[ASCollectionView][Architecture] Introduce ASSectionContext

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -303,8 +303,13 @@
 		AC3C4A521A1139C100143C57 /* ASCollectionView.mm in Sources */ = {isa = PBXBuildFile; fileRef = AC3C4A501A1139C100143C57 /* ASCollectionView.mm */; };
 		AC47D9421B3B891B00AAEE9D /* ASCellNode.mm in Sources */ = {isa = PBXBuildFile; fileRef = AC6456071B0A335000CF11B8 /* ASCellNode.mm */; };
 		AC47D9461B3BB41900AAEE9D /* ASRelativeSize.mm in Sources */ = {isa = PBXBuildFile; fileRef = AC47D9441B3BB41900AAEE9D /* ASRelativeSize.mm */; };
+		AC6145411D8AFAE8003D62A2 /* ASSection.h in Headers */ = {isa = PBXBuildFile; fileRef = AC6145401D8AFAE8003D62A2 /* ASSection.h */; };
+		AC6145431D8AFD4F003D62A2 /* ASSection.m in Sources */ = {isa = PBXBuildFile; fileRef = AC6145421D8AFD4F003D62A2 /* ASSection.m */; };
+		AC6145441D8AFD4F003D62A2 /* ASSection.m in Sources */ = {isa = PBXBuildFile; fileRef = AC6145421D8AFD4F003D62A2 /* ASSection.m */; };
 		AC6456091B0A335000CF11B8 /* ASCellNode.mm in Sources */ = {isa = PBXBuildFile; fileRef = AC6456071B0A335000CF11B8 /* ASCellNode.mm */; };
 		AC7A2C181BDE11DF0093FE1A /* ASTableViewInternal.h in Headers */ = {isa = PBXBuildFile; fileRef = AC7A2C161BDE11DF0093FE1A /* ASTableViewInternal.h */; };
+		ACE87A2C1D73696800D7FF06 /* ASSectionContext.h in Headers */ = {isa = PBXBuildFile; fileRef = ACE87A2B1D73696800D7FF06 /* ASSectionContext.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		ACE87A331D73726300D7FF06 /* ASSectionContext.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = ACE87A2B1D73696800D7FF06 /* ASSectionContext.h */; };
 		ACF6ED1B1B17843500DA7C62 /* ASBackgroundLayoutSpec.mm in Sources */ = {isa = PBXBuildFile; fileRef = ACF6ED021B17843500DA7C62 /* ASBackgroundLayoutSpec.mm */; };
 		ACF6ED1D1B17843500DA7C62 /* ASCenterLayoutSpec.mm in Sources */ = {isa = PBXBuildFile; fileRef = ACF6ED041B17843500DA7C62 /* ASCenterLayoutSpec.mm */; };
 		ACF6ED211B17843500DA7C62 /* ASDimension.mm in Sources */ = {isa = PBXBuildFile; fileRef = ACF6ED081B17843500DA7C62 /* ASDimension.mm */; };
@@ -657,6 +662,7 @@
 			files = (
 				CC4C2A7A1D8902350039ACAB /* ASTraceEvent.h in CopyFiles */,
 				CC88F7AE1D80AF5E000D6D4E /* ASObjectDescriptionHelpers.h in CopyFiles */,
+				ACE87A331D73726300D7FF06 /* ASSectionContext.h in CopyFiles */,
 				F7CE6C981D2CDB5800BE4C15 /* ASInternalHelpers.h in CopyFiles */,
 				F7CE6CB71D2CE2D000BE4C15 /* ASLayoutableExtensibility.h in CopyFiles */,
 				F7CE6C131D2CDB3E00BE4C15 /* ASPagerFlowLayout.h in CopyFiles */,
@@ -1059,9 +1065,12 @@
 		AC3C4A531A113EEC00143C57 /* ASCollectionViewProtocols.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCollectionViewProtocols.h; sourceTree = "<group>"; };
 		AC47D9431B3BB41900AAEE9D /* ASRelativeSize.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASRelativeSize.h; path = AsyncDisplayKit/Layout/ASRelativeSize.h; sourceTree = "<group>"; };
 		AC47D9441B3BB41900AAEE9D /* ASRelativeSize.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; name = ASRelativeSize.mm; path = AsyncDisplayKit/Layout/ASRelativeSize.mm; sourceTree = "<group>"; };
+		AC6145401D8AFAE8003D62A2 /* ASSection.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASSection.h; path = ../Private/ASSection.h; sourceTree = "<group>"; };
+		AC6145421D8AFD4F003D62A2 /* ASSection.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = ASSection.m; path = ../Private/ASSection.m; sourceTree = "<group>"; };
 		AC6456071B0A335000CF11B8 /* ASCellNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASCellNode.mm; sourceTree = "<group>"; };
 		AC7A2C161BDE11DF0093FE1A /* ASTableViewInternal.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASTableViewInternal.h; sourceTree = "<group>"; };
