Naive dragging

naivedragging.swift

func setupGestureRecognizer() {
    let gesture = UIPanGestureRecognizer(target: self, action: #selector(wasDragged(gesture:)))
    addGestureRecognizer(gesture)
    isUserInteractionEnabled = true
}

@objc func wasDragged(gesture: UIPanGestureRecognizer) {
    if gesture.state == .began || gesture.state == .changed {
        let translation = gesture.translation(in: superview!)
        guard let currentPosition = currentSnapPosition else { return }
        frame.origin = CGPoint(x: currentPosition.x + translation.x, y: currentPosition.y + translation.y)
    }
        
    if gesture.state == .ended {
        
        let nearestCornerPosition = nearestCorner(to: frame.origin)
        UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 100, initialSpringVelocity: 30, options: [.curveEaseOut, .allowUserInteraction], animations: {
            self.frame.origin = nearestCornerPosition
        }, completion: nil)
    }
}