Merge pull request #1173 from rahul-malik/rmalik-async-node-alloc

[ASCellNode] Move allocation off the main thread

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -555,8 +555,8 @@
 		054963481A1EA066000F8E56 /* ASBasicImageDownloader.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASBasicImageDownloader.mm; sourceTree = "<group>"; };
 		055B9FA61A1C154B00035D6D /* ASNetworkImageNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASNetworkImageNode.h; sourceTree = "<group>"; };
 		055B9FA71A1C154B00035D6D /* ASNetworkImageNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASNetworkImageNode.mm; sourceTree = "<group>"; };
-		055F1A3219ABD3E3004DAFF1 /* ASTableView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASTableView.h; sourceTree = "<group>"; };
+		055F1A3219ABD3E3004DAFF1 /* ASTableView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = ASTableView.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
-		055F1A3319ABD3E3004DAFF1 /* ASTableView.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASTableView.mm; sourceTree = "<group>"; };
+		055F1A3319ABD3E3004DAFF1 /* ASTableView.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; lineEnding = 0; path = ASTableView.mm; sourceTree = "<group>"; };
 		055F1A3619ABD413004DAFF1 /* ASRangeController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASRangeController.h; sourceTree = "<group>"; };
 		055F1A3719ABD413004DAFF1 /* ASRangeController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASRangeController.mm; sourceTree = "<group>"; };
 		055F1A3A19ABD43F004DAFF1 /* ASCellNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCellNode.h; sourceTree = "<group>"; };
@@ -654,12 +654,12 @@
 		205F0E1F1B376416007741D0 /* CGRect+ASConvenience.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "CGRect+ASConvenience.h"; sourceTree = "<group>"; };
 		205F0E201B376416007741D0 /* CGRect+ASConvenience.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "CGRect+ASConvenience.m"; sourceTree = "<group>"; };
 		242995D21B29743C00090100 /* ASBasicImageDownloaderTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASBasicImageDownloaderTests.m; sourceTree = "<group>"; };
-		251B8EF21BBB3D690087C538 /* ASCollectionDataController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCollectionDataController.h; sourceTree = "<group>"; };
+		251B8EF21BBB3D690087C538 /* ASCollectionDataController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = ASCollectionDataController.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
-		251B8EF31BBB3D690087C538 /* ASCollectionDataController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASCollectionDataController.mm; sourceTree = "<group>"; };
+		251B8EF31BBB3D690087C538 /* ASCollectionDataController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; lineEnding = 0; path = ASCollectionDataController.mm; sourceTree = "<group>"; };
 		251B8EF41BBB3D690087C538 /* ASCollectionViewFlowLayoutInspector.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCollectionViewFlowLayoutInspector.h; sourceTree = "<group>"; };
 		251B8EF51BBB3D690087C538 /* ASCollectionViewFlowLayoutInspector.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASCollectionViewFlowLayoutInspector.m; sourceTree = "<group>"; };
 		251B8EF61BBB3D690087C538 /* ASDataController+Subclasses.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "ASDataController+Subclasses.h"; sourceTree = "<group>"; };
-		2538B6F21BC5D2A2003CA0B4 /* ASCollectionViewFlowLayoutInspectorTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASCollectionViewFlowLayoutInspectorTests.m; sourceTree = "<group>"; };
+		2538B6F21BC5D2A2003CA0B4 /* ASCollectionViewFlowLayoutInspectorTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = ASCollectionViewFlowLayoutInspectorTests.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		254C6B511BF8FE6D003EC431 /* ASTextKitTruncationTests.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASTextKitTruncationTests.mm; sourceTree = "<group>"; };
 		254C6B531BF8FF2A003EC431 /* ASTextKitTests.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASTextKitTests.mm; sourceTree = "<group>"; };
 		2577548F1BED289A00737CA5 /* ASEqualityHashHelpers.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASEqualityHashHelpers.mm; sourceTree = "<group>"; };
@@ -690,8 +690,8 @@
 		257754BD1BEE458E00737CA5 /* ASTextNodeWordKerner.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = ASTextNodeWordKerner.m; path = TextKit/ASTextNodeWordKerner.m; sourceTree = "<group>"; };
 		258FF4251C0D152600A83844 /* ASRangeHandlerVisible.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASRangeHandlerVisible.h; sourceTree = "<group>"; };
 		258FF4261C0D152600A83844 /* ASRangeHandlerVisible.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASRangeHandlerVisible.mm; sourceTree = "<group>"; };
-		25E327541C16819500A2170C /* ASPagerNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASPagerNode.h; sourceTree = "<group>"; };
+		25E327541C16819500A2170C /* ASPagerNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = ASPagerNode.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
-		25E327551C16819500A2170C /* ASPagerNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASPagerNode.m; sourceTree = "<group>"; };
+		25E327551C16819500A2170C /* ASPagerNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = ASPagerNode.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		2911485B1A77147A005D0878 /* ASControlNodeTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASControlNodeTests.m; sourceTree = "<group>"; };
 		292C59991A956527007E5DD6 /* ASLayoutRangeType.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASLayoutRangeType.h; sourceTree = "<group>"; };
 		292C599A1A956527007E5DD6 /* ASRangeHandlerPreload.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASRangeHandlerPreload.h; sourceTree = "<group>"; };
@@ -705,11 +705,11 @@
 		299DA1A71A828D2900162D41 /* ASBatchContext.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASBatchContext.h; sourceTree = "<group>"; };
 		299DA1A81A828D2900162D41 /* ASBatchContext.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASBatchContext.mm; sourceTree = "<group>"; };
 		29CDC2E11AAE70D000833CA4 /* ASBasicImageDownloaderContextTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASBasicImageDownloaderContextTests.m; sourceTree = "<group>"; };
-		3C9C128419E616EF00E942A0 /* ASTableViewTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASTableViewTests.m; sourceTree = "<group>"; };
+		3C9C128419E616EF00E942A0 /* ASTableViewTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = ASTableViewTests.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		430E7C8D1B4C23F100697A4C /* ASIndexPath.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASIndexPath.h; sourceTree = "<group>"; };
 		430E7C8E1B4C23F100697A4C /* ASIndexPath.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASIndexPath.m; sourceTree = "<group>"; };
-		464052191A3F83C40061C0BA /* ASDataController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASDataController.h; sourceTree = "<group>"; };
+		464052191A3F83C40061C0BA /* ASDataController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = ASDataController.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
-		4640521A1A3F83C40061C0BA /* ASDataController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASDataController.mm; sourceTree = "<group>"; };
+		4640521A1A3F83C40061C0BA /* ASDataController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; lineEnding = 0; path = ASDataController.mm; sourceTree = "<group>"; };
 		4640521B1A3F83C40061C0BA /* ASFlowLayoutController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASFlowLayoutController.h; sourceTree = "<group>"; };
 		4640521C1A3F83C40061C0BA /* ASFlowLayoutController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASFlowLayoutController.mm; sourceTree = "<group>"; };
 		4640521D1A3F83C40061C0BA /* ASLayoutController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASLayoutController.h; sourceTree = "<group>"; };
@@ -731,7 +731,7 @@
 		9C8221931BA237B80037F19A /* ASStackBaselinePositionedLayout.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASStackBaselinePositionedLayout.h; sourceTree = "<group>"; };
 		9C8221941BA237B80037F19A /* ASStackBaselinePositionedLayout.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASStackBaselinePositionedLayout.mm; sourceTree = "<group>"; };
 		9CDC18CB1B910E12004965E2 /* ASLayoutablePrivate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASLayoutablePrivate.h; path = AsyncDisplayKit/Layout/ASLayoutablePrivate.h; sourceTree = "<group>"; };
-		9F06E5CC1B4CAF4200F015D8 /* ASCollectionViewTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASCollectionViewTests.m; sourceTree = "<group>"; };
+		9F06E5CC1B4CAF4200F015D8 /* ASCollectionViewTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = ASCollectionViewTests.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		A32FEDD31C501B6A004F642A /* ASTextKitFontSizeAdjuster.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASTextKitFontSizeAdjuster.h; path = TextKit/ASTextKitFontSizeAdjuster.h; sourceTree = "<group>"; };
 		A32FEDD41C501B6A004F642A /* ASTextKitFontSizeAdjuster.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = ASTextKitFontSizeAdjuster.m; path = TextKit/ASTextKitFontSizeAdjuster.m; sourceTree = "<group>"; };
 		A373200E1C571B050011FC94 /* ASTextNode+Beta.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "ASTextNode+Beta.h"; sourceTree = "<group>"; };
@@ -741,8 +741,8 @@
 		AC026B6D1BD57DBF00BBC17E /* _ASHierarchyChangeSet.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = _ASHierarchyChangeSet.h; sourceTree = "<group>"; };
 		AC026B6E1BD57DBF00BBC17E /* _ASHierarchyChangeSet.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = _ASHierarchyChangeSet.m; sourceTree = "<group>"; };
 		AC21EC0F1B3D0BF600C8B19A /* ASStackLayoutDefines.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASStackLayoutDefines.h; path = AsyncDisplayKit/Layout/ASStackLayoutDefines.h; sourceTree = "<group>"; };
-		AC3C4A4F1A1139C100143C57 /* ASCollectionView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCollectionView.h; sourceTree = "<group>"; };
+		AC3C4A4F1A1139C100143C57 /* ASCollectionView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = ASCollectionView.h; sourceTree = "<group>"; };
-		AC3C4A501A1139C100143C57 /* ASCollectionView.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASCollectionView.mm; sourceTree = "<group>"; };
+		AC3C4A501A1139C100143C57 /* ASCollectionView.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; lineEnding = 0; path = ASCollectionView.mm; sourceTree = "<group>"; };
 		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>"; };
@@ -1629,7 +1629,6 @@
 				058D09B9195D04C000B7D73C /* Frameworks */,
 				058D09BA195D04C000B7D73C /* Resources */,
 				3B9D88CDF51B429C8409E4B6 /* Copy Pods Resources */,
-				FB42E06CF915B60406431170 /* Embed Pods Frameworks */,
 			);
 			buildRules = (
 			);
@@ -1759,21 +1758,6 @@
 			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods-AsyncDisplayKitTests/Pods-AsyncDisplayKitTests-resources.sh\"\n";
 			showEnvVarsInLog = 0;
 		};
-		FB42E06CF915B60406431170 /* Embed Pods Frameworks */ = {
-			isa = PBXShellScriptBuildPhase;
-			buildActionMask = 2147483647;
-			files = (
-			);
-			inputPaths = (
-			);
-			name = "Embed Pods Frameworks";
-			outputPaths = (
-			);
-			runOnlyForDeploymentPostprocessing = 0;
-			shellPath = /bin/sh;
-			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods-AsyncDisplayKitTests/Pods-AsyncDisplayKitTests-frameworks.sh\"\n";
-			showEnvVarsInLog = 0;
-		};
 /* End PBXShellScriptBuildPhase section */
 
 /* Begin PBXSourcesBuildPhase section */

AsyncDisplayKit/ASCollectionView.h

@@ -347,14 +347,27 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @param indexPath The index path of the requested node.
  *
- * @returns a node for display at this indexpath.  Must be thread-safe (can be called on the main thread or a background
+ * @returns a node for display at this indexpath. This will be called on the main thread and should
- * queue) and should not implement reuse (it will be called once per row).  Unlike UICollectionView's version, this method
+ *   not implement reuse (it will be called once per row).  Unlike UICollectionView's version,
- * is not called when the row is about to display.
+ *   this method is not called when the row is about to display.
  */
 - (ASCellNode *)collectionView:(ASCollectionView *)collectionView nodeForItemAtIndexPath:(NSIndexPath *)indexPath;
 
+
 @optional
 
+/**
+ *
+ * @param collectionView The sender.
+ *
+ * @param indexPath The index path of the requested node.
+ *
+ * @returns a block that creates the node for display at this indexpath.  
+ *   Must be thread-safe (can be called on the main thread or a background
+ *   queue) and should not implement reuse (it will be called once per row).
+ */
+- (ASCellNodeBlock)collectionView:(ASCollectionView *)collectionView nodeBlockForItemAtIndexPath:(NSIndexPath *)indexPath;
+
 /**
  * Asks the collection view to provide a supplementary node to display in the collection view.
  *

AsyncDisplayKit/ASCollectionView.mm

@@ -77,6 +77,7 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
   BOOL _asyncDelegateImplementsInsetSection;
   BOOL _collectionViewLayoutImplementsInsetSection;
   BOOL _asyncDataSourceImplementsConstrainedSizeForNode;
+  BOOL _asyncDataSourceImplementsNodeBlockForItemAtIndexPath;
   BOOL _queuedNodeSizeUpdate;
   BOOL _isDeallocating;
   
@@ -301,10 +302,12 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
     _asyncDataSource = nil;
     _proxyDataSource = _isDeallocating ? nil : [[ASCollectionViewProxy alloc] initWithTarget:nil interceptor:self];
     _asyncDataSourceImplementsConstrainedSizeForNode = NO;
+    _asyncDataSourceImplementsNodeBlockForItemAtIndexPath = NO;
   } else {
     _asyncDataSource = asyncDataSource;
     _proxyDataSource = [[ASCollectionViewProxy alloc] initWithTarget:_asyncDataSource interceptor:self];
-    _asyncDataSourceImplementsConstrainedSizeForNode = ([_asyncDataSource respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)] ? 1 : 0);
+    _asyncDataSourceImplementsConstrainedSizeForNode = [_asyncDataSource respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)];
+    _asyncDataSourceImplementsNodeBlockForItemAtIndexPath = [_asyncDataSource respondsToSelector:@selector(collectionView:nodeBlockForItemAtIndexPath:)];
   }
   
   super.dataSource = (id<UICollectionViewDataSource>)_proxyDataSource;
@@ -690,6 +693,38 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
   return node;
 }
 
+
+- (ASCellNodeBlock)dataController:(ASDataController *)dataController nodeBlockAtIndexPath:(NSIndexPath *)indexPath
+{
+  if (!_asyncDataSourceImplementsNodeBlockForItemAtIndexPath) {
+    ASCellNode *node = [_asyncDataSource collectionView:self nodeForItemAtIndexPath:indexPath];
+    ASDisplayNodeAssert([node isKindOfClass:ASCellNode.class], @"invalid node class, expected ASCellNode");
+    __weak __typeof__(self) weakSelf = self;
+    return ^{
+      __typeof__(self) strongSelf = weakSelf;
+      [node enterHierarchyState:ASHierarchyStateRangeManaged];
+      if (node.layoutDelegate == nil) {
+        node.layoutDelegate = strongSelf;
+      }
+      return node;
+    };
+  }
+
+  ASCellNodeBlock block = [_asyncDataSource collectionView:self nodeBlockForItemAtIndexPath:indexPath];
+  ASDisplayNodeAssertNotNil(block, @"Invalid block, expected nonnull ASCellNodeBlock");
+  __weak __typeof__(self) weakSelf = self;
+  return ^{
+    __typeof__(self) strongSelf = weakSelf;
+
+    ASCellNode *node = block();
+    [node enterHierarchyState:ASHierarchyStateRangeManaged];
+    if (node.layoutDelegate == nil) {
+      node.layoutDelegate = strongSelf;
+    }
+    return node;
+  };
+}
+
 - (ASSizeRange)dataController:(ASDataController *)dataController constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath
 {
   ASSizeRange constrainedSize = kInvalidSizeRange;

AsyncDisplayKit/ASPagerNode.h

@@ -15,6 +15,12 @@
 
 // This method replaces -collectionView:nodeForItemAtIndexPath:
 - (ASCellNode *)pagerNode:(ASPagerNode *)pagerNode nodeAtIndex:(NSInteger)index;
+
+@optional
+
+// This method replaces -collectionView:nodeBlockForItemAtIndexPath:
+- (ASCellNodeBlock)pagerNode:(ASPagerNode *)pagerNode nodeBlockAtIndex:(NSInteger)index;
+
 @end
 
 @interface ASPagerNode : ASCollectionNode

AsyncDisplayKit/ASPagerNode.m

@@ -16,6 +16,7 @@
   UICollectionViewFlowLayout *_flowLayout;
   ASPagerNodeProxy *_proxy;
   __weak id <ASPagerNodeDataSource> _pagerDataSource;
+  BOOL _pagerDataSourceImplementsNodeBlockAtIndex;
 }
 
 @end
@@ -84,6 +85,16 @@
   return pageNode;
 }
 
+- (ASCellNodeBlock)collectionView:(ASCollectionView *)collectionView nodeBlockAtIndexPath:(NSIndexPath *)indexPath
+{
+  ASDisplayNodeAssert(_pagerDataSource != nil, @"ASPagerNode must have a data source to load nodes to display");
+  if (!_pagerDataSourceImplementsNodeBlockAtIndex) {
+    ASCellNode *node = [_pagerDataSource pagerNode:self nodeAtIndex:indexPath.item];
+    return ^{ return node; };
+  }
+  return [_pagerDataSource pagerNode:self nodeBlockAtIndex:indexPath.item];
+}
+
 - (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
 {
   ASDisplayNodeAssert(_pagerDataSource != nil, @"ASPagerNode must have a data source to load nodes to display");
@@ -106,6 +117,7 @@
 {
   if (pagerDataSource != _pagerDataSource) {
     _pagerDataSource = pagerDataSource;
+    _pagerDataSourceImplementsNodeBlockAtIndex = [_pagerDataSource respondsToSelector:@selector(pagerNode:nodeBlockAtIndex:)];
     _proxy = pagerDataSource ? [[ASPagerNodeProxy alloc] initWithTarget:pagerDataSource interceptor:self] : nil;
     super.dataSource = (id <ASCollectionDataSource>)_proxy;
   }

