Accessibility accessibilityDecrement() not getting called

问题

Why are not accessibilityDecrement() and accessibilityIncrement() getting called in my custom UITextView when performing the appropriate gestures?

class CustomTextView: UITextView  {

   required init?(coder aDecoder: NSCoder) {
      super.init(coder: aDecoder)
      accessibilityTraits = accessibilityTraits | UIAccessibilityTraitAdjustable
   }

   override func accessibilityDecrement() {
      print("Decrement")
   }

   override func accessibilityIncrement() {
      print("Increment")
   }
}

回答1:

Try with:

isAccessibilityElement = true

accessibilityTraits = super.accessibilityTraits | UIAccessibilityTraitAdjustable

回答2:

My bad. Turns out I had forgotten that I was setting textView.accessibilityTraits = UIAccessibilityTraitStaticText in the ViewController.viewDidLoad. Duhh...

来源：https://stackoverflow.com/questions/48585236/accessibility-accessibilitydecrement-not-getting-called