411 lines
19 KiB
Swift
411 lines
19 KiB
Swift
//
|
|
// AccessibilityHandler.swift
|
|
// MVMCoreUI
|
|
//
|
|
// Created by Bandaru, Krishna Kishore on 30/06/23.
|
|
// Copyright © 2023 Verizon Wireless. All rights reserved.
|
|
//
|
|
|
|
import Foundation
|
|
import Combine
|
|
import MVMCore
|
|
import WebKit
|
|
|
|
public class AccessbilityOperation: MVMCoreOperation {
|
|
|
|
private let argument: Any?
|
|
private let notificationType: UIAccessibility.Notification
|
|
private var timerSource: DispatchSourceTimer?
|
|
|
|
public init(notificationType: UIAccessibility.Notification, argument: Any?) {
|
|
self.notificationType = notificationType
|
|
self.argument = argument
|
|
}
|
|
|
|
public override func main() {
|
|
guard UIAccessibility.isVoiceOverRunning, !checkAndHandleForCancellation() else {
|
|
stop()
|
|
return
|
|
}
|
|
timerSource = DispatchSource.makeTimerSource()
|
|
timerSource?.setEventHandler {
|
|
Task { @MainActor [weak self] in
|
|
guard let self = self, !self.isCancelled else {
|
|
self?.stop()
|
|
return
|
|
}
|
|
UIAccessibility.post(notification: self.notificationType, argument: self.argument)
|
|
self.markAsFinished()
|
|
}
|
|
}
|
|
timerSource?.schedule(deadline: .now())
|
|
timerSource?.activate()
|
|
}
|
|
|
|
public func stop() {
|
|
guard isCancelled else { return }
|
|
timerSource?.cancel()
|
|
markAsFinished()
|
|
}
|
|
}
|
|
|
|
open class AccessibilityHandler {
|
|
|
|
public static func shared() -> Self? {
|
|
guard let shared = CoreUIObject.sharedInstance()?.accessibilityHandler else { return nil }
|
|
return MVMCoreActionUtility.fatalClassCheck(object: shared)
|
|
}
|
|
|
|
public var previousAccessiblityElement: Any?
|
|
public var anyCancellable: Set<AnyCancellable> = []
|
|
public weak var delegate: MVMCoreViewControllerProtocol?
|
|
|
|
private var accessibilityOperationQueue: OperationQueue = {
|
|
let queue = OperationQueue()
|
|
queue.maxConcurrentOperationCount = 1
|
|
return queue
|
|
}()
|
|
private(set) var accessibilityId: String?
|
|
private var announcementText: String?
|
|
private(set) var hasTopNotitificationInPage: Bool = false
|
|
|
|
public init() {
|
|
registerWithResponseLoaded()
|
|
registerForPageChanges()
|
|
registerForFocusChanges()
|
|
}
|
|
|
|
// MARK: - Register with Accessibility Handler listeners
|
|
/// Registers with the notification center to know when json is updated and to capture previous accessbility focused id & announcment text
|
|
private func registerWithResponseLoaded() {
|
|
NotificationCenter.default.publisher(for: NSNotification.Name(rawValue: NotificationResponseLoaded))
|
|
.sink { [weak self] notification in
|
|
self?.accessibilityId = (notification.userInfo?[String(describing: MVMCoreLoadObject.self)] as? MVMCoreLoadObject)?.pageJSON?.optionalStringForKey("accessibilityId")
|
|
self?.announcementText = (notification.userInfo?[String(describing: MVMCoreLoadObject.self)] as? MVMCoreLoadObject)?.pageJSON?.optionalStringForKey("announcementText")
|
|
}.store(in: &anyCancellable)
|
|
}
|
|
|
|
private func registerForFocusChanges() {
|
|
//Since foucs shifted to other elements cancelling existing focus shift notifications if any
|
|
NotificationCenter.default.publisher(for: UIAccessibility.elementFocusedNotification)
|
|
.sink { [weak self] _ in
|
|
self?.cancelAllOperations()
|
|
}.store(in: &anyCancellable)
|
|
}
|
|
|
|
func registerForTopNotificationsChanges() {
|
|
NotificationHandler.shared()?.onNotificationWillShow
|
|
.sink { [weak self] (_, model) in
|
|
self?.hasTopNotitificationInPage = true
|
|
self?.capturePreviousFocusElement()
|
|
}.store(in: &anyCancellable)
|
|
NotificationHandler.shared()?.onNotificationShown
|
|
.sink { [weak self] (view, model) in
|
|
self?.post(notification: .layoutChanged, argument: view)
|
|
}.store(in: &anyCancellable)
|
|
NotificationHandler.shared()?.onNotificationWillDismiss
|
|
.sink { [weak self] (view, model) in
|
|
self?.post(notification: .announcement, argument: MVMCoreUIUtility.hardcodedString(withKey: "AccTopAlertClosed"))
|
|
}.store(in: &anyCancellable)
|
|
NotificationHandler.shared()?.onNotificationDismissed
|
|
.sink { [weak self] (view, model) in
|
|
self?.postAccessbilityToPrevElement()
|
|
}.store(in: &anyCancellable)
|
|
}
|
|
|
|
/// Registers to know when pages change.
