Adding blur effect to background in swift

Question

I am setting a background image to view controller. But also i want to add blur effect to this background. How can I do this?

I am setting background with following

Answer 1

For Swift 3 (iOS 10.0 and 8.0)

var darkBlur:UIBlurEffect = UIBlurEffect()

if #available(iOS 10.0, *) { //iOS 10.0 and above
    darkBlur = UIBlurEffect(style: UIBlurEffectStyle.prominent)//prominent,regular,extraLight, light, dark
} else { //iOS 8.0 and above
  darkBlur = UIBlurEffect(style: UIBlurEffectStyle.dark) //extraLight, light, dark
}
let blurView = UIVisualEffectView(effect: darkBlur)
blurView.frame = self.view.frame //your view that have any objects
blurView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
view.addSubview(blurView)

Answer 2

U can also use CoreImage to create blurred image with dark effect

1. Make snapshot for image

   func snapShotImage() -> UIImage {
       UIGraphicsBeginImageContext(self.frame.size)
       if let context = UIGraphicsGetCurrentContext() {
           self.layer.renderInContext(context)
           let image = UIGraphicsGetImageFromCurrentImageContext()
           UIGraphicsEndImageContext()
           return image
       }
   
       return UIImage()
   }
   

2. Apply CoreImage Filters as u wish with

   private func bluredImage(view:UIView, radius:CGFloat = 1) -> UIImage {
   let image = view.snapShotImage()
   
   if let source = image.CGImage {
       let context = CIContext(options: nil)
       let inputImage = CIImage(CGImage: source)
   
       let clampFilter = CIFilter(name: "CIAffineClamp")
       clampFilter?.setDefaults()
       clampFilter?.setValue(inputImage, forKey: kCIInputImageKey)
   
       if let clampedImage = clampFilter?.valueForKey(kCIOutputImageKey) as? CIImage {
           let explosureFilter = CIFilter(name: "CIExposureAdjust")
           explosureFilter?.setValue(clampedImage, forKey: kCIInputImageKey)
           explosureFilter?.setValue(-1.0, forKey: kCIInputEVKey)
   
           if let explosureImage = explosureFilter?.valueForKey(kCIOutputImageKey) as? CIImage {
               let filter = CIFilter(name: "CIGaussianBlur")
               filter?.setValue(explosureImage, forKey: kCIInputImageKey)
               filter?.setValue("\(radius)", forKey:kCIInputRadiusKey)
   
               if let result = filter?.valueForKey(kCIOutputImageKey) as? CIImage {
                   let bounds = UIScreen.mainScreen().bounds
                   let cgImage = context.createCGImage(result, fromRect: bounds)
                   let returnImage = UIImage(CGImage: cgImage)
                   return returnImage
               }
           }
       }
   }
   return UIImage()
   }
   

Answer 3

This worked for me on Swift 5

let blurredView = UIVisualEffectView(effect: UIBlurEffect(style: .light))
blurredView.frame = self.view.bounds
backgroundimage.addSubview(blurredView)

Answer 4

I have tested this code and it's working fine:

let blurEffect = UIBlurEffect(style: UIBlurEffect.Style.dark)
let blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.frame = view.bounds
blurEffectView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
view.addSubview(blurEffectView)

For Swift 3.0:

let blurEffect = UIBlurEffect(style: UIBlurEffectStyle.dark)
let blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.frame = view.bounds
blurEffectView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
view.addSubview(blurEffectView)

For Swift 4.0:

let blurEffect = UIBlurEffect(style: UIBlurEffect.Style.dark)
let blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.frame = view.bounds
blurEffectView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
view.addSubview(blurEffectView)

Here you can see result:

Or you can use this lib for that:

https://github.com/FlexMonkey/Blurable

Answer 5

This one always keeps the right frame:

public extension UIView {

    @discardableResult
    public func addBlur(style: UIBlurEffect.Style = .extraLight) -> UIVisualEffectView {
        let blurEffect = UIBlurEffect(style: style)
        let blurBackground = UIVisualEffectView(effect: blurEffect)
        addSubview(blurBackground)
        blurBackground.translatesAutoresizingMaskIntoConstraints = false
        blurBackground.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
        blurBackground.topAnchor.constraint(equalTo: topAnchor).isActive = true
        blurBackground.leadingAnchor.constraint(equalTo: leadingAnchor).isActive = true
        blurBackground.trailingAnchor.constraint(equalTo: trailingAnchor).isActive = true
        return blurBackground
    }
}