Use `navigationItem.backButtonDisplayMode = .minimal` with a custom back button image - ios

Question

For an iOS 14+ app I'd like to use navigationItem.backButtonDisplayMode = .minimal to hide the back button title, while still having the title available in the back button's long-press menu. Which works.. however I also want to change the back button image, to replace the default chevron.
But no matter what I try, I can't seem to find a solution that shows a custom back button image without a title, while also not showing a blank space in the back button's long-press menu, and not breaking the slide-to-go-back-gesture.
Anyone tried something similar, and succeeded?
So in the first view controller I show a title:
And then in the pushed view controller I want to show a custom back button image WITHOUT the "one" title (as seen below), and still have the long-press menu say "one" instead of a blank space.
This mostly gets me there actually, except that it breaks the gesture to slide to go back:
override func viewDidLoad() {
super.viewDidLoad()
let backImage = UIImage(named: "backImage")?.withRenderingMode(.alwaysOriginal)
navigationController?.navigationBar.backIndicatorImage = backImage
navigationController?.navigationBar.backIndicatorTransitionMaskImage = backImage
navigationItem.backButtonDisplayMode = .minimal
}
Update: actually it only seems to break on the simulator, it's all fine on an actual device. I now have a minimal project setup where it all works, now to find out why it doesn't work in my actual big project!

Answer 1

Okay, I finally figured out all the problems I was having.
Basically, this code works just fine:
override func viewDidLoad() {
super.viewDidLoad()
let backImage = UIImage(named: "backImage")?.withRenderingMode(.alwaysOriginal)
navigationController?.navigationBar.backIndicatorImage = backImage
navigationController?.navigationBar.backIndicatorTransitionMaskImage = backImage
navigationItem.backButtonDisplayMode = .minimal
}
But I was having problems with the swipe back gesture not working anymore. Turns out, that's a simulator bug, works fine on device. Then there was the problems that the custom back button image didn't actually show up in my view, because of this:
let appearance = UINavigationBarAppearance()
appearance.backgroundColor = .pageBackground
appearance.titleTextAttributes = [.foregroundColor: UIColor.abbey]
appearance.shadowColor = .clear
navigationBar.scrollEdgeAppearance = appearance
navigationBar.standardAppearance = appearance
navigationBar.compactAppearance = appearance
As soon as you set a custom appearance, that completely wipes away the custom back button image. Simple fix, just set these things directly on the navigationBar without involving the appearance.
And now it all works!

Answer 2

To set the image, you can use:
navigationController?.navigationBar.backIndicatorImage = yourBackImage
navigationController?.navigationBar.backIndicatorTransitionMaskImage = yourBackImage
Let's say you have navigation from AVC to BVC.
If you want to disable the long press menu, you can follow this answer.
If you want the long press menu to work with the correct titles, you need to set navigationItem.title for your AVC to the right value, and navigationItem.backBarButtonItem should be nil(it's the default value) for BVC.
If you don't want to display the title in your AVC, you can hide it with titleView:
navigationItem.title = "title for long press navigation menu"
navigationItem.titleView = UIView()