A11y for scrollnode

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## master
 * Add your own contributions to the next release on the line below this with your name.
+- [ASScrollNode] A11y support for ASScrollNode. [Max Wang](https://github.com/wsdwsd0829). [#1188](https://github.com/TextureGroup/Texture/pull/1188)
 - [ASDisplayNode.m] Make sure node is loaded before enter visible. [Max Wang](https://github.com/wsdwsd0829). [#886](https://github.com/TextureGroup/Texture/pull/886)
 - [ASTextNode2] Add improved support for all line-break modes in experimental text node. [Kevin Smith](https://github.com/wiseoldduck). [#1150](https://github.com/TextureGroup/Texture/pull/1150)
 - [ASExperimentalFeatures.m] Fix mismatch name in experimental features. [Max Wang](https://github.com/wsdwsd0829). [#1159](https://github.com/TextureGroup/Texture/pull/1159)

Source/ASScrollNode.mm

@@ -52,6 +52,11 @@ - (void)didMoveToWindow
   }
 }
 
+- (NSArray *)accessibilityElements
+{
+  return [self.asyncdisplaykit_node accessibilityElements];
+}
+
 @end
 
 @implementation ASScrollNode

Source/Details/_ASDisplayViewAccessiblity.mm

@@ -131,7 +131,7 @@ static void CollectUIAccessibilityElementsForNode(ASDisplayNode *node, ASDisplay
   });
 }
 
-static void CollectAccessibilityElementsForContainer(ASDisplayNode *container, _ASDisplayView *view, NSMutableArray *elements) {
+static void CollectAccessibilityElementsForContainer(ASDisplayNode *container, UIView *view, NSMutableArray *elements) {
   UIAccessibilityElement *accessiblityElement = [ASAccessibilityElement accessibilityElementWithContainer:view node:container containerNode:container];
 
   NSMutableArray<ASAccessibilityElement *> *labeledNodes = [[NSMutableArray alloc] init];
@@ -195,7 +195,7 @@ static void CollectAccessibilityElementsForContainer(ASDisplayNode *container, _
 }
 
 /// Collect all accessibliity elements for a given view and view node
-static void CollectAccessibilityElementsForView(_ASDisplayView *view, NSMutableArray *elements)
+static void CollectAccessibilityElementsForView(UIView *view, NSMutableArray *elements)
 {
   ASDisplayNodeCAssertNotNil(elements, @"Should pass in a NSMutableArray");
 
@@ -258,17 +258,28 @@ - (NSArray *)accessibilityElements
   if (viewNode == nil) {
     return @[];
   }
-
   if (_accessibilityElements == nil) {
-    NSMutableArray *accessibilityElements = [[NSMutableArray alloc] init];
-    CollectAccessibilityElementsForView(self, accessibilityElements);
-    SortAccessibilityElements(accessibilityElements);
-    _accessibilityElements = accessibilityElements;
+    _accessibilityElements = [viewNode accessibilityElements];
   }
-
   return _accessibilityElements;
 }
 
 @end
 
+@implementation ASDisplayNode (AccessibilityInternal)
+
+- (NSArray *)accessibilityElements
+{
+  if (!self.isNodeLoaded) {
+    ASDisplayNodeFailAssert(@"Cannot access accessibilityElements since node is not loaded");
+    return @[];
+  }
+  NSMutableArray *accessibilityElements = [[NSMutableArray alloc] init];
+  CollectAccessibilityElementsForView(self.view, accessibilityElements);
+  SortAccessibilityElements(accessibilityElements);
+  return accessibilityElements;
+}
+
+@end
+
 #endif

Source/Private/ASDisplayNode+FrameworkPrivate.h

@@ -312,6 +312,10 @@ __unused static NSString * _Nonnull NSStringFromASHierarchyStateChange(ASHierarc
 
 @end
 
+@interface ASDisplayNode (AccessibilityInternal)
+- (NSArray *)accessibilityElements;
+@end;
+
 @interface UIView (ASDisplayNodeInternal)
 @property (nullable, weak) ASDisplayNode *asyncdisplaykit_node;
 @end

Tests/ASScrollNodeTests.m

@@ -132,4 +132,35 @@ - (void)testAutomaticallyManagesContentSizeWithInvalidCalculatedSizeForLayout
   ASXCTAssertEqualSizes(self.scrollNode.view.contentSize, subnodeSize);
 }
 
+- (void)testASScrollNodeAccessibility {
+  ASDisplayNode *scrollNode = [[ASDisplayNode alloc] init];
+  ASDisplayNode *node = [[ASDisplayNode alloc] init];
+  node.isAccessibilityContainer = YES;
+  node.accessibilityLabel = @"node";
+  [scrollNode addSubnode:node];
+  node.frame = CGRectMake(0,0,100,100);
+  ASTextNode2 *text = [[ASTextNode2 alloc] init];
+  text.attributedText = [[NSAttributedString alloc] initWithString:@"text"];
+  [node addSubnode:text];
+
+  ASTextNode2 *text2 = [[ASTextNode2 alloc] init];
+  text2.attributedText = [[NSAttributedString alloc] initWithString:@"text2"];
+  [node addSubnode:text2];
+  __unused UIView *view = scrollNode.view;
+  XCTAssertTrue(node.view.accessibilityElements.firstObject, @"node");
+
+  // Following tests will only pass when accessibility is enabled.
+  // More details: https://github.com/TextureGroup/Texture/pull/1188
+
+  // A bunch of a11y containers each of which hold aggregated labels.
+  /* NSArray *a11yElements = [scrollNode.view accessibilityElements];
+  XCTAssertTrue(a11yElements.count > 0, @"accessibilityElements should exist");
+
+  UIAccessibilityElement *container = a11yElements.firstObject;
+  XCTAssertTrue(container.isAccessibilityElement == false && container.accessibilityElements.count > 0);
+  UIAccessibilityElement *ae = container.accessibilityElements.firstObject;
+  XCTAssertTrue([[ae accessibilityLabel] isEqualToString:@"node, text, text2"]);
+  */
+}
+
 @end