let blur = UIBlurEffect(style: .Light)
let blurView = UIVisualEffectView(effect: blur)
blurView.frame = findATeamLabel.bounds
findATeamLabel.addSubview(blurView)
模糊标签，以实现文本的模糊/非模糊。通过CoreImage模糊滤镜，你可以将标签的文本进行模糊处理，并在标签上方显示该图像。class BlurredLabel: UILabel {
func blur(_ blurRadius: Double = 2.5) {
let blurredImage = getBlurryImage(blurRadius)
let blurredImageView = UIImageView(image: blurredImage)
blurredImageView.translatesAutoresizingMaskIntoConstraints = false
blurredImageView.tag = 100
blurredImageView.contentMode = .center
blurredImageView.backgroundColor = .white
addSubview(blurredImageView)
NSLayoutConstraint.activate([
blurredImageView.centerXAnchor.constraint(equalTo: centerXAnchor),
blurredImageView.centerYAnchor.constraint(equalTo: centerYAnchor)
])
}
func unblur() {
subviews.forEach { subview in
if subview.tag == 100 {
subview.removeFromSuperview()
}
}
}
private func getBlurryImage(_ blurRadius: Double = 2.5) -> UIImage? {
UIGraphicsBeginImageContext(bounds.size)
layer.render(in: UIGraphicsGetCurrentContext()!)
guard let image = UIGraphicsGetImageFromCurrentImageContext(),
let blurFilter = CIFilter(name: "CIGaussianBlur") else {
UIGraphicsEndImageContext()
return nil
}
UIGraphicsEndImageContext()
blurFilter.setDefaults()
blurFilter.setValue(CIImage(image: image), forKey: kCIInputImageKey)
blurFilter.setValue(blurRadius, forKey: kCIInputRadiusKey)
var convertedImage: UIImage?
let context = CIContext(options: nil)
if let blurOutputImage = blurFilter.outputImage,
let cgImage = context.createCGImage(blurOutputImage, from: blurOutputImage.extent) {
convertedImage = UIImage(cgImage: cgImage)
}
return convertedImage
}
}
提示：请根据您的要求改进此组件（例如，如果已经模糊，请避免再次模糊，或者如果文本更改，则可以删除当前的模糊并重新应用模糊）。
另外需要考虑的是，将模糊应用于某些内容会导致其内容溢出，因此要么将clipsToBounds=false应用于BlurredLabel，要么找到其他实现视觉效果的方法，以避免模糊图像看起来不在与之前未模糊的标签文本相同的位置。
要使用它，您可以简单地创建一个BlurredLabel：
let blurredLabel = BlurredLabel()
blurredLabel.text = "56.00 €"
在点击某个按钮时，您可以通过blurredLabel.blur()进行模糊操作，并通过blurredLabel.unblur()取消模糊。
使用blur()方法并将模糊半径设为2.5，可以获得以下输出：
要了解更多高斯模糊的信息，可以查阅维基百科上的相关文章：https://en.wikipedia.org/wiki/Gaussian_blur
UIGraphicsGetCurrentContext()！中意外发现了nil值”的错误。 - XY LiSwift 5 - 将模糊效果作为UIView扩展
extension UIView {
struct BlurableKey {
static var blurable = "blurable"
}
func blur(radius: CGFloat) {
guard superview != nil else { return }
UIGraphicsBeginImageContextWithOptions(CGSize(width: frame.width, height: frame.height), false, 1)
layer.render(in: UIGraphicsGetCurrentContext()!)
let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
guard
let blur = CIFilter(name: "CIGaussianBlur"),
let image = image
else {
return
}
blur.setValue(CIImage(image: image), forKey: kCIInputImageKey)
blur.setValue(radius, forKey: kCIInputRadiusKey)
let ciContext = CIContext(options: nil)
let boundingRect = CGRect(
x:0,
y: 0,
width: frame.width,
height: frame.height
)
guard
let result = blur.value(forKey: kCIOutputImageKey) as? CIImage,
let cgImage = ciContext.createCGImage(result, from: boundingRect)
else {
return
}
let blurOverlay = UIImageView()
blurOverlay.frame = boundingRect
blurOverlay.image = UIImage(cgImage: cgImage)
blurOverlay.contentMode = .left
addSubview(blurOverlay)
objc_setAssociatedObject(
self,
&BlurableKey.blurable,
blurOverlay,
objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN
)
}
func unBlur() {
guard
let blurOverlay = objc_getAssociatedObject(self, &BlurableKey.blurable) as? UIImageView
else {
return
}
blurOverlay.removeFromSuperview()
objc_setAssociatedObject(
self,
&BlurableKey.blurable,
nil,
objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN
)
}
var isBlurred: Bool {
return objc_getAssociatedObject(self, &BlurableKey.blurable) is UIImageView
}
}
findATeamLabel.sendSubviewToBack(blurView)
我通过在标签后面添加一个视图（标签不在该视图内，而是在其前面）来使其工作。然后我将模糊效果添加到视图上... 我仍然认为应该有一种更简单的方法。
对我来说，这些答案都不起作用。被接受的答案不能处理不同颜色背景或标签颜色不同于黑色的情况。根据评论，它跳到了另一个问题，但是答案使得模糊移动到右侧很多。因此，在阅读一些内容后，我调整了结果图像上的CGRect。
class BlurredLabel: UILabel {
var isBlurring = false {
didSet {
setNeedsDisplay()
}
}
var blurRadius: Double = 8 {
didSet {
blurFilter?.setValue(blurRadius, forKey: kCIInputRadiusKey)
}
}
lazy var blurFilter: CIFilter? = {
let blurFilter = CIFilter(name: "CIGaussianBlur")
blurFilter?.setDefaults()
blurFilter?.setValue(blurRadius, forKey: kCIInputRadiusKey)
return blurFilter
}()
override init(frame: CGRect) {
super.init(frame: frame)
layer.isOpaque = false
layer.needsDisplayOnBoundsChange = true
layer.contentsScale = UIScreen.main.scale
layer.contentsGravity = .center
isOpaque = false
isUserInteractionEnabled = false
contentMode = .redraw
}
required init?(coder: NSCoder) {
super.init(coder: coder)
}
override func display(_ layer: CALayer) {
let bounds = layer.bounds
guard !bounds.isEmpty && bounds.size.width < CGFloat(UINT16_MAX) else {
layer.contents = nil
return
}
UIGraphicsBeginImageContextWithOptions(layer.bounds.size, layer.isOpaque, layer.contentsScale)
if let ctx = UIGraphicsGetCurrentContext() {
self.layer.draw(in: ctx)
var image = UIGraphicsGetImageFromCurrentImageContext()?.cgImage
if isBlurring {
blurFilter?.setValue(CIImage(cgImage: image!), forKey: kCIInputImageKey)
let ciContext = CIContext(cgContext: ctx, options: nil)
if let blurOutputImage = blurFilter?.outputImage {
let boundingRect = CGRect(
x:0,
y: blurOutputImage.extent.minY,
width: blurOutputImage.extent.width,
height: blurOutputImage.extent.height
)
image = ciContext.createCGImage(blurOutputImage, from: boundingRect)
}
}
layer.contents = image
}
UIGraphicsEndImageContext()
}
}