|
|
open func registerForPageChanges() {
|
|
NavigationHandler.shared()
|
|
.onNavigation
|
|
.sink { [self] (event, operation) in
|
|
switch event {
|
|
case .willNavigate:
|
|
willNavigate(operation)
|
|
default:
|
|
break
|
|
}
|
|
}.store(in: &anyCancellable)
|
|
}
|
|
|
|
private func willNavigate(_ operation: NavigationOperation) {
|
|
previousAccessiblityElement = nil
|
|
if let announcementText {
|
|
post(notification: .announcement, argument: announcementText)
|
|
}
|
|
if let subNavManagerController = operation.toNavigationControllerViewControllers?.last as? SubNavManagerController {
|
|
delegate = subNavManagerController.getCurrentViewController() as? MVMCoreViewControllerProtocol
|
|
} else {
|
|
delegate = operation.toNavigationControllerViewControllers?.last as? MVMCoreViewControllerProtocol
|
|
}
|
|
}
|
|
|
|
// MARK: - Accessibility Handler operation events
|
|
open func capturePreviousFocusElement() {
|
|
previousAccessiblityElement = UIAccessibility.focusedElement(using: .notificationVoiceOver)
|
|
}
|
|
|
|
open func postAccessbilityToPrevElement() {
|
|
post(notification: .layoutChanged, argument: previousAccessiblityElement)
|
|
}
|
|
|
|
private func add(operation: Operation) {
|
|
accessibilityOperationQueue.addOperation(operation)
|
|
}
|
|
|
|
private func cancelAllOperations() {
|
|
accessibilityOperationQueue.cancelAllOperations()
|
|
}
|
|
|
|
public func post(notification type: UIAccessibility.Notification, argument: Any? = nil) {
|
|
guard UIAccessibility.isVoiceOverRunning else { return }
|
|
let accessbilityOperation = AccessbilityOperation(notificationType: type, argument: argument)
|
|
add(operation: accessbilityOperation)
|
|
}
|
|
|
|
//To get first focus element on the screen
|
|
open func getFirstFocusedElementOnScreen() -> Any? {
|
|
(delegate as? UIViewController)?.navigationItem.leftBarButtonItem ?? (delegate as? UIViewController)?.navigationItem.titleView ?? (delegate as? UIViewController)?.navigationController?.navigationBar
|
|
}
|
|
|
|
//Subclass can decide to trigger Accessibility notification on screen change.
|
|
open func canPostAccessbilityNotification(for viewController: UIViewController) -> Bool { true }
|
|
|
|
func getPreDefinedFocusedElementIfAny() -> UIView? {
|
|
guard let accessibilityId else { return nil }
|
|
var modelElement: MoleculeModelProtocol?
|
|
((delegate?.delegateObject?() as? MVMCoreUIDelegateObject)?.moleculeDelegate)?.getRootMolecules().depthFirstTraverse(options: .leafNodesOnly, depth: 0) { index, model, stop in
|
|
if model.id == accessibilityId {
|
|
modelElement = model
|
|
stop = true
|
|
}
|
|
}
|
|
return (delegate as? UIViewController)?.view?.getMoleculeViews { (subView: MoleculeViewProtocol, stop: inout Bool) in
|
|
guard let modelElement, let moleculeModel = (subView as? MoleculeViewModelProtocol)?.moleculeModel,
|
|
moleculeModel.id == modelElement.id else {
|
|
return false
|
|
}
|
|
stop = true
|
|
return true
|
|
}.first
|
|
}
|
|
}
|
|
|
|
// MARK: - Accessibility Handler Behaviour
|
|
///Accessibility Handler Behaviour to detect page shown and post notification to first interactive element on screen or the pre-defined focused element.