AsyncDisplayKit/ASTableView.h

@@ -322,14 +322,27 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @param indexPath The index path of the requested node.
  *
- * @returns a node for display at this indexpath.  Must be thread-safe (can be called on the main thread or a background
+ * @returns a node for display at this indexpath. This will be called on the main thread and should not implement reuse (it will be called once per row). Unlike UITableView's version, this method
- * queue) and should not implement reuse (it will be called once per row).  Unlike UITableView's version, this method
  * is not called when the row is about to display.
  */
 - (ASCellNode *)tableView:(ASTableView *)tableView nodeForRowAtIndexPath:(NSIndexPath *)indexPath;
 
 @optional
 
+/**
+ * Similar to -tableView:nodeForRowAtIndexPath:.
+ *
+ * @param tableView The sender.
+ *
+ * @param indexPath The index path of the requested node.
+ *
+ * @returns a block that creates the node for display at this indexpath.  
+ *   Must be thread-safe (can be called on the main thread or a background
+ *   queue) and should not implement reuse (it will be called once per row).
+ */
+
+- (ASCellNodeBlock)tableView:(ASTableView *)tableView nodeBlockForRowAtIndexPath:(NSIndexPath *)indexPath;
+
 /**
  * Indicator to lock the data source for data fetching in async mode.
  * We should not update the data source until the data source has been unlocked. Otherwise, it will incur data inconsistence or exception

AsyncDisplayKit/ASTableView.mm

@@ -876,6 +876,35 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   return node;
 }
 
+- (ASCellNodeBlock)dataController:(ASDataController *)dataController nodeBlockAtIndexPath:(NSIndexPath *)indexPath {
+  if (![_asyncDataSource respondsToSelector:@selector(tableView:nodeBlockForRowAtIndexPath:)]) {
+    ASCellNode *node = [_asyncDataSource tableView:self nodeForRowAtIndexPath:indexPath];
+    ASDisplayNodeAssert([node isKindOfClass:ASCellNode.class], @"invalid node class, expected ASCellNode");
+    __weak __typeof__(self) weakSelf = self;
+    return ^{
+      __typeof__(self) strongSelf = weakSelf;
+      [node enterHierarchyState:ASHierarchyStateRangeManaged];
+      if (node.layoutDelegate == nil) {
+        node.layoutDelegate = strongSelf;
+      }
+      return node;
+    };
+  }
+
+  ASCellNodeBlock block = [_asyncDataSource tableView:self nodeBlockForRowAtIndexPath:indexPath];
+  __weak __typeof__(self) weakSelf = self;
+  ASCellNodeBlock configuredNodeBlock = ^{
+    __typeof__(self) strongSelf = weakSelf;
+    ASCellNode *node = block();
+    [node enterHierarchyState:ASHierarchyStateRangeManaged];
+    if (node.layoutDelegate == nil) {
+      node.layoutDelegate = strongSelf;
+    }
+    return node;
+  };
+  return configuredNodeBlock;
+}
+
 - (ASSizeRange)dataController:(ASDataController *)dataController constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath
 {
   return ASSizeRangeMake(CGSizeMake(_nodesConstrainedWidth, 0),

AsyncDisplayKit/Details/ASCollectionDataController.h

@@ -30,6 +30,10 @@
 
 - (NSUInteger)dataController:(ASCollectionDataController *)dataController supplementaryNodesOfKind:(NSString *)kind inSection:(NSUInteger)section;
 
+@optional
+
+- (ASCellNodeBlock)dataController:(ASCollectionDataController *)dataController supplementaryNodeBlockOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
+
 @end
 
 @interface ASCollectionDataController : ASChangeSetDataController

AsyncDisplayKit/Details/ASCollectionDataController.mm

@@ -17,15 +17,17 @@
 //#define LOG(...) NSLog(__VA_ARGS__)
 #define LOG(...)
 
