UIVisualEffectView上的圆角半径

Question

嗨，我想知道在UIVisualEffectView上设置圆角是否可能？这是我尝试过的代码：

@IBOutlet var blurView: UIVisualEffectView!

var blurLayer : CALayer{
    return blurView.layer
}
override func viewDidLoad() {
    super.viewDidLoad()
    setUpLayer()
    // Do any additional setup after loading the view.
}

func setUpLayer(){
    blurLayer.cornerRadius = 50
}

和

@IBOutlet var blurView: UIVisualEffectView!

override func viewDidLoad() {
    super.viewDidLoad()
    blurView.layer.cornerRadius = 50
    // Do any additional setup after loading the view.
}

它们都不起作用。

- Johan Enstam

---

你尝试过使用“blurView.clipsToBounds = true”吗？ - Mike M

谢谢，运行得非常好！ - Johan Enstam

@MikeM 也许你应该把这个放到答案里？ - Oxcug

Answer 1

在@theMonster的建议下，我正在发布一个之前是评论的内容。

override func viewDidLoad() {
    super.viewDidLoad()
    blurView.layer.cornerRadius = 50
    blurView.clipsToBounds = true
}

- Mike M

Answer 2

在Storyboard中，添加两个用户定义的运行时属性：layer.cornerRadius = 8和layer.masksToBounds = true 或者在代码中实现。

@IBOutlet var blurView: UIVisualEffectView! {
    didSet {
        blurView.layer.cornerRadius = 8
        blurView.layer.masksToBounds = true
    }
}

- amir sheibani

---

你应该[编辑]这个答案并修复格式。很难知道哪些是解释，哪些是代码。 - user1531971

Answer 3

继承自UIVisualEffectView的子类

class PSORoundedVisualEffectView : UIVisualEffectView{

    override func layoutSubviews() {
        super.layoutSubviews()
        updateMaskLayer()
    }

    func updateMaskLayer(){
        let shapeLayer = CAShapeLayer()
        shapeLayer.path = UIBezierPath(roundedRect: self.bounds, cornerRadius: 10).CGPath
        self.layer.mask = shapeLayer
    }
}

用任何您想要的形状替换UIBezierPath。

- the Reverend

---

谢谢！这个很有效。但是制作一个扩展程序会更容易些。 - Henry Ngan

不是这样的，这样更容易。 - Fattie

Answer 4

所有现有的解决方案都不是完美的。

由于UIVisualEffectView通过合成两个子视图内容来实现其视觉效果 - 一个是背景视图，另一个是过滤器视图，因此当您通过掩蔽整个UIVisualEffectView来实现您的角半径时，角落周围会有一些脏色。

为了摆脱这些肮脏的颜色，您只需要遮盖UIVisualEffects的过滤器视图。

private typealias ObjcRawUIVisualEffectViewSelCGRect =
    @convention(c) (UIVisualEffectView, Selector, CGRect) -> Void

private var cornerRadiusKey =
"com.WeZZard.Waxing.UIVisualEffectView-CornerRadius.cornerRadius"

private var needsUpdateMaskLayerKey =
"com.WeZZard.Waxing.UIVisualEffectView-CornerRadius.needsUpdateMaskLayer"

extension UIVisualEffectView {
    public var cornerRadius: CGFloat {
        get {
            if let storedValue = objc_getAssociatedObject(self,
                &cornerRadiusKey)
                as? CGFloat
            {
                return storedValue
            }
            return 0
        }
        set {
            if cornerRadius != newValue {
                objc_setAssociatedObject(self,
                    &cornerRadiusKey,
                    newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
                setNeedsUpdateMaskLayer()
            }
        }
    }

    private var needsUpdateMaskLayer: Bool {
        get {
            if let storedValue = objc_getAssociatedObject(self,
                &needsUpdateMaskLayerKey)
                as? Bool
            {
                return storedValue
            }
            return false
        }
        set {
            objc_setAssociatedObject(self,
                &needsUpdateMaskLayerKey,
                newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
    }


    public override class func initialize() {
        swizzle_setBounds()
    }

    private class func swizzle_setBounds() {
        struct Static {
            static var token: dispatch_once_t = 0
        }

        dispatch_once(&Static.token) {
            let selector: Selector = "setBounds:"

            let method = class_getInstanceMethod(self, selector)

            let imp_original = method_getImplementation(method)

            before_setBounds = unsafeBitCast(imp_original,
                ObjcRawUIVisualEffectViewSelCGRect.self)

            class_replaceMethod(self,
                selector,
                unsafeBitCast(after_setBounds, IMP.self),
                "@:{_struct=CGRect}")
        }
    }

    private func setNeedsUpdateMaskLayer() {
        needsUpdateMaskLayer = true
        NSOperationQueue.mainQueue().addOperationWithBlock { [weak self] _ in
            self?.updateMaskLayerIfNeeded()
        }
    }

    private func updateMaskLayerIfNeeded() {
        if needsUpdateMaskLayer {
            updateMaskLayer()
            needsUpdateMaskLayer = false
        }
    }

    private func updateMaskLayer(){
        var filterViewFound = false
        for each in subviews {
            if each.dynamicType.description()
                .containsString("Filter")
            {
                filterViewFound = true
                let newPath = UIBezierPath(roundedRect: each.bounds,
                    cornerRadius: self.cornerRadius)
                    .CGPath
                if let existedMask = each.layer.mask
                    as? CAShapeLayer
                {
                    existedMask.path = newPath
                } else {
                    let shapeLayer = CAShapeLayer()
                    shapeLayer.path = newPath
                    each.layer.mask = shapeLayer
                }
            } else {
                setNeedsUpdateMaskLayer()
            }
        }
        assert(filterViewFound == true, "Filter view was not found! Check your hacking!")
    }
}

private var before_setBounds: ObjcRawUIVisualEffectViewSelCGRect = { _ in
    fatalError("No implementation found")
}

private let after_setBounds: ObjcRawUIVisualEffectViewSelCGRect = {
    (aSelf, selector, bounds) -> Void in

    let oldBounds = aSelf.bounds

    before_setBounds(aSelf, selector, bounds)

    if oldBounds.size != bounds.size {
        aSelf.setNeedsUpdateMaskLayer()
    }
}

一切都完成了！

- WeZZard