 		ACC945A81BA9E7A0005E1FB8 /* ASViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASViewController.h; sourceTree = "<group>"; };
+		ACE87A2B1D73696800D7FF06 /* ASSectionContext.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASSectionContext.h; path = Details/ASSectionContext.h; sourceTree = "<group>"; };
 		ACF6ED011B17843500DA7C62 /* ASBackgroundLayoutSpec.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASBackgroundLayoutSpec.h; path = AsyncDisplayKit/Layout/ASBackgroundLayoutSpec.h; sourceTree = "<group>"; };
 		ACF6ED021B17843500DA7C62 /* ASBackgroundLayoutSpec.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; lineEnding = 0; name = ASBackgroundLayoutSpec.mm; path = AsyncDisplayKit/Layout/ASBackgroundLayoutSpec.mm; sourceTree = "<group>"; };
 		ACF6ED031B17843500DA7C62 /* ASCenterLayoutSpec.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASCenterLayoutSpec.h; path = AsyncDisplayKit/Layout/ASCenterLayoutSpec.h; sourceTree = "<group>"; };
@@ -1327,6 +1336,7 @@
 				25E327551C16819500A2170C /* ASPagerNode.m */,
 				A2763D771CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h */,
 				A2763D781CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m */,
+				ACE87A2B1D73696800D7FF06 /* ASSectionContext.h */,
 				D785F6601A74327E00291744 /* ASScrollNode.h */,
 				D785F6611A74327E00291744 /* ASScrollNode.m */,
 				68FC85E01CE29B7E00EDD713 /* ASTabBarController.h */,
@@ -1655,6 +1665,8 @@
 				AC026B681BD57D6F00BBC17E /* ASChangeSetDataController.mm */,
 				E5711A2A1C840C81009619D4 /* ASIndexedNodeContext.h */,
 				E5711A2D1C840C96009619D4 /* ASIndexedNodeContext.mm */,
+				AC6145401D8AFAE8003D62A2 /* ASSection.h */,
+				AC6145421D8AFD4F003D62A2 /* ASSection.m */,
 			);
 			name = "Data Controller";
 			sourceTree = "<group>";
@@ -1799,6 +1811,7 @@
 				18C2ED7F1B9B7DE800F627B3 /* ASCollectionNode.h in Headers */,
 				9C8898BD1C738BB800D6B02E /* ASTextKitFontSizeAdjuster.h in Headers */,
 				B35061F51B010EFD0018CF92 /* ASCollectionView.h in Headers */,
+				ACE87A2C1D73696800D7FF06 /* ASSectionContext.h in Headers */,
 				254C6B791BF94DF4003EC431 /* ASTextKitEntityAttribute.h in Headers */,
 				509E68631B3AEDB4009B9150 /* ASCollectionViewLayoutController.h in Headers */,
 				CC3B20841C3F76D600798563 /* ASPendingStateController.h in Headers */,
@@ -1856,6 +1869,7 @@
 				DE8BEAC21C2DF3FC00D57C12 /* ASDelegateProxy.h in Headers */,
 				B35062041B010EFD0018CF92 /* ASMultiplexImageNode.h in Headers */,
 				B350623E1B010EFD0018CF92 /* _ASAsyncTransactionContainer+Private.h in Headers */,
+				AC6145411D8AFAE8003D62A2 /* ASSection.h in Headers */,
 				DECBD6E81BE56E1900CF4905 /* ASButtonNode.h in Headers */,
 				B35062241B010EFD0018CF92 /* ASMutableAttributedStringBuilder.h in Headers */,
 				B13CA0F81C519EBA00E031AB /* ASCollectionViewLayoutFacilitatorProtocol.h in Headers */,
@@ -2193,6 +2207,7 @@
 				257754B01BEE44CD00737CA5 /* ASTextKitRenderer+TextChecking.mm in Sources */,
 				0516FA411A1563D200B4EBED /* ASMultiplexImageNode.mm in Sources */,
 				DECBD6E91BE56E1900CF4905 /* ASButtonNode.mm in Sources */,
+				AC6145431D8AFD4F003D62A2 /* ASSection.m in Sources */,
 				058D0A1B195D050800B7D73C /* ASMutableAttributedStringBuilder.m in Sources */,
 				055B9FA91A1C154B00035D6D /* ASNetworkImageNode.mm in Sources */,
 				AEB7B01B1C5962EA00662EF4 /* ASDefaultPlayButton.m in Sources */,
@@ -2378,6 +2393,7 @@
 				254C6B821BF94F8A003EC431 /* ASTextKitComponents.m in Sources */,
 				430E7C921B4C23F100697A4C /* ASIndexPath.m in Sources */,
 				34EFC7601B701C8B00AD841F /* ASInsetLayoutSpec.mm in Sources */,
+				AC6145441D8AFD4F003D62A2 /* ASSection.m in Sources */,
 				34EFC75E1B701BF000AD841F /* ASInternalHelpers.m in Sources */,
 				34EFC7681B701CDE00AD841F /* ASLayout.mm in Sources */,
 				DECBD6EA1BE56E1900CF4905 /* ASButtonNode.mm in Sources */,

