[iOS] Custom back button with back gesture



When I want to change the default iOS back button, I need to hide the default back button. This causes the back gesture is also disabled. Therefore, I need to keep the back gesture and make the change.

To make these happen, I do steps:
  1. Disable the default back button
  2. Set the new back button to left bar item
  3. Enable the navigation interaction gesture for back gesture
Here is the codes (Swift 5)
class MyViewController: UIGestureRecognizerDelegate {
  self.navigationItem.hidesBackButton = true

  let image = UIImage(systemName: "chevron.backward")
  let backBarItem = UIBarButtonItem(image: image, style: .plain, target: nil, action: nil)
  self.navigationItem.leftBarButtonItem = backBarItem

  self.navigationController?.interactivePopGestureRecognizer?.delegate = self
  
  func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldBeRequiredToFailBy otherGestureRecognizer: UIGestureRecognizer) -> Bool {
     return true
  }
}

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