-@interface ASCollectionDataController ()
+@interface ASCollectionDataController () {
+  BOOL _dataSourceImplementsSupplementaryNodeBlockOfKindAtIndexPath;
+}
 
 - (id<ASCollectionDataControllerSource>)collectionDataSource;
 
 @end
 
 @implementation ASCollectionDataController {
-  NSMutableDictionary *_pendingNodes;
+  NSMutableDictionary<NSString *, NSMutableArray<ASCellNode *> *> *_pendingNodes;
-  NSMutableDictionary *_pendingIndexPaths;
+  NSMutableDictionary<NSString *, NSMutableArray<NSIndexPath *> *> *_pendingIndexPaths;
 }
 
 - (instancetype)initWithAsyncDataFetching:(BOOL)asyncDataFetchingEnabled
@@ -49,7 +51,7 @@
     _pendingIndexPaths[kind] = indexPaths;
     
     // Measure loaded nodes before leaving the main thread
-    [self layoutLoadedNodes:nodes ofKind:kind atIndexPaths:indexPaths];
+    [self batchLayoutNodes:nodes ofKind:kind atIndexPaths:indexPaths completion:nil];
   }
 }
 
@@ -91,7 +93,7 @@
     _pendingIndexPaths[kind] = indexPaths;
     
     // Measure loaded nodes before leaving the main thread
-    [self layoutLoadedNodes:nodes ofKind:kind atIndexPaths:indexPaths];
+    [self batchLayoutNodes:nodes ofKind:kind atIndexPaths:indexPaths completion:nil];
   }
 }
 
@@ -132,7 +134,7 @@
     _pendingIndexPaths[kind] = indexPaths;
     
     // Measure loaded nodes before leaving the main thread
-    [self layoutLoadedNodes:nodes ofKind:kind atIndexPaths:indexPaths];
+    [self batchLayoutNodes:nodes ofKind:kind atIndexPaths:indexPaths completion:nil];
   }
 }
 
@@ -176,7 +178,14 @@
     for (NSUInteger j = 0; j < rowCount; j++) {
       NSIndexPath *indexPath = [sectionIndexPath indexPathByAddingIndex:j];
       [indexPaths addObject:indexPath];
-      [nodes addObject:[self.collectionDataSource dataController:self supplementaryNodeOfKind:kind atIndexPath:indexPath]];
+      ASCellNodeBlock supplementaryCellBlock;
+      if (_dataSourceImplementsSupplementaryNodeBlockOfKindAtIndexPath) {
+        supplementaryCellBlock = [self.collectionDataSource dataController:self supplementaryNodeBlockOfKind:kind atIndexPath:indexPath];
+      } else {
+        ASCellNode *supplementaryNode = [self.collectionDataSource dataController:self supplementaryNodeOfKind:kind atIndexPath:indexPath];
+        supplementaryCellBlock = ^{ return supplementaryNode; };
+      }
+      [nodes addObject:supplementaryCellBlock];
     }
   }
 }
@@ -189,8 +198,14 @@
     for (NSUInteger i = 0; i < rowNum; i++) {
       NSIndexPath *indexPath = [sectionIndex indexPathByAddingIndex:i];
       [indexPaths addObject:indexPath];
-      ASCellNode *supplementaryNode = [self.collectionDataSource dataController:self supplementaryNodeOfKind:kind atIndexPath:indexPath];
+      ASCellNodeBlock supplementaryCellBlock;
-      [nodes addObject:supplementaryNode];
+      if (_dataSourceImplementsSupplementaryNodeBlockOfKindAtIndexPath) {
+        supplementaryCellBlock = [self.collectionDataSource dataController:self supplementaryNodeBlockOfKind:kind atIndexPath:indexPath];
+      } else {
+        ASCellNode *supplementaryNode = [self.collectionDataSource dataController:self supplementaryNodeOfKind:kind atIndexPath:indexPath];
+        supplementaryCellBlock = ^{ return supplementaryNode; };
+      }
+      [nodes addObject:supplementaryCellBlock];
     }
   }];
 }
@@ -236,4 +251,10 @@
   return (id<ASCollectionDataControllerSource>)self.dataSource;
 }
 
+- (void)setDataSource:(id<ASDataControllerSource>)dataSource
+{
+  [super setDataSource:dataSource];
+  _dataSourceImplementsSupplementaryNodeBlockOfKindAtIndexPath = [self.collectionDataSource respondsToSelector:@selector(dataController:supplementaryNodeBlockOfKind:atIndexPath:)];
+}
+
 @end

