Supplies a page's accessible elements that are not page content (form fields, links, comments) in keyboard focus order: the seam the viewer's annotation, link and form layers implement.
public interface IAccessibleElementProvider
ISO 32000-2 §12.5 (annotations), §12.7 (forms), Spec #33 viewer capability 8. The bridge appends the elements to the page's node after its content, in the order given, and Control walks them. When an element's value or state changes, call InvalidatePage(Int32); when the layer moves its keyboard focus, call SetFocus(AccessibleNode?) with FindNode(Int32, Object).
kind:method, kind:property, kind:ctor. Press Esc to clear.GetElements(PdfPage, Int32, ICollection<AccessibleElement>)Adds a page's elements, in focus order.