Add properties for accessibilty to ASDisplayNode to support layer backed nodes

AsyncDisplayKit/ASDisplayNode.h

@@ -695,6 +695,10 @@ NS_ASSUME_NONNULL_END
 - (nullable UIView *)preferredFocusedView;
 #endif
 
+@end
+
+@interface ASDisplayNode (UIViewBridgeAccessibility)
+
 // Accessibility support
 @property (atomic, assign)           BOOL isAccessibilityElement;
 @property (nullable, atomic, copy)   NSString *accessibilityLabel;

AsyncDisplayKit/Private/ASDisplayNode+UIViewBridge.mm

@@ -709,147 +709,173 @@ if (shouldApply) { _layer.layerProperty = (layerValueExpr); } else { ASDisplayNo
   _setToLayer(edgeAntialiasingMask, edgeAntialiasingMask);
 }
 
+@end
+
+
+#pragma mark - UIViewBridgeAccessibility
+
+// ASDK supports accessibility for view or layer backed nodes. To be able to provide support for layer backed
+// nodes, properties for all of the UIAccessibility protocol defined properties need to be provided an held in sync
+// between node and view
+
+// Helper function with following logic:
+// - If the node is not loaded yet use the property from the pending state
+// - In case the node is loaded
+//  - Check if the node has a view and get the
+//  - If view is not available, e.g. the node is layer backed return the property value
+#define _getAccessibilityFromViewOrProperty(nodeProperty, viewAndPendingViewStateProperty) __loaded(self) ? \
+(_view ? _view.viewAndPendingViewStateProperty : nodeProperty )\
+: ASDisplayNodeGetPendingState(self).viewAndPendingViewStateProperty
+
+// Helper function to set property values on pending state or view and property if loaded
+#define _setAccessibilityToViewAndProperty(nodeProperty, nodeValueExpr, viewAndPendingViewStateProperty, viewAndPendingViewStateExpr) \
+nodeProperty = nodeValueExpr; _setToViewOnly(viewAndPendingViewStateProperty, viewAndPendingViewStateExpr)
+
+@implementation ASDisplayNode (UIViewBridgeAccessibility)
+
 - (BOOL)isAccessibilityElement
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(isAccessibilityElement);
+  return _getAccessibilityFromViewOrProperty(_isAccessibilityElement, isAccessibilityElement);
 }
 
 - (void)setIsAccessibilityElement:(BOOL)isAccessibilityElement
 {
   _bridge_prologue_write;
-  _setToViewOnly(isAccessibilityElement, isAccessibilityElement);
+  _setAccessibilityToViewAndProperty(_isAccessibilityElement, isAccessibilityElement, isAccessibilityElement, isAccessibilityElement);
 }
 
 - (NSString *)accessibilityLabel
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityLabel);
+  return _getAccessibilityFromViewOrProperty(_accessibilityLabel, accessibilityLabel);
 }
 
 - (void)setAccessibilityLabel:(NSString *)accessibilityLabel
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityLabel, accessibilityLabel);
+  _setAccessibilityToViewAndProperty(_accessibilityLabel, accessibilityLabel, accessibilityLabel, accessibilityLabel);
 }
 
 - (NSString *)accessibilityHint
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityHint);
+  return _getAccessibilityFromViewOrProperty(_accessibilityHint, accessibilityHint);
 }
 
 - (void)setAccessibilityHint:(NSString *)accessibilityHint
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityHint, accessibilityHint);
+  _setAccessibilityToViewAndProperty(_accessibilityHint, accessibilityHint, accessibilityHint, accessibilityHint);
 }
 
 - (NSString *)accessibilityValue
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityValue);
+  return _getAccessibilityFromViewOrProperty(_accessibilityValue, accessibilityValue);
 }
 
 - (void)setAccessibilityValue:(NSString *)accessibilityValue
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityValue, accessibilityValue);
+  _setAccessibilityToViewAndProperty(_accessibilityValue, accessibilityValue, accessibilityValue, accessibilityValue);
 }
 
 - (UIAccessibilityTraits)accessibilityTraits
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityTraits);
+  return _getAccessibilityFromViewOrProperty(_accessibilityTraits, accessibilityTraits);
 }
 
 - (void)setAccessibilityTraits:(UIAccessibilityTraits)accessibilityTraits
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityTraits, accessibilityTraits);
+  _setAccessibilityToViewAndProperty(_accessibilityTraits, accessibilityTraits, accessibilityTraits, accessibilityTraits);
 }
 
 - (CGRect)accessibilityFrame
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityFrame);
+  return _getAccessibilityFromViewOrProperty(_accessibilityFrame, accessibilityFrame);
 }
 
