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Swift:UIVisualEffectView,具有圆形顶边和彩色边框

uivisualeffectview mask calayer uiview swift

l30c0d35 · 技术社区 · 6 年前

我试图建立一个圆角视图,但只有左上角和右上角和彩色边框。这是我的观点课:

class PullUpOverview: UIVisualEffectView {

override init(effect: UIVisualEffect?) {
    super.init(effect: effect)

    let maskLayer = CAShapeLayer()
    maskLayer.path = UIBezierPath(roundedRect: bounds,
                                  byRoundingCorners: [.topRight, .topLeft],
                                  cornerRadii: CGSize(width: 25, height: 25)).cgPath
    layer.mask = maskLayer

    let borderLayer = CAShapeLayer()
    borderLayer.frame = bounds
    borderLayer.path = maskLayer.path
    borderLayer.lineWidth = 1
    borderLayer.strokeColor = UIColor.gray.cgColor
    borderLayer.fillColor = UIColor.clear.cgColor
    layer.addSublayer(borderLayer)
}

required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}
}

我将视图添加到 viewDidLoad 像这样的方法( overviewRect

let overview = PullUpOverview(effect: UIBlurEffect(style: UIBlurEffect.Style.extraLight))
overview.frame = overviewRect
self.mapView.addSubview(overview)

但是如果我添加视图,什么都不会出现。如果我改变主意 PullUpOverview 视图加载 UIVisualEffectView

let overview = PullUpOverview(frame: overviewRect)
self.mapView.addSubview(overview)

所以我需要做什么改变才能得到一个UIVisualEffectView,它有两个圆角(都是顶角)和一个边界层?

1 回复 | 直到 6 年前

Kamran 6 年前

这个 size zero 对于 bounds 所以这两层都不可见。您可以引入如下自定义初始值设定项,

class PullUpOverview: UIVisualEffectView {

    init(effect: UIVisualEffect?, size: CGSize) {
        super.init(effect: effect)

        let rect = CGRect(origin: .zero, size: size)

        let maskLayer = CAShapeLayer()
        maskLayer.path = UIBezierPath(roundedRect: rect,
                                      byRoundingCorners: [.topRight, .topLeft],
                                      cornerRadii: CGSize(width: 25, height: 25)).cgPath
        maskLayer.frame = rect
        layer.mask = maskLayer

        let borderLayer = CAShapeLayer()
        borderLayer.frame = rect
        borderLayer.path = maskLayer.path
        borderLayer.lineWidth = 1
        borderLayer.strokeColor = UIColor.yellow.cgColor
        borderLayer.fillColor = UIColor.clear.cgColor
        layer.addSublayer(borderLayer)
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

现在你可以初始化并添加这个 view 作为,

let overviewRect = CGRect(origin: CGPoint(x: 100, y: 200), size: CGSize(width: 200, height: 200))
let overview = PullUpOverview(effect: UIBlurEffect(style: .dark), size: overviewRect.size)
overview.frame = overviewRect
self.view.addSubview(overview)