BottomSheetPresentationController_9.swift

private func didGestureTranslationChange(_ translation: CGPoint) {
    guard let presentedView = presentedView else {
        return
    }
    
    let translationY = max(0, translation.y)
    presentedView.transform = CGAffineTransform(translationX: 0, y: translationY)
    
    let progress = translationY / presentedView.frame.height
    transitioningDelegate?.transition.update(progress)
}