Remove views in UIstackview swift

Question

I am new to swift. I have added view to stackview using addArrangedSubview(). But I am not able to remove this view using removeArrangedSubview(). Even after removing arranged subView the view is still present

import Foundation
import UIKit

class render: UIViewController {

  let subview    = UIStackView()
  let mainview   = UIStackView()

  override func viewDidLoad() {
    super.viewDidLoad()

    self.mainviewlet()
    self.login()
  }

  func login() {

    let username = UITextField()
    // text field

    let button = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 40))
    //button

    // Adding to subview  
    subview.axis  = UILayoutConstraintAxis.vertical
    subview.distribution  = UIStackViewDistribution.equalSpacing
    subview.alignment = UIStackViewAlignment.center
    subview.spacing   = 16.0

    subview.addArrangedSubview(username)
    subview.addArrangedSubview(button)

    subview.translatesAutoresizingMaskIntoConstraints = false;

    // Adding subview to another stackview
    mainview.addArrangedSubview(subview)
    self.view.addSubview(mainview)

}

In another function I am removing the arranged subview

func signup(sender: UIButton!) {

    // Remove subview
    mainview.removeArrangedSubview(subview)
    subview.removeFromSuperview()

    let firstname = UITextField()
    firstname.textAlignment = NSTextAlignment.center
    firstname.textColor = UIColor.black
    firstname.frame = CGRect()
    firstname.frame.size.height = 30;
    firstname.text = "firstname"

    subview.addArrangedSubview(firstname)
    mainview.addArrangedSubview(subview)
    self.view.addSubview(mainview)
}

and my mainview is created as:

func mainviewlet {

  mainview.axis  = UILayoutConstraintAxis.vertical
  mainview.distribution  = UIStackViewDistribution.equalSpacing
  mainview.alignment = UIStackViewAlignment.center
  mainview.spacing   = 16.0
  mainview.translatesAutoresizingMaskIntoConstraints = false;

  self.view.addSubview(mainview)
}

I want the username & button to be deleted and add new field firstname to the subview.

Am I doing it the right way ? How to delete subview ? Thanks for any help

Answer 1

In Swift 5.4

removeArrangedSubview method removes the provided view from the stack’s arrangedSubviews array. The view’s position and size will no longer be managed by the stack view. However, this method does not remove the provided view from the stack’s subviews array; therefore, the view is still displayed as part of the view hierarchy.

To prevent the view from appearing on screen after calling the stack’s removeArrangedSubview: method, explicitly remove the view from the subviews array by calling the view’s removeFromSuperview() method, or set the view’s isHidden property to true.

So:

myStackView.removeArrangedSubview(myView)
myView.removeFromSuperview()

Extended If you have a series of arranged subview, and you want to clean them, You can also create an extension:

extension UIStackView {
    
    func removeFully(view: UIView) {
        removeArrangedSubview(view)
        view.removeFromSuperview()
    }
    
    func removeFullyAllArrangedSubviews() {
        arrangedSubviews.forEach { (view) in
            removeFully(view: view)
        }
    }
    
}