UIStackView : Is it really necessary to call both removeFromSuperView and removeArrangedSubview to remove a subview?

Question

From the UIStackView Class Reference

In removeArrangedSubview:

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.

In arrangedSubview:

Whenever an arranged view’s removeFromSuperview method is called, the stack view removes the view from its arrangedSubview array

From these, it seems that calling just removeFromSuperview is enough to remove a subview and I've been using it like that without problems. I also confirmed the behavior by logging the count of the arrangedSubviews array when removeFromSuperview is called.

A lot of tutorials and comments here on S/O however, say to call both. Is there a reason for this? Or do people just do it because the documentation says so?

Answer 1

No, just call subview.removeFromSuperview()

/* Removes a subview from the list of arranged subviews without removing it as  a subview of the receiver.     To remove the view as a subview, send it -removeFromSuperview as usual;  the relevant UIStackView will remove it from its arrangedSubviews list  automatically.  */ open func removeArrangedSubview(_ view: UIView) 

Answer 2

In iOS 12.0, You need to use

stackView.arrangedSubviews[index].removeFromSuperview() 

If you use removeArrangedSubview, there is a bug where the view at the specified index removed, but the view I want to clear appears at CGPoint(x: 0, y: 0).

Hope this help someone.