Scrollview not scrolling / Trying to add view to bottom of content - swift

Question

So I've added a scrollview to my view controller programmatically and added some views.
func setupScrollView() {
view.addSubview(scrollView)
scrollView.addSubview(contentView)
scrollView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
scrollView.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true
scrollView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
scrollView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
contentView.centerXAnchor.constraint(equalTo: scrollView.centerXAnchor).isActive = true
contentView.widthAnchor.constraint(equalTo: scrollView.widthAnchor).isActive = true
contentView.topAnchor.constraint(equalTo: scrollView.topAnchor).isActive = true
contentView.bottomAnchor.constraint(equalTo: scrollView.bottomAnchor).isActive = true
scrollView.contentSize = contentView.frame.size
}
func addUserAndFollowView(id: String) {
userAndFollow = UserPfAndFollow(id: id)
if let userAndFollow = userAndFollow {
userAndFollow.view.isUserInteractionEnabled = true
contentView.addSubview(userAndFollow.view)
self.contentView.bringSubviewToFront(userAndFollow.view)
userAndFollow.view.translatesAutoresizingMaskIntoConstraints = false
userAndFollow.view.topAnchor.constraint(equalTo: contentView.topAnchor).isActive = true
userAndFollow.view.widthAnchor.constraint(equalTo: contentView.widthAnchor).isActive = true
userAndFollow.view.heightAnchor.constraint(equalToConstant: 100).isActive = true
}
}
func setImageViewConstraints() {
imageView.translatesAutoresizingMaskIntoConstraints = false
imageView.heightAnchor.constraint(equalToConstant: 300).isActive = true
imageView.widthAnchor.constraint(equalToConstant: 300).isActive = true
imageView.centerXAnchor.constraint(equalTo: self.contentView.centerXAnchor).isActive = true
if let userAndFollow = userAndFollow?.view {
imageView.topAnchor.constraint(equalTo: userAndFollow.bottomAnchor, constant: 5).isActive = true
}
}
func addLabelConstraints() {
self.albumTitle?.translatesAutoresizingMaskIntoConstraints = false
self.albumDescription?.translatesAutoresizingMaskIntoConstraints = false
albumTitle?.numberOfLines = 2
albumDescription?.numberOfLines = 3
albumDescription?.adjustsFontSizeToFitWidth = false
albumTitle?.topAnchor.constraint(equalTo: imageView.bottomAnchor, constant: 14).isActive = true
albumTitle?.leadingAnchor.constraint(equalTo: self.contentView.leadingAnchor, constant: 10).isActive = true
albumTitle?.trailingAnchor.constraint(equalTo: self.contentView.trailingAnchor).isActive = true
albumTitle?.leadingAnchor.constraint(equalTo: self.contentView.leadingAnchor, constant: 10).isActive = true
albumDescription?.lineBreakMode = .byTruncatingTail
albumDescription?.topAnchor.constraint(equalTo: albumTitle!.bottomAnchor, constant: 9).isActive = true
albumDescription?.leadingAnchor.constraint(equalTo: self.contentView.leadingAnchor, constant: 10).isActive = true
albumDescription?.trailingAnchor.constraint(equalTo: self.contentView.trailingAnchor).isActive = true
}
All these views show up the way I want them to with the scrollview not scrolling but when I add this next view (which is a tableview in a view controller) at the bottom of the rest of my views it doesn't show up. Possibly why the scrollview isn't scrolling.
func addViewController() {
if let viewController = viewController {
contentView.addSubview(viewController.view)
setVCConstraints()
}
}
func setVCConstraints() {
viewController?.view.translatesAutoresizingMaskIntoConstraints = false
viewController?.view.bottomAnchor.constraint(equalTo: self.contentView.bottomAnchor).isActive = true
viewController?.view.topAnchor.constraint(equalTo: albumDescription!.bottomAnchor, constant: 7).isActive = true
viewController?.view.widthAnchor.constraint(equalTo: self.contentView.widthAnchor).isActive = true
}
What can I do to make this view appear and have my scrollview scroll all the way down this view controller and it's array content and no more or less?

Answer 1

Before you add the view, you have
contentView.centerXAnchor.constraint(equalTo: scrollView.centerXAnchor).isActive = true
contentView.widthAnchor.constraint(equalTo: scrollView.widthAnchor).isActive = true
contentView.topAnchor.constraint(equalTo: scrollView.topAnchor).isActive = true
contentView.bottomAnchor.constraint(equalTo: scrollView.bottomAnchor).isActive = true
scrollView.contentSize = contentView.frame.size
So, of course, the contentView has a size of the scrollView and thus will not scroll. It is the same size.
After you add the view, you have
viewController?.view.bottomAnchor.constraint(equalTo: self.contentView.bottomAnchor).isActive = true
viewController?.view.topAnchor.constraint(equalTo: albumDescription!.bottomAnchor, constant: 7).isActive = true
viewController?.view.widthAnchor.constraint(equalTo: self.contentView.widthAnchor).isActive = true
Note, above, that you define a top bottom and width -- there is no LEFT-TO-RIGHT indication where the viewController.view should start on the horizontal path. This can result in some VERY weird behaviors.
Yet, you STILL don't modify the contentView.contentSize to be any bigger than the scrollView size.
To make something scroll, you need the contentView.contentSize to be bigger than the frame.size.