iosswiftuicontextmenuinteractionuicontextmenuconfiguration

How to hide UIContextMenuInteraction/UITargetedPreview black background?


I want to add UIContextMenuInteraction to a UIView with some transparent parts. When user interact with this view, iOS shows this view with a black background.

enter image description here

Is it possible to make those parts transparent or change the color?


Solution

  • Finally I found the solution! You need to implement this function if you want to show a custom curved:

    func contextMenuInteraction(_ interaction: UIContextMenuInteraction, previewForHighlightingMenuWithConfiguration configuration: UIContextMenuConfiguration) -> UITargetedPreview? {
        let previewTarget = UIPreviewTarget(container: self.view, center: center)
        let previewParams = UIPreviewParameters()
    
        var topLeft : CGFloat = 8
        var topRight : CGFloat = 9
        var bottomRight : CGFloat = 10
        var bottomLeft : CGFloat = 11
    
        let topLeftRadius = CGSize(width: topLeft, height: topLeft)
        let topRightRadius = CGSize(width: topRight, height: topRight)
        let bottomLeftRadius = CGSize(width: bottomLeft, height: bottomLeft)
        let bottomRightRadius = CGSize(width: bottomRight, height: bottomRight)
    
        previewParams.visiblePath = UIBezierPath(shouldRoundRect: TheExactRectYouWantToShow, topLeftRadius: topLeftRadius, topRightRadius: topRightRadius, bottomLeftRadius: bottomLeftRadius, bottomRightRadius: bottomRightRadius)
        let targetView = UITargetedPreview(view: YourViewToShow, parameters: previewParams, target: previewTarget)
        return targetView
    }
    

    Here we are drawing a UIBezierPath around our custom shaped view. To do this you may need this extension too:

    extension UIBezierPath {
    convenience init(shouldRoundRect rect: CGRect, topLeftRadius: CGSize = .zero, topRightRadius: CGSize = .zero, bottomLeftRadius: CGSize = .zero, bottomRightRadius: CGSize = .zero){
    
        self.init()
    
        let path = CGMutablePath()
    
        let topLeft = rect.origin
        let topRight = CGPoint(x: rect.maxX, y: rect.minY)
        let bottomRight = CGPoint(x: rect.maxX, y: rect.maxY)
        let bottomLeft = CGPoint(x: rect.minX, y: rect.maxY)
    
        if topLeftRadius != .zero{
            path.move(to: CGPoint(x: topLeft.x+topLeftRadius.width, y: topLeft.y))
        } else {
            path.move(to: CGPoint(x: topLeft.x, y: topLeft.y))
        }
    
        if topRightRadius != .zero{
            path.addLine(to: CGPoint(x: topRight.x-topRightRadius.width, y: topRight.y))
            path.addCurve(to:  CGPoint(x: topRight.x, y: topRight.y+topRightRadius.height), control1: CGPoint(x: topRight.x, y: topRight.y), control2:CGPoint(x: topRight.x, y: topRight.y+topRightRadius.height))
        } else {
             path.addLine(to: CGPoint(x: topRight.x, y: topRight.y))
        }
    
        if bottomRightRadius != .zero{
            path.addLine(to: CGPoint(x: bottomRight.x, y: bottomRight.y-bottomRightRadius.height))
            path.addCurve(to: CGPoint(x: bottomRight.x-bottomRightRadius.width, y: bottomRight.y), control1: CGPoint(x: bottomRight.x, y: bottomRight.y), control2: CGPoint(x: bottomRight.x-bottomRightRadius.width, y: bottomRight.y))
        } else {
            path.addLine(to: CGPoint(x: bottomRight.x, y: bottomRight.y))
        }
    
        if bottomLeftRadius != .zero{
            path.addLine(to: CGPoint(x: bottomLeft.x+bottomLeftRadius.width, y: bottomLeft.y))
            path.addCurve(to: CGPoint(x: bottomLeft.x, y: bottomLeft.y-bottomLeftRadius.height), control1: CGPoint(x: bottomLeft.x, y: bottomLeft.y), control2: CGPoint(x: bottomLeft.x, y: bottomLeft.y-bottomLeftRadius.height))
        } else {
            path.addLine(to: CGPoint(x: bottomLeft.x, y: bottomLeft.y))
        }
    
        if topLeftRadius != .zero{
            path.addLine(to: CGPoint(x: topLeft.x, y: topLeft.y+topLeftRadius.height))
            path.addCurve(to: CGPoint(x: topLeft.x+topLeftRadius.width, y: topLeft.y) , control1: CGPoint(x: topLeft.x, y: topLeft.y) , control2: CGPoint(x: topLeft.x+topLeftRadius.width, y: topLeft.y))
        } else {
            path.addLine(to: CGPoint(x: topLeft.x, y: topLeft.y))
        }
    
        path.closeSubpath()
        cgPath = path
    }
    

    And this:

    extension UIView {
    
    func roundCorners(topLeft: CGFloat = 0, topRight: CGFloat = 0, bottomLeft: CGFloat = 0, bottomRight: CGFloat = 0) {//(topLeft: CGFloat, topRight: CGFloat, bottomLeft: CGFloat, bottomRight: CGFloat) {
        let topLeftRadius = CGSize(width: topLeft, height: topLeft)
        let topRightRadius = CGSize(width: topRight, height: topRight)
        let bottomLeftRadius = CGSize(width: bottomLeft, height: bottomLeft)
        let bottomRightRadius = CGSize(width: bottomRight, height: bottomRight)
        let maskPath = UIBezierPath(shouldRoundRect: bounds, topLeftRadius: topLeftRadius, topRightRadius: topRightRadius, bottomLeftRadius: bottomLeftRadius, bottomRightRadius: bottomRightRadius)
        let shape = CAShapeLayer()
        shape.path = maskPath.cgPath
        layer.mask = shape
    }
    }