 - (void)setAccessibilityFrame:(CGRect)accessibilityFrame
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityFrame, accessibilityFrame);
+  _setAccessibilityToViewAndProperty(_accessibilityFrame, accessibilityFrame, accessibilityFrame, accessibilityFrame);
 }
 
 - (NSString *)accessibilityLanguage
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityLanguage);
+  return _getAccessibilityFromViewOrProperty(_accessibilityLanguage, accessibilityLanguage);
 }
 
 - (void)setAccessibilityLanguage:(NSString *)accessibilityLanguage
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityLanguage, accessibilityLanguage);
+  _setAccessibilityToViewAndProperty(_accessibilityLanguage, accessibilityLanguage, accessibilityLanguage, accessibilityLanguage);
 }
 
 - (BOOL)accessibilityElementsHidden
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityElementsHidden);
+  return _getAccessibilityFromViewOrProperty(_accessibilityElementsHidden, accessibilityElementsHidden);
 }
 
 - (void)setAccessibilityElementsHidden:(BOOL)accessibilityElementsHidden
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityElementsHidden, accessibilityElementsHidden);
+  _setAccessibilityToViewAndProperty(_accessibilityElementsHidden, accessibilityElementsHidden, accessibilityElementsHidden, accessibilityElementsHidden);
 }
 
 - (BOOL)accessibilityViewIsModal
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityViewIsModal);
+  return _getAccessibilityFromViewOrProperty(_accessibilityViewIsModal, accessibilityViewIsModal);
 }
 
 - (void)setAccessibilityViewIsModal:(BOOL)accessibilityViewIsModal
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityViewIsModal, accessibilityViewIsModal);
+  _setAccessibilityToViewAndProperty(_accessibilityViewIsModal, accessibilityViewIsModal, accessibilityViewIsModal, accessibilityViewIsModal);
 }
 
 - (BOOL)shouldGroupAccessibilityChildren
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(shouldGroupAccessibilityChildren);
+  return _getAccessibilityFromViewOrProperty(_shouldGroupAccessibilityChildren, shouldGroupAccessibilityChildren);
 }
 
 - (void)setShouldGroupAccessibilityChildren:(BOOL)shouldGroupAccessibilityChildren
 {
   _bridge_prologue_write;
-  _setToViewOnly(shouldGroupAccessibilityChildren, shouldGroupAccessibilityChildren);
+  _setAccessibilityToViewAndProperty(_shouldGroupAccessibilityChildren, shouldGroupAccessibilityChildren, shouldGroupAccessibilityChildren, shouldGroupAccessibilityChildren);
 }
 
 - (NSString *)accessibilityIdentifier
 {
   _bridge_prologue_read;
-  return _getFromViewOnly(accessibilityIdentifier);
+  return _getAccessibilityFromViewOrProperty(_accessibilityIdentifier, accessibilityIdentifier);
 }
 
 - (void)setAccessibilityIdentifier:(NSString *)accessibilityIdentifier
 {
   _bridge_prologue_write;
-  _setToViewOnly(accessibilityIdentifier, accessibilityIdentifier);
+  _setAccessibilityToViewAndProperty(_accessibilityIdentifier, accessibilityIdentifier, accessibilityIdentifier, accessibilityIdentifier);
 }
 
 - (NSInteger)accessibilityElementCount
 {
-    _bridge_prologue_read;
-    return _getFromViewOnly(accessibilityElementCount);
+  _bridge_prologue_read;
+  return _getFromViewOnly(accessibilityElementCount);
 }
 
 @end
 
 
+#pragma mark - ASAsyncTransactionContainer
+
 @implementation ASDisplayNode (ASAsyncTransactionContainer)
 
 - (BOOL)asyncdisplaykit_isAsyncTransactionContainer

AsyncDisplayKit/Private/ASDisplayNodeInternal.h

@@ -129,6 +129,19 @@ FOUNDATION_EXPORT NSString * const ASRenderingEngineDidDisplayNodesScheduledBefo
   ASDisplayNodeContextModifier _willDisplayNodeContentWithRenderingContext;
   ASDisplayNodeContextModifier _didDisplayNodeContentWithRenderingContext;
 
+  // Accessibility support
+  BOOL _isAccessibilityElement;
+  NSString *_accessibilityLabel;
+  NSString *_accessibilityHint;
+  NSString *_accessibilityValue;
+  UIAccessibilityTraits _accessibilityTraits;
+  CGRect _accessibilityFrame;
+  NSString *_accessibilityLanguage;
+  BOOL _accessibilityElementsHidden;
+  BOOL _accessibilityViewIsModal;
+  BOOL _shouldGroupAccessibilityChildren;
+  NSString *_accessibilityIdentifier;
+
 #if TIME_DISPLAYNODE_OPS
 @public
   NSTimeInterval _debugTimeToCreateView;