UIPickerView, detect “rolling wheel” start and stop?

Question

I just discovered that if I do the following:

1. Click the button that animates a UIPickerView into my view
2. Quickly start the wheel rolling

Answer 1

Swift 4 (updated) version with extension of @DrainBoy answers

extension UIView  {
 func isScrolling () -> Bool {

    if let scrollView = self as? UIScrollView {
        if  (scrollView.isDragging || scrollView.isDecelerating) {
            return true
        }
    }

    for subview in self.subviews {
        if ( subview.isScrolling() ) {
            return true
        }
    }
    return false
 }
}