AsyncDisplayKit/Details/ASDataController.h

@@ -20,12 +20,19 @@ NS_ASSUME_NONNULL_BEGIN
 @class ASDataController;
 
 typedef NSUInteger ASDataControllerAnimationOptions;
+
+/**
+ * ASCellNode creation block. Used to lazily create the ASCellNode instance for a specified indexPath.
+ */
+typedef ASCellNode * _Nonnull(^ASCellNodeBlock)();
+
 FOUNDATION_EXPORT NSString * const ASDataControllerRowNodeKind;
 
 /**
  Data source for data controller
  It will be invoked in the same thread as the api call of ASDataController.
  */
+
 @protocol ASDataControllerSource <NSObject>
 
 /**
@@ -33,6 +40,11 @@ FOUNDATION_EXPORT NSString * const ASDataControllerRowNodeKind;
  */
 - (ASCellNode *)dataController:(ASDataController *)dataController nodeAtIndexPath:(NSIndexPath *)indexPath;
 
+/**
+ Fetch the ASCellNode block for specific index path. This block should return the ASCellNode for the specified index path.
+ */
+- (ASCellNodeBlock)dataController:(ASDataController *)dataController nodeBlockAtIndexPath:(NSIndexPath *)indexPath;
+
 /**
  The constrained size range for layout.
  */

AsyncDisplayKit/Details/ASDataController.mm

@@ -13,11 +13,12 @@
 #import "ASAssert.h"
 #import "ASCellNode.h"
 #import "ASDisplayNode.h"
-#import "ASMainSerialQueue.h"
+#import "ASFlowLayoutController.h"
-#import "ASMultidimensionalArrayUtils.h"
 #import "ASInternalHelpers.h"
 #import "ASLayout.h"
-#import "ASFlowLayoutController.h"
+#import "ASMainSerialQueue.h"
+#import "ASMultidimensionalArrayUtils.h"
+#import "ASThread.h"
 
 //#define LOG(...) NSLog(__VA_ARGS__)
 #define LOG(...)
@@ -39,6 +40,7 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
   NSOperationQueue *_editingTransactionQueue; // Serial background queue.  Dispatches concurrent layout and manages _editingNodes.
   
   BOOL _asyncDataFetchingEnabled;
+
   BOOL _delegateDidInsertNodes;
   BOOL _delegateDidDeleteNodes;
   BOOL _delegateDidInsertSections;
@@ -108,7 +110,7 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
 
 #pragma mark - Cell Layout
 
-- (void)batchLayoutNodes:(NSArray *)nodes ofKind:(NSString *)kind atIndexPaths:(NSArray *)indexPaths completion:(void (^)(NSArray *nodes, NSArray *indexPaths))completionBlock
+- (void)batchLayoutNodes:(NSArray<ASCellNodeBlock> *)nodes ofKind:(NSString *)kind atIndexPaths:(NSArray<NSIndexPath *> *)indexPaths completion:(void (^)(NSArray<ASCellNode *> *nodes, NSArray<NSIndexPath *> *indexPaths))completionBlock
 {
   NSUInteger blockSize = [[ASDataController class] parallelProcessorCount] * kASDataControllerSizingCountPerProcessor;
   
@@ -117,12 +119,11 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
     NSRange batchedRange = NSMakeRange(i, MIN(indexPaths.count - i, blockSize));
     NSArray *batchedIndexPaths = [indexPaths subarrayWithRange:batchedRange];
     NSArray *batchedNodes = [nodes subarrayWithRange:batchedRange];
-    
     [self _layoutNodes:batchedNodes ofKind:kind atIndexPaths:batchedIndexPaths completion:completionBlock];
   }
 }
 
-- (void)layoutLoadedNodes:(NSArray *)nodes ofKind:(NSString *)kind atIndexPaths:(NSArray *)indexPaths {
+- (void)layoutLoadedNodes:(NSArray<ASCellNode *> *)nodes ofKind:(NSString *)kind atIndexPaths:(NSArray<NSIndexPath *> *)indexPaths {
   NSAssert(NSThread.isMainThread, @"Main thread layout must be on the main thread.");
   
