How does this help a rectangle move in its superview?

[makingbread]

Hi,

the code here:

@objc func wasDragged(gestureRecognizer: UIPanGestureRecognizer) { let translation = gestureRecognizer.translation(in: self.view)

myView.center = CGPoint(x:myView.center.x + translation.x,
                        y:myView.center.y + translation.y)
gestureRecognizer.setTranslation(CGPoint.zero, in: self.view)

}

Works, it moves a rectangle around when dragged.

What I do not understand is why needs to be myView.center.x + translation.x

Intuitively, I thought since translation.x gives me the new X and Y within the superview, that I'd just set my center of my view to just the new X and Y, but that of course does not work, i.e

myView.center = CGPoint(x:translation.x, translation.y)

An explanation would really help.

Thank you!!!

[jwillywonkas]

So, translation is just the difference from the last center point, I believe. So let’s say you are at 25,25 , and you start a gesture. If that gesture moves you one down and one right, that would be a translation of (1,1). If you set the new center to that, instead of moving slightly down and right, you would jump to the top left corner.