|
|
open class AccessibilityHandlerBehavior: PageVisibilityBehavior {
|
|
|
|
enum RotorType: String, CaseIterable {
|
|
|
|
case button = "Buttons"
|
|
case header = "Header"
|
|
|
|
var trait: UIAccessibilityTraits {
|
|
switch self {
|
|
case .button:
|
|
return .button
|
|
case .header:
|
|
return .header
|
|
}
|
|
}
|
|
|
|
func getUIAccessibilityCustomRotor(itemSearch: @escaping UIAccessibilityCustomRotor.Search) -> UIAccessibilityCustomRotor? {
|
|
var accessibilityCustomRotor: UIAccessibilityCustomRotor?
|
|
switch self {
|
|
case .header:
|
|
accessibilityCustomRotor = UIAccessibilityCustomRotor(systemType: .heading, itemSearch: itemSearch)
|
|
default:
|
|
accessibilityCustomRotor = UIAccessibilityCustomRotor(name: rawValue, itemSearch: itemSearch)
|
|
}
|
|
return accessibilityCustomRotor
|
|
}
|
|
}
|
|
|
|
public var anyCancellable: Set<AnyCancellable> = []
|
|
private var delegateObj: MVMCoreUIDelegateObject?
|
|
private var rotorIndexes: [RotorType: Int] = [:]
|
|
|
|
required public init(model: PageBehaviorModelProtocol, delegateObject: MVMCoreUIDelegateObject?) { }
|
|
|
|
//MARK: - PageVisibiltyBehaviour
|
|
open func willShowPage(_ delegateObject: MVMCoreUIDelegateObject?) {
|
|
updateAccessibilityViews(delegateObject)
|
|
guard let controller = delegateObject?.moleculeDelegate as? UIViewController,
|
|
(AccessibilityHandler.shared()?.canPostAccessbilityNotification(for: controller) ?? true),
|
|
AccessibilityHandler.shared()?.accessibilityId == nil else { return }
|
|
if AccessibilityHandler.shared()?.hasTopNotitificationInPage ?? false {
|
|
AccessibilityHandler.shared()?.previousAccessiblityElement = AccessibilityHandler.shared()?.getFirstFocusedElementOnScreen()
|
|
} else {
|
|
AccessibilityHandler.shared()?.post(notification: .layoutChanged, argument: AccessibilityHandler.shared()?.getFirstFocusedElementOnScreen())
|
|
}
|
|
delegateObj = delegateObject
|
|
}
|
|
|
|
///We need to shift focus to any element mentioned in server response i.e to retain focus of the element in new page, from where action is triggered.
