removing subview (uiview) in viewcontroller from collectionview - ios

Question

How do I remove a uiview that is added into a viewcontroller whenever the user clicks on one of the collectionview? My collectionview is located inside of its own viewcontroller when the user clicks one of the collectionviewcell it will dismiss the controller (it's working) and then it will remove the contextTxt within the mainviewcontroller It did dismiss the view but it failed to remove the contextTxt and replacing it with a new view. In other words, the collectionviewcell did not trigger the #objc func inside the mainviewcontroller. Why won't it trigger?? and how do resolve this problem? Here is the code
class mainViewController: UIViewController {
let navbar:navbarView = {
let content = navbarView()
return content
}()
let contentTxt:UITextView = {
let content = UITextView()
content.backgroundColor = UIColor.green
return content
}()
let bottomBtn:UIButton = {
let content = UIButton()
content.backgroundColor = UIColor.red
return content
}()
override func viewDidLoad() {
super.viewDidLoad()
navbar.translatesAutoresizingMaskIntoConstraints = false
contentTxt.translatesAutoresizingMaskIntoConstraints = false
bottomBtn.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(navbar)
view.addSubview(contentTxt)
contentTxt.addSubview(bottomBtn)
navbar.topAnchor.constraint(
equalTo: view.topAnchor, constant: 20).isActive = true
navbar.centerXAnchor.constraint(
equalTo: view.centerXAnchor).isActive = true
navbar.widthAnchor.constraint(
equalTo: view.widthAnchor).isActive = true
navbar.heightAnchor.constraint(
equalToConstant: 50).isActive = true
contentTxt.topAnchor.constraint(
equalTo: navbar.bottomAnchor, constant: 5).isActive = true
contentTxt.centerXAnchor.constraint(
equalTo: view.centerXAnchor).isActive = true
contentTxt.widthAnchor.constraint(
equalTo: view.widthAnchor).isActive = true
contentTxt.bottomAnchor.constraint(
equalTo: view.bottomAnchor, constant: 0).isActive = true
bottomBtn.bottomAnchor.constraint(
equalTo: contentTxt.bottomAnchor).isActive = true
bottomBtn.centerXAnchor.constraint(
equalTo: contentTxt.centerXAnchor).isActive = true
bottomBtn.widthAnchor.constraint(
equalToConstant: 40).isActive = true
bottomBtn.heightAnchor.constraint(
equalToConstant: 40).isActive = true
}
#objc func addConnections(){
self.contentTxt.removeFromSuperview()
let connect:connectView = {
let content = connectView()
content.backgroundColor = UIColor.red
return content
}()
connect.translatesAutoresizingMaskIntoConstraints = false
self.view.addSubview(connect)
connect.topAnchor.constraint(
equalTo: navbar.bottomAnchor, constant: 5).isActive = true
connect.centerXAnchor.constraint(
equalTo: view.centerXAnchor).isActive = true
connect.widthAnchor.constraint(
equalTo: view.widthAnchor).isActive = true
connect.bottomAnchor.constraint(
equalTo: view.bottomAnchor, constant: 0).isActive = true
}
#objc func sideController(){
let next = self.storyboard?.instantiateViewController(
withIdentifier: "sideViewController") as! sideViewController
self.present(next, animated: true, completion: nil)
}
#objc func profileController(){
let next = self.storyboard?.instantiateViewController(
withIdentifier: "profileViewController") as! profileViewController
self.present(next, animated: true, completion: nil)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Here is the collectionview code:
class sideCollectionView:UIView, UICollectionViewDelegateFlowLayout,UICollectionViewDataSource {
var currentVc:sideViewController?
var mainVc=mainViewController()
let arrayLbl = ["connection","achievement","template","setting"]
let arrayImg = ["connection","achievement","template","setting"]
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return arrayLbl.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! sideCollectionViewCell
cell.titleImg.image = UIImage(named: "\(arrayImg[indexPath.row])")
cell.titleLbl.text = arrayLbl[indexPath.row]
return cell
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: (self.frame.width / 2) - 40, height: (self.frame.width / 2) - 40)
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
return UIEdgeInsetsMake(25, 25, 10, 25)
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
if indexPath.row == 0{
print("connection")
currentVc?.bye()
mainVc.addConnections()
}
if indexPath.row == 1{
print("achievement")
currentVc?.bye()
}
if indexPath.row == 2{
print("template")
currentVc?.bye()
}
if indexPath.row == 3{
print("setting")
currentVc?.bye()
}
}
lazy var collectionViews: UICollectionView = {
let layout = UICollectionViewFlowLayout()
let cv = UICollectionView(frame: .zero, collectionViewLayout: layout)
cv.backgroundColor = UIColor.clear
cv.dataSource = self
cv.delegate = self
return cv
}()
override init(frame: CGRect) {
super.init(frame: frame)
setupViews()
}
func setupViews(){
collectionViews.register(sideCollectionViewCell.self, forCellWithReuseIdentifier: "cell")
collectionViews.translatesAutoresizingMaskIntoConstraints = false
backgroundColor = UIColor.clear
addSubview(collectionViews)
collectionViews.topAnchor.constraint(equalTo: topAnchor, constant: 0).isActive = true
collectionViews.bottomAnchor.constraint(equalTo: bottomAnchor, constant: 0).isActive = true
collectionViews.centerYAnchor.constraint(equalTo: centerYAnchor, constant: 0).isActive = true
collectionViews.centerXAnchor.constraint(equalTo: centerXAnchor, constant: 0).isActive = true
collectionViews.widthAnchor.constraint(equalTo: widthAnchor, constant: 0).isActive = true
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}

Answer 1

Because var mainVc=mainViewController() creates a new mainViewController which is not the existing mainViewController.
You can try getting the parent mainViewController by this way.
var mainVc: mainViewController? {
return currentVc?.presentingViewController as? mainViewController
}

Answer 2

When presenting sideViewController, set the mainVc variable to self so that it is pointing to the actual mainVc object:
#objc func sideController(){
let next = self.storyboard?.instantiateViewController(withIdentifier: "sideViewController") as! sideViewController
next.mainVc = self
self.present(next, animated: true, completion: nil)
}