Customising accessibility in recyclerview using onPopulateAccessibilityEvent and AccessibilityDelegate

问题

I'm trying to customise the talkback output for items in a RecyclerView. I have modified the onBindViewHolder method to include the following code

       itemView?.setAccessibilityDelegate(object: View.AccessibilityDelegate() {
            override fun onPopulateAccessibilityEvent(host: View?, event: AccessibilityEvent?) {
                super.onPopulateAccessibilityEvent(host, event)
                event?.let {event ->
                    if (event.eventType == AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED) {
                        event.text.add("Hello world!")
                    }
                }
            }
        })

Unfortunately, the talkback output is only modified for the last visible item in the RecyclerView.

I don't understand why the delegate works for some ViewHolders and not others.

回答1:

RecyclerView adds AccessibilityDelegates to its children to add its own actions to them. Since a View may have at most one delegate, whichever one is added first (yours or the one for RecyclerView) gets clobbered.

RecyclerView has its own wrapper of AccessibilityDelegate that works for its children. That's what you want.

来源：https://stackoverflow.com/questions/48446769/customising-accessibility-in-recyclerview-using-onpopulateaccessibilityevent-and