBar]