Swift: How to pull out CGPoint number from Override func of touch? - ios

Question

I am using the codes shown below for letting user to touch and draw. During touching it, user always leaves CGPoint or coordinates of his/her first and last touch.
var lastPoint: CGPoint!
var firstPoint: CGPoint!
var swiped: Bool!
var allowTouches = true
override func touchesBegan(touches: Set<UITouch>,
withEvent event: UIEvent?) {
guard allowTouches else {
return
}
swiped = false
if let touch = touches.first {
lastPoint = touch.locationInView(self.imageView)
firstPoint = lastPoint
}
}
override func touchesMoved(touches: Set<UITouch>,
withEvent event: UIEvent?) {
guard allowTouches else {
return
}
swiped = true;
if let touch = touches.first {
let currentPoint = touch.locationInView(imageView)
UIGraphicsBeginImageContext(self.imageView.frame.size)
self.imageView.image?.drawInRect(CGRectMake(0, 0, self.imageView.frame.size.width, self.imageView.frame.size.height))
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y)
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), currentPoint.x, currentPoint.y)
CGContextSetLineCap(UIGraphicsGetCurrentContext(),CGLineCap.Round)
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 5.0)
CGContextStrokePath(UIGraphicsGetCurrentContext())
self.imageView.image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
lastPoint = currentPoint
}
}
As you can see in the code that firstPoint saves the coordinates when user touches the screen and after swiping and then removing the touch, lastPoint saves the coordinates.
My question: how can I get those two coordinates(firstPoint and lastPoint) as return from override func? so that I can use these two values for other calculations outside override func.

Answer 1

use
override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?)
method to calculate the lastPoint of touch when user picks his finger. Since you have declared them as the var and global variables therefore you can use them in any function(method) of the class. Just calculate the difference between the lastPoint and firstPoint and you will get the distance.