AsyncDisplayKit/ASCollectionView.h

@@ -20,6 +20,7 @@
 @protocol ASCollectionDataSource;
 @protocol ASCollectionDelegate;
 @protocol ASCollectionViewLayoutInspecting;
+@protocol ASSectionContext;
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -230,6 +231,8 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (void)moveSection:(NSInteger)section toSection:(NSInteger)newSection;
 
+- (nullable id<ASSectionContext>)contextForSection:(NSInteger)section;
+
 /**
  * Inserts items at the locations identified by an array of index paths.
  *
@@ -420,6 +423,8 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (void)collectionViewUnlockDataSource:(ASCollectionView *)collectionView ASDISPLAYNODE_DEPRECATED;
 
+- (nullable id<ASSectionContext>)collectionView:(ASCollectionView *)collectionView contextForSection:(NSInteger)section;
+
 @end
 
 

AsyncDisplayKit/ASCollectionView.mm

@@ -24,6 +24,7 @@
 #import "ASCollectionNode.h"
 #import "_ASDisplayLayer.h"
 #import "ASCollectionViewLayoutFacilitatorProtocol.h"
+#import "ASSectionContext.h"
 
 
 /// What, if any, invalidation should we perform during the next -layoutSubviews.
@@ -154,6 +155,7 @@ @interface ASCollectionView () <ASRangeControllerDataSource, ASRangeControllerDe
     unsigned int asyncDataSourceNodeForItemAtIndexPath:1;
     unsigned int asyncDataSourceNodeBlockForItemAtIndexPath:1;
     unsigned int asyncDataSourceNumberOfSectionsInCollectionView:1;
+    unsigned int asyncDataSourceContextForSection:1;
   } _asyncDataSourceFlags;
 
   struct {
@@ -355,6 +357,7 @@ - (void)setAsyncDataSource:(id<ASCollectionViewDataSource>)asyncDataSource
     _asyncDataSourceFlags.asyncDataSourceNodeForItemAtIndexPath = [_asyncDataSource respondsToSelector:@selector(collectionView:nodeForItemAtIndexPath:)];
     _asyncDataSourceFlags.asyncDataSourceNodeBlockForItemAtIndexPath = [_asyncDataSource respondsToSelector:@selector(collectionView:nodeBlockForItemAtIndexPath:)];
     _asyncDataSourceFlags.asyncDataSourceNumberOfSectionsInCollectionView = [_asyncDataSource respondsToSelector:@selector(numberOfSectionsInCollectionView:)];
+    _asyncDataSourceFlags.asyncDataSourceContextForSection = [_asyncDataSource respondsToSelector:@selector(collectionView:contextForSection:)];
 