|
|
///https://oneconfluence.verizon.com/display/MFD/Accessibility+-+Focus+Retain
|
|
open func onPageShown(_ delegateObject: MVMCoreUIDelegateObject?) {
|
|
updateAccessibilityViews(delegateObject) //To track FAB & HAB elements on UI
|
|
identifyAndPrepareRotors()
|
|
guard let accessibilityElement = AccessibilityHandler.shared()?.getPreDefinedFocusedElementIfAny() else { return }
|
|
if AccessibilityHandler.shared()?.hasTopNotitificationInPage ?? false {
|
|
AccessibilityHandler.shared()?.previousAccessiblityElement = accessibilityElement
|
|
} else {
|
|
AccessibilityHandler.shared()?.post(notification: .layoutChanged, argument: accessibilityElement)
|
|
}
|
|
}
|
|
|
|
//MARK: - Accessibility Methods
|
|
|
|
private func updateAccessibilityViews(_ delegateObject: MVMCoreUIDelegateObject?) {
|
|
var accessibilityElements: [Any?] = [MVMCoreUISplitViewController.main()?.topAlertView]
|
|
if let managerController = (delegateObject?.moleculeDelegate as? MVMCoreViewManagerViewControllerProtocol)?.manager as? SubNavManagerController {
|
|
accessibilityElements.append(managerController.navigationController)
|
|
accessibilityElements.append(managerController.tabs)
|
|
accessibilityElements.append(contentsOf: managerController.view.subviews)
|
|
accessibilityElements.append(MVMCoreUISplitViewController.main()?.tabBar)
|
|
managerController.view.accessibilityElements = accessibilityElements.compactMap { $0 }
|
|
} else if let controller = delegateObject?.moleculeDelegate as? UIViewController {
|
|
accessibilityElements.append(controller.navigationController)
|
|
accessibilityElements.append(contentsOf: controller.view.subviews.reversed())
|
|
accessibilityElements.append(MVMCoreUISplitViewController.main()?.tabBar)
|
|
controller.view.accessibilityElements = accessibilityElements.compactMap { $0 }
|
|
}
|
|
}
|
|
|
|
//MARK: - Rotor Methods
|
|
private func identifyAndPrepareRotors() {
|
|
var rotorElements: [UIAccessibilityCustomRotor] = []
|
|
let currentViewController = ((delegateObj?.moleculeDelegate as? MVMCoreViewManagerViewControllerProtocol)?.manager as? SubNavManagerController) ?? (delegateObj?.moleculeDelegate as? ViewController)
|
|
for type in RotorType.allCases {
|
|
if let elements = getTraitMappedElements(currentViewController, type: type),
|
|
let rotor = createRotor(elements, for: type) {
|
|
rotorElements.append(rotor)
|
|
}
|
|
}
|
|
currentViewController?.navigationController?.accessibilityCustomRotors = rotorElements
|
|
}
|
|
|
|
private func getTraitMappedElements(_ template: ViewController?, type: RotorType) -> [Any]? {
|
|
var accessibilityElements: [Any?] = []
|
|
switch type {
|
|
case .button:
|
|
accessibilityElements.append(contentsOf: template?.navigationItem.leftBarButtonItems ?? [])
|
|
accessibilityElements.append(contentsOf: template?.navigationItem.rightBarButtonItems ?? [])
|
|
case .header:
|
|
accessibilityElements.append(template?.navigationItem.titleView)
|
|
}
|
|
if let tabs = (template as? SubNavManagerController)?.tabs {
|
|
accessibilityElements.append(contentsOf: tabs.subviews.filter {
|
|
$0.accessibilityTraits.contains(type.trait)
|
|
})
|
|
}
|
|
if let rotorElements = getRotorElementsFrom(template: template, type: type) {
|
|
accessibilityElements.append(contentsOf: rotorElements)
|
|
}
|
|
if let tabBarHidden = (template as? TabPageModelProtocol)?.tabBarHidden, !tabBarHidden {
|
|
accessibilityElements.append(contentsOf: (MVMCoreUISplitViewController.main()?.tabBar?.subviews ?? []).filter {
|
|
$0.accessibilityTraits.contains(type.trait)
|
|
})
|
|
}
|
|
return accessibilityElements.compactMap { $0 }
|
|
}
|
|
|
|
private func getRotorElementsFrom(template: ViewController?, type: RotorType) -> [Any]? {
|
|
if let currentViewController = template as? MoleculeListTemplate,
|
|
let templateModel = currentViewController.templateModel,
|
|
let tableView = currentViewController.tableView { //List templates
|
|
var rotorElements: [(model: MoleculeModelProtocol, indexPath: IndexPath)] = []
|
|
var currentIndexPath: IndexPath?
