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UITextView using TextKit 1

/ 1 min read

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I received this warning and was surprised to know that there are 2 TextKits, TextKit 1 and 2 in the iOS SDK.

UITextView 0x1063c9000 is switching to TextKit 1 compatibility mode because its layoutManager was accessed. Break on void _UITextViewEnablingCompatibilityMode(UITextView *__strong, BOOL) to debug.

I use UITextView’s LayoutManager so I can detect the text or a group of texts that the user has tapped or selected.

func textViewDidChangeSelection(_ textView: UITextView) {
  textView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(textTapped(_:))))
}
@objc private func textTapped(_ sender: UITapGestureRecognizer) {
  let textView = sender.view as! CustomTextView
  let layoutManger = textView.layoutManager
  // Location of the tap
  var location = sender.location(in: textView)
  location.x -= textView.textContainerInset.left
  location.y -= textView.textContainerInset.top
  // Character index at tap location
  let characterIndex = layoutManger.characterIndex(for: location, in: textView.textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
}

So based on the answer on the question Replacing layout manager in UITextView using TextKit 1, I need to override NSLayoutManager.

class CustomTextView: UITextView {


  private var customLayoutManager = NSLayoutManager()


  init(someData: String) {
        self.someData = someData
        super.init(frame: .zero, textContainer: nil)
        customLayoutManager.textStorage = self.textStorage
        customLayoutManager.addTextContainer(self.textContainer)
        self.textContainer.replaceLayoutManager(customLayoutManager)
    }


  override var layoutManager: NSLayoutManager {
        return customLayoutManager
    }
}