I am new in ios developement.i need to show scratch-card effect for an iPhone app after scratches if coupon number is visible i need to show alert message How can i do this?.i have download sample code from iPhone - Scratch and Win Example and also i have done showing below screen and scratches also works fine
if UILabel text is visible i want to show alert message How can i do this?
i have attached screen shot for your refference
i Found very nice Github example please take a look this and impliment as par you need hope this helps to you my Frnd.
CGScratch This is same thing that you want to apply.
review the code and check the visible area of Number else check che scration overImage is tatally removed of not if remove then show Alert.
A simple UIImageView subclass that allows your UIImageView become a scratch card.
In your storyboard or xib set custom class of your UIImageView that represents your scratch image to ScratchCardImageView. Change lineType or lineWidth to change the appearance of the scratch lines.
Download example
Swift 3:
import UIKit
class ScratchCardImageView: UIImageView {
private var lastPoint: CGPoint?
var lineType: CGLineCap = .square
var lineWidth: CGFloat = 20.0
override func awakeFromNib() {
super.awakeFromNib()
isUserInteractionEnabled = true
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
guard let touch = touches.first else {
return
}
lastPoint = touch.location(in: self)
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
guard let touch = touches.first, let point = lastPoint else {
return
}
let currentLocation = touch.location(in: self)
eraseBetween(fromPoint: point, currentPoint: currentLocation)
lastPoint = currentLocation
}
func eraseBetween(fromPoint: CGPoint, currentPoint: CGPoint) {
UIGraphicsBeginImageContext(self.frame.size)
image?.draw(in: self.bounds)
let path = CGMutablePath()
path.move(to: fromPoint)
path.addLine(to: currentPoint)
let context = UIGraphicsGetCurrentContext()!
context.setShouldAntialias(true)
context.setLineCap(lineType)
context.setLineWidth(lineWidth)
context.setBlendMode(.clear)
context.addPath(path)
context.strokePath()
image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
}
}
Updated
With this solution touch events will be tracked only inside the UIImageView bounds. If you need touch events to start already outside your scratchcard, see ScratchCardTouchContainer example