|
|
|
|
rotorElements = templateModel.reduceDepthFirstTraverse(options: .parentFirst, depth: 0, initialResult: rotorElements, nextPartialResult: { result, model, depth in
|
|
if let listModel = model as? (ListItemModelProtocol & MoleculeModelProtocol), let indexPath = currentViewController.getIndexPath(for: listModel) {
|
|
currentIndexPath = indexPath
|
|
}
|
|
var result = result
|
|
if (model.accessibilityTraits?.contains(type.trait) ?? false), let currentIndexPath {
|
|
result.append((model, currentIndexPath))
|
|
}
|
|
return result
|
|
})
|
|
|
|
let headerViewElements = currentViewController.tableView.tableHeaderView?.getMoleculeViews { (subView: MoleculeViewProtocol, _) in
|
|
subView.accessibilityTraits.contains(type.trait)
|
|
} as? [Any] ?? []
|
|
|
|
let footerViewElements = currentViewController.tableView.tableFooterView?.getMoleculeViews { (subView: MoleculeViewProtocol, _) in
|
|
subView.accessibilityTraits.contains(type.trait)
|
|
} as? [Any] ?? []
|
|
|
|
let otherInteractiveElements = currentViewController.view?.getMoleculeViews(excludedViews: [tableView, tableView.tableFooterView, tableView.tableHeaderView]
|
|
.compactMap { $0 }) { (subView: MoleculeViewProtocol, _) in
|
|
subView.accessibilityTraits.contains(type.trait)
|
|
} as? [Any] ?? []
|
|
|
|
return headerViewElements + otherInteractiveElements + (rotorElements as [Any]) + footerViewElements
|
|
} else if let currentViewController = template as? MoleculeStackTemplate { //Stack templates
|
|
return currentViewController.view?.getMoleculeViews { (subView: MoleculeViewProtocol, _) in
|
|
subView.accessibilityTraits.contains(type.trait)
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
private func createRotor(_ elements: [Any], for type: RotorType) -> UIAccessibilityCustomRotor? {
|
|
guard !elements.isEmpty else { return nil }
|
|
return type.getUIAccessibilityCustomRotor { [weak self] predicate in
|
|
guard let self else { return UIAccessibilityCustomRotorItemResult() }
|
|
var rotorIndex = self.rotorIndexes[type] ?? 0
|
|
if predicate.searchDirection == .next {
|
|
rotorIndex += 1
|
|
if rotorIndex > elements.count {
|
|
rotorIndex = 1
|
|
}
|
|
} else {
|
|
rotorIndex -= 1
|
|
if rotorIndex <= 0 {
|
|
rotorIndex = elements.count
|
|
}
|
|
}
|
|
var rotorElement = elements[rotorIndex - 1]
|
|
if let tableView = (self.delegateObj?.moleculeListDelegate as? MoleculeListTemplate)?.tableView,
|
|
let element = rotorElement as? (model: MoleculeModelProtocol, indexPath: IndexPath) { //for List templates
|
|
tableView.scrollToRow(at: element.indexPath, at: .middle, animated: false)
|
|
rotorElement = tableView.cellForRow(at: element.indexPath)?.getMoleculeViews { (subView: MoleculeViewProtocol, stop: inout Bool) in
|
|
guard subView.accessibilityTraits.contains(type.trait), (subView as? MoleculeViewModelProtocol)?.moleculeModel?.id == element.model.id else { return false }
|
|
stop = true
|
|
return true
|
|
}.first as Any
|
|
}
|
|
self.rotorIndexes[type] = rotorIndex
|
|
AccessibilityHandler.shared()?.post(notification: .layoutChanged, argument: rotorElement)
|
|
return UIAccessibilityCustomRotorItemResult(targetElement: rotorElement as! NSObjectProtocol, targetRange: nil)
|
|
}
|
|
}
|
|
}
|
|
|
|
// MARK: - Helpers
|
|
extension UIView {
|
|
|
|
private func getNestedSubviews<T>(excludedViews: [UIView]? = nil) -> [T] {
|
|
subviews.flatMap { subView -> [T] in
|
|
guard !(excludedViews?.contains(subView) ?? false) else { return [] }
|
|
var result = subView.getNestedSubviews() as [T]
|
|
if let view = subView as? T { result.append(view) }
|
|
return result
|
|
}
|
|
}
|
|
|
|
func getMoleculeViews<T>(excludedViews: [UIView]? = nil, filter: ((T, inout Bool) -> Bool)) -> [T] {
|
|
var stop = false
|
|
var results: [T] = []
|
|
for element: T in getNestedSubviews(excludedViews: excludedViews) {
|
|
if filter(element, &stop) {
|
|
results.append(element)
|
|
}
|
|
if stop {
|
|
break
|
|
}
|
|
}
|
|
return results
|
|
}
|
|
}
|