Having issues with activating constraints programmatically and getting errors - ios

Question

Last night I posted a question on here where I used storyboards to set the constraints. I decided to test it with anchors and do constraints programmatically.
I am getting this error:
Terminating app due to uncaught exception 'NSGenericException',
reason: '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? That's
illegal.'
I know this has to do with views not being a subview of a certain other view however, I have checked it plenty of times and I don't know what to do.
here is the code:
import UIKit
import CoreData
class editViewController: UIViewController {
let screenSize: CGRect = UIScreen.main.bounds
let moContext = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext
var editnotes: addednotes?
let mainbackgroundview: UIView =
{
let view = UIView()
view.backgroundColor = .black
view.alpha = 0.3
return view
}()
let backgroundview1: UIView =
{
let view = UIView()
view.backgroundColor = .purple
return view
}()
let edittasktextview1: UITextView = {
let tv = UITextView()
tv.backgroundColor = .black
return tv
}()
let cancelButton : UIButton = {
let button = UIButton(type: .system)
button.setTitle("Cancel", for: .normal)
button.addTarget(self, action: #selector(handleCancelButton), for:
.touchUpInside)
return button
}()
let doneButton1 : UIButton = {
let button = UIButton(type: .system)
button.setTitle("Done", for: .normal)
button.addTarget(self, action: #selector(handleDoneButton), for: .touchUpInside)
return button
}()
#objc func handleCancelButton() {
edittasktextview1.endEditing(true)
dismiss(animated: true, completion: nil)
}
#objc func handleDoneButton()
{
dismiss(animated: true, completion: nil)
if edittasktextview1.text.isEmpty == true
{
moContext.delete(editnotes!)
}
else
{
editnotes?.sNote = edittasktextview1.text
}
var error: NSError?
do {
// Save The object
try moContext.save()
print("SAVED")
} catch let error1 as NSError {
error = error1
}
edittasktextview1.endEditing(true)
}
override func viewWillDisappear(_ animated: Bool) {
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "NotificationID"), object: nil)
}
override func viewDidAppear(_ animated: Bool) {
//add something here
// edittasktextview.becomeFirstResponder()
}
override func viewDidLoad() {
super.viewDidLoad()
self.navigationController?.navigationBar.tintColor = UIColor.white
navigationItem.title = "Edit Tasks"
edittasktextview1.text = editnotes?.sNote
backgroundview1.backgroundColor = editnotes?.sPriorityColor
edittasktextview1.backgroundColor = .clear
setupviews()
//adding gesture to the background view to dismiss keyboard
let dismisskeyboardgesture = UITapGestureRecognizer()
dismisskeyboardgesture.addTarget(self, action: #selector(dismisskeyboard))
let maskPath = UIBezierPath.init(roundedRect: self.backgroundview1.bounds, byRoundingCorners:[.topLeft, .topRight], cornerRadii: CGSize.init(width: 20.0, height: 0))
let maskLayer = CAShapeLayer()
maskLayer.frame = self.backgroundview1.bounds
maskLayer.path = maskPath.cgPath
self.backgroundview1.layer.mask = maskLayer
view.backgroundColor = .clear
//view.addGestureRecognizer(dismisskeyboardgesture)
view.addSubview(mainbackgroundview)
mainbackgroundview.addSubview(backgroundview1)
// view.addSubview(backgroundview1)
backgroundview1.addSubview(edittasktextview1)
backgroundview1.addSubview(cancelButton)
backgroundview1.addSubview(doneButton1)
}
#objc func dismisskeyboard()
{
edittasktextview1.endEditing(true)
}
func setupviews()
{
mainbackgroundview.anchorToTop(view.topAnchor, left: view.leftAnchor, bottom: view.bottomAnchor, right: view.rightAnchor)
backgroundview1.anchor(view.topAnchor, left: view.leftAnchor, bottom: view.bottomAnchor, right: view.rightAnchor, topConstant: 45, leftConstant: 0, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 0)
edittasktextview1.anchor(view.topAnchor, left: view.leftAnchor, bottom: nil, right: view.rightAnchor, topConstant: 40, leftConstant: 8, bottomConstant: 0, rightConstant: 8, widthConstant: 0, heightConstant: 150)
cancelButton.anchor(edittasktextview1.bottomAnchor, left: nil, bottom: nil, right: view.rightAnchor, topConstant: 18, leftConstant: 0, bottomConstant: 0, rightConstant: 8, widthConstant: 40, heightConstant: 30)
doneButton1.anchor(edittasktextview1.bottomAnchor, left: view.leftAnchor, bottom: nil, right: nil, topConstant: 18, leftConstant: 8, bottomConstant: 0, rightConstant: 0, widthConstant: 40, heightConstant: 30)
}
}
Help will be appreciated, as I am stuck at this problem for nearly 18 hours :(
UPDATE #1
Not getting the same error now, however, I am not able to set the backgroundview1 on the mainbackgroundview.
I am adding it as a subview:
mainbackgroundview.addSubview(backgroundview1)
In setupviews() I am placing the constraint like so:
NSLayoutConstraint.activate([
backgroundview1.leftAnchor.constraint(equalTo: mainbackgroundview.leftAnchor, constant: 0),
backgroundview1.rightAnchor.constraint(equalTo: mainbackgroundview.rightAnchor, constant: 0),
backgroundview1.bottomAnchor.constraint(equalTo: mainbackgroundview.bottomAnchor, constant: 0),
backgroundview1.topAnchor.constraint(equalTo: mainbackgroundview.topAnchor, constant: 45)
])
Still I am not getting the backgroundview1 to be placed on the mainbackgroundview. The mainbackgroundview is showing up though on the simulator.
I am adding mainbackgroundview like so:
NSLayoutConstraint.activate([
mainbackgroundview.leftAnchor.constraint(equalTo: view.leftAnchor),
mainbackgroundview.rightAnchor.constraint(equalTo: view.rightAnchor),
mainbackgroundview.topAnchor.constraint(equalTo: view.topAnchor),
mainbackgroundview.bottomAnchor.constraint(equalTo: view.bottomAnchor)
])
What am I doing wrong now?

Answer 1

In setupViews() function you are adding constraints but not setting them as active. This is a sample anchor constraint that can be added successfully:
myView.bottomAnchor.constraint(equalTo: view.topAnchor,
constant: 8).isActive=true
Try adding .isActive at the end of each of your constraint.
Moreover you can add relevant anchor constraints for example: topAnchor, bottomAnchor, widthAnchor, heightAnchor, leadingAnchor etc. Try simplifying your constraints.