     ASDisplayNodeAssert(_asyncDataSourceFlags.asyncDataSourceNodeBlockForItemAtIndexPath
                         || _asyncDataSourceFlags.asyncDataSourceNodeForItemAtIndexPath, @"Data source must implement collectionView:nodeForItemAtIndexPath: or collectionView:nodeBlockForItemAtIndexPath:");
@@ -594,6 +597,12 @@ - (void)moveSection:(NSInteger)section toSection:(NSInteger)newSection
   [_dataController moveSection:section toSection:newSection withAnimationOptions:kASCollectionViewAnimationNone];
 }
 
+- (id<ASSectionContext>)contextForSection:(NSInteger)section
+{
+  ASDisplayNodeAssertMainThread();
+  return [_dataController contextForSection:section];
+}
+
 - (void)insertItemsAtIndexPaths:(NSArray *)indexPaths
 {
   ASDisplayNodeAssertMainThread();
@@ -1000,7 +1009,7 @@ - (NSUInteger)numberOfSectionsInDataController:(ASDataController *)dataControlle
   return self.strongCollectionNode;
 }
 
-#pragma mark - ASCollectionViewDataControllerSource Supplementary view support
+#pragma mark - ASCollectionViewDataControllerSource
 
 - (ASCellNode *)dataController:(ASCollectionDataController *)dataController supplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
 {
@@ -1024,6 +1033,21 @@ - (NSUInteger)dataController:(ASCollectionDataController *)dataController supple
   return [self.layoutInspector collectionView:self supplementaryNodesOfKind:kind inSection:section];
 }
 
+- (id<ASSectionContext>)dataController:(ASDataController *)dataController contextForSection:(NSInteger)section
+{
+  ASDisplayNodeAssertMainThread();
+  id<ASSectionContext> context = nil;
+
+  if (_asyncDataSourceFlags.asyncDataSourceContextForSection) {
+    context = [_asyncDataSource collectionView:self contextForSection:section];
+  }
+
+  if (context != nil) {
+    context.collectionView = self;
+  }
+  return context;
+}
+
 #pragma mark - ASRangeControllerDataSource
 
 - (ASRangeController *)rangeController

AsyncDisplayKit/AsyncDisplayKit.h

@@ -32,6 +32,7 @@
 #import <AsyncDisplayKit/ASCollectionViewFlowLayoutInspector.h>
 #import <AsyncDisplayKit/ASCollectionViewLayoutFacilitatorProtocol.h>
 #import <AsyncDisplayKit/ASCellNode.h>
+#import <AsyncDisplayKit/ASSectionContext.h>
 
 #import <AsyncDisplayKit/ASScrollNode.h>
 

AsyncDisplayKit/Details/ASCollectionDataController.h

@@ -16,6 +16,9 @@
 @class ASDisplayNode;
 @class ASCollectionDataController;
 @protocol ASDataControllerSource;
+@protocol ASSectionContext;
+
+NS_ASSUME_NONNULL_BEGIN
 
 @protocol ASCollectionDataControllerSource <ASDataControllerSource>
 
@@ -28,6 +31,8 @@
 
 - (NSUInteger)dataController:(ASCollectionDataController *)dataController supplementaryNodesOfKind:(NSString *)kind inSection:(NSUInteger)section;
 
+- (nullable id<ASSectionContext>)dataController:(ASCollectionDataController *)dataController contextForSection:(NSInteger)section;
+
 @optional
 
 - (ASCellNode *)dataController:(ASCollectionDataController *)dataController supplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
@@ -42,4 +47,8 @@
 
 - (ASCellNode *)supplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
 
+- (nullable id<ASSectionContext>)contextForSection:(NSInteger)section;
+
 @end
+
+NS_ASSUME_NONNULL_END