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iOS accessibility issue - focus goes to a random position

Recently, I faced an issue where the Accessibility(ADD) control goes to random position after selecting a table section/row. On one screen where I worked, there was requirement of collapsing and expanding table header. When user tried to collapse/expand the header, the ADD control goes to random position. 
Initially, I tried to post the accessibility notification to set the ADD control to specific section, but it didn't work. (Generally, In most of the cases it works)
UIAccessibility.post(notification: .layoutChanged, argument: sectionInstance)
Secondly, I tried to use the below method. By using this method, I get a callback when an element has ADD focus. When I get a callback, I scrolled the table to the desired position and then post notification, but sadly it didn't work too.
override func accessibilityElementDidBecomeFocused()
Finally, I used the default scroll method (scrollViewDidScroll) where I got the regular callbacks when table scrolls. When a section is collapsed/expanded, then a particular section reloads which gives me a callback on scroll delegate method. Also, I keep the variable that keeps track of which section is reloaded/selected. Now, after getting callback in scroll method, I scrolled the table to selected section, then post the above accessibility notification. As reload operation takes mini seconds to complete, I use the delay of two miliseconds to do this operation.
func scrollViewDidScroll(_ scrollView: UIScrollView) 
Now, it's not all perfect. It seems that on collapsing the header, the selected header is not visible (generally happens on smaller devices) and accessibility control goes to random position in this edge case. To help that problem, in above scroll method, check the visible index paths. If the selected section/index path is not visible, then first scroll the tableview to selected section and post the ADD notification on completion.
Note: Below is an article that addresses some issues with scrolling and custom tableViews. Whenever a custom cell gets scrolled, the accessibilityFrame changes so some work is required to let UIKit know what exactly to voice over. https://coderwall.com/p/sswchq/ios-custom-views-and-accessibility-in-table-views There is a fair bit of customization required, hopefully, you can look through and find a small subset that works for your use case.
Let me know if any issues and a better way.

Comments

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