There are two ways to center one UIView inside another, depending on whether you use Auto Layout or not.

If you don’t use Auto Layout, it’s only one line of code: =

Note, that sets the position once, so you need to update when for example user rotates their device.

If you’re using Auto Layout, you can center your child view inside its parent like this:

childView.centerXAnchor.constraint(equalTo: parentView.centerXAnchor).isActive = true
childView.centerYAnchor.constraint(equalTo: parentView.centerYAnchor).isActive = true

Here, our constraints will automatically update as the available space changes ☺️.