UICollectionViewCell no common ancestor error (NOT duplicate) - ios

Question

class ChatCollectionViewCell: UICollectionViewCell {
var chatView: UIView!
var chatTextView: UITextView!
var isTextFromCurrentUser: Bool = true
var chatViewWidth: CGFloat = 200
override init(frame: CGRect) {
super.init(frame: frame)
chatView = UIView()
chatTextView = UITextView()
contentView.addSubview(chatView)
contentView.addSubview(chatTextView)
setupViews()
}
override func layoutSubviews() {
if isTextFromCurrentUser {
chatView.leftAnchor.constraint(equalTo: self.leftAnchor, constant: 10).isActive = true
chatTextView.leftAnchor.constraint(equalTo: self.leftAnchor, constant: 15).isActive = true
chatTextView.backgroundColor = .white
} else {
chatView.rightAnchor.constraint(equalTo: self.rightAnchor, constant: -10).isActive = true
chatTextView.rightAnchor.constraint(equalTo: self.rightAnchor, constant: -15).isActive = true
chatTextView.backgroundColor = UIColor(r: 157, g: 255, b: 164)
}
chatView.widthAnchor.constraint(equalToConstant: chatViewWidth).isActive = true
chatView.topAnchor.constraint(equalTo: self.topAnchor, constant: 10).isActive = true
chatTextView.widthAnchor.constraint(equalTo: chatView.widthAnchor, constant: -10).isActive = true
chatTextView.topAnchor.constraint(equalTo: chatView.topAnchor, constant: 5).isActive = true
chatView.translatesAutoresizingMaskIntoConstraints = false
chatTextView.translatesAutoresizingMaskIntoConstraints = false
}
func setupViews() {
chatView.backgroundColor = .blue
chatTextView.font = UIFont.systemFont(ofSize: 16)
chatTextView.layer.cornerRadius = 9
chatTextView.clipsToBounds = true
chatTextView.isScrollEnabled = false
}
override func prepareForReuse() {
super.prepareForReuse()
chatView = nil
chatTextView = nil
chatView = UIView()
chatTextView = UITextView()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
(for clarification, I am setting the chatViewWidth and the chatTextView.text property in the ViewController's cellForRow method)
So right now, the error that XCode is giving is the following: "Unable to activate constraint with anchors and because they have no common ancestor. Does the constraint or its anchors reference items in different view hierarchies?"
I looked through many posts regarding common ancestor errors on StackOverflow, but none of the solutions solved my problem.
Which is very confusing.
I tried using breakpoints to analyze what was wrong, but the program crashed after creating around ~14 cells or so. And sometimes it works, but when I add more cells, it will begin crashing. I'm not sure what the issue is--my views are definitely children views of the CollectionViewCell, correct?
Thank you!

Answer 1

This is how i would do it ... well basicy i would set all the stuff in Storyboard and set an Outlet for the widthConstraint ... but to take your code, this should work. But its not testet ... :)
class ChatCollectionViewCell: UICollectionViewCell {
var chatView: UIView!
var chatTextView: UITextView!
var isTextFromCurrentUser: Bool = true {
didSet {
if isTextFromCurrentUser {
NSLayoutConstraint.deactivate(rightAlignmentConstraints)
NSLayoutConstraint.activate(leftAlignmentConstraints)
chatTextView.backgroundColor = .white
} else {
NSLayoutConstraint.deactivate(leftAlignmentConstraints)
NSLayoutConstraint.activate(rightAlignmentConstraints)
chatTextView.backgroundColor = UIColor(r: 157, g: 255, b: 164)
}
}
}
var chatViewWidth: CGFloat = 200 {
didSet {
chatView.widthAnchor.constraint(equalToConstant: chatViewWidth).isActive = true
}
}
private var leftAlignmentConstraints: [NSLayoutConstraint] = []
private var rightAlignmentConstraints: [NSLayoutConstraint] = []
override init(frame: CGRect) {
super.init(frame: frame)
setupViews()
}
func setupViews() {
chatView = UIView()
chatTextView = UITextView()
contentView.addSubview(chatView)
contentView.addSubview(chatTextView)
chatView.translatesAutoresizingMaskIntoConstraints = false
chatTextView.translatesAutoresizingMaskIntoConstraints = false
chatView.backgroundColor = .blue
chatTextView.font = UIFont.systemFont(ofSize: 16)
chatTextView.layer.cornerRadius = 9
chatTextView.clipsToBounds = true
chatTextView.isScrollEnabled = false
leftAlignmentConstraints = [
chatView.leftAnchor.constraint(equalTo: self.leftAnchor, constant: 10),
chatTextView.leftAnchor.constraint(equalTo: self.leftAnchor, constant: 15)
]
rightAlignmentConstraints = [
chatView.rightAnchor.constraint(equalTo: self.rightAnchor, constant: -10),
chatTextView.rightAnchor.constraint(equalTo: self.rightAnchor, constant: -15)
]
chatView.widthAnchor.constraint(equalToConstant: chatViewWidth).isActive = true
chatView.topAnchor.constraint(equalTo: self.topAnchor, constant: 10).isActive = true
chatTextView.widthAnchor.constraint(equalTo: chatView.widthAnchor, constant: -10).isActive = true
chatTextView.topAnchor.constraint(equalTo: chatView.topAnchor, constant: 5).isActive = true
NSLayoutConstraint.activate(leftAlignmentConstraints)
}
override func prepareForReuse() {
super.prepareForReuse()
chatTextView.text = ""
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
Good Luck and Happy Coding