Swift autolayout : constraints in sub-view not working - ios

Question

I am trying to set up a view with two collection views and a view on the center , which in turn has elements inside it.
I have been trying to set constraints using visual format like this :
func setupViews() {
self.view.addSubview(playGroundView)
self.view.addSubview(firstCollectionView)
self.view.addSubview(secondCollectionView)
self.playGroundView.backgroundColor = UIColor.clear
aTextView.backgroundColor = UIColor.yellow
titleTextView.backgroundColor = UIColor.green
searchBar?.backgroundColor = UIColor.darkGray
if #available(iOS 9.0, *) {
playGroundView.topAnchor.constraint(equalTo: topLayoutGuide.bottomAnchor).isActive = true
firstCollectionView.topAnchor.constraint(equalTo: topLayoutGuide.bottomAnchor).isActive = true
secondCollectionView.topAnchor.constraint(equalTo: topLayoutGuide.bottomAnchor).isActive = true
} else {
// Fallback on earlier versions
}
self.playGroundView.addSubview(publishButton)
self.playGroundView.addSubview(searchBar!)
self.playGroundView.addSubview(aTextView)
self.playGroundView.addSubview(titleTextView)
publishButton.addConstraint(NSLayoutConstraint(item: publishButton, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: 44))
aTextView.addConstraint(NSLayoutConstraint(item: aTextView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: 44))
titleTextView.addConstraint(NSLayoutConstraint(item: titleTextView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: 44))
searchBar!.addConstraint(NSLayoutConstraint(item: searchBar!, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: 44))
self.playGroundView.addConstraintsWithFormat("V:[v0]-2-|", views: publishButton)
self.playGroundView.addConstraintsWithFormat("H:[v0]-2-|", views: publishButton)
self.playGroundView.addConstraintsWithFormat("V:|-2-[v0(44)]", views: searchBar!)
self.view.bringSubview(toFront: aTextView)
self.playGroundView.layoutIfNeeded()
self.playGroundView.layoutSubviews()
self.view.addConstraintsWithFormat("H:|-8-[v0(100)][v1][v2(100)]-8-|", views: secondCollectionView,playGroundView,firstCollectionView)
self.view.addConstraintsWithFormat("V:[v0]-2-|", views: playGroundView)
self.view.addConstraintsWithFormat("V:[v0]-2-|", views: secondCollectionView)
self.view.addConstraintsWithFormat("V:[v0]-2-|", views: firstCollectionView)
if(self.isCreate){
self.titleTextView.text = self.recipeDictionary?.value(forKey: "recipeName") as! String!
}
}
// Function to set constraints
func addConstraintsWithFormat(_ format: String, views: UIView...) {
var viewsDictionary = [String: UIView]()
for (index,view) in views.enumerated() {
let key = "v\(index)"
viewsDictionary[key] = view
view.translatesAutoresizingMaskIntoConstraints = false
}
addConstraints(NSLayoutConstraint.constraints(withVisualFormat: format, options: NSLayoutFormatOptions(), metrics: nil, views: viewsDictionary))
}
I don't see the elements inside the sub-view (playGroundView) being rendered. Can someone please suggest what am I doing wrong here ?

Answer 1

I would try the following to debug:
Temporarily set a solid background color to playGroundView instead of UIColor.clear and run it to make playGroundView is having a correct size and position.
Temporarily set borders to the missing subviews and run it to see if the views are even within the playGroundView bounds. Alternatively, you can also run the code, go to Xcode > Debug > View Debugging > Capture View Hierarchy
Set translatesAutoresizingMaskIntoConstraints = false for publishButton, searchBar, etc before adding to playGroundView. While it is not wrong to perform that in your helper function addConstraintsWithFormat, there is no need to make that call multiple times.