   [indexPaths enumerateObjectsUsingBlock:^(NSIndexPath *indexPath, NSUInteger idx, __unused BOOL * stop) {
@@ -159,22 +160,45 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
   if (!nodes.count) {
     return;
   }
-  
+
+  NSUInteger nodeCount = nodes.count;
+  NSMutableArray<ASCellNode *> *allocatedNodes = [NSMutableArray arrayWithCapacity:nodeCount];
   dispatch_group_t layoutGroup = dispatch_group_create();
-  ASSizeRange *nodeBoundSizes = (ASSizeRange *)malloc(sizeof(ASSizeRange) * nodes.count);
+  ASSizeRange *nodeBoundSizes = (ASSizeRange *)malloc(sizeof(ASSizeRange) * nodeCount);
   for (NSUInteger j = 0; j < nodes.count && j < indexPaths.count; j += kASDataControllerSizingCountPerProcessor) {
     NSInteger batchCount = MIN(kASDataControllerSizingCountPerProcessor, indexPaths.count - j);
-    
+
-    for (NSUInteger k = j; k < j + batchCount; k++) {
+
-      ASCellNode *node = nodes[k];
+    dispatch_block_t allocationBlock = ^{
-      if (!node.isNodeLoaded) {
+      for (NSUInteger k = j; k < j + batchCount; k++) {
-        nodeBoundSizes[k] = [self constrainedSizeForNodeOfKind:kind atIndexPath:indexPaths[k]];
+        ASCellNodeBlock cellBlock = nodes[k];
+        ASCellNode *node = cellBlock();
+        ASDisplayNodeAssertNotNil(node, @"Node block created nil node");
+        [allocatedNodes addObject:node];
+        if (!node.isNodeLoaded) {
+          nodeBoundSizes[k] = [self constrainedSizeForNodeOfKind:kind atIndexPath:indexPaths[k]];
+        }
       }
-    }
+    };
     
+    if (ASDisplayNodeThreadIsMain()) {
+      dispatch_semaphore_t sema = dispatch_semaphore_create(0);
+      dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+        allocationBlock();
+        dispatch_semaphore_signal(sema);
+      });
+      dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
+      [self layoutLoadedNodes:allocatedNodes ofKind:kind atIndexPaths:[indexPaths subarrayWithRange:NSMakeRange(j, batchCount)]];
+    } else {
+      allocationBlock();
+      [_mainSerialQueue performBlockOnMainThread:^{
+        [self layoutLoadedNodes:allocatedNodes ofKind:kind atIndexPaths:[indexPaths subarrayWithRange:NSMakeRange(j, batchCount)]];
+      }];
+    }
+
     dispatch_group_async(layoutGroup, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
       for (NSUInteger k = j; k < j + batchCount; k++) {
-        ASCellNode *node = nodes[k];
+        ASCellNode *node = allocatedNodes[k];
         // Only measure nodes whose views aren't loaded, since we're in the background.
         // We should already have measured loaded nodes before we left the main thread, using layoutLoadedNodes:ofKind:atIndexPaths:
         if (!node.isNodeLoaded) {
@@ -183,13 +207,13 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
       }
     });
   }
-  
+
   // Block the _editingTransactionQueue from executing a new edit transaction until layout is done & _editingNodes array is updated.
   dispatch_group_wait(layoutGroup, DISPATCH_TIME_FOREVER);
   free(nodeBoundSizes);
 
   if (completionBlock) {
-    completionBlock(nodes, indexPaths);
+    completionBlock(allocatedNodes, indexPaths);
   }
 }
 
@@ -382,9 +406,6 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
       NSMutableArray *updatedNodes = [NSMutableArray array];
       NSMutableArray *updatedIndexPaths = [NSMutableArray array];
       [self _populateFromEntireDataSourceWithMutableNodes:updatedNodes mutableIndexPaths:updatedIndexPaths];
-      
-      // Measure nodes whose views are loaded before we leave the main thread
-      [self layoutLoadedNodes:updatedNodes ofKind:ASDataControllerRowNodeKind atIndexPaths:updatedIndexPaths];
 
       // Allow subclasses to perform setup before going into the edit transaction
       [self prepareForReloadData];
@@ -409,9 +430,9 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
         }
         
         [self _insertSections:sections atIndexSet:[NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, sectionCount)] withAnimationOptions:animationOptions];
-        
+
         [self _batchLayoutNodes:updatedNodes atIndexPaths:updatedIndexPaths withAnimationOptions:animationOptions];
-        
+
         if (completion) {
           dispatch_async(dispatch_get_main_queue(), completion);
         }
@@ -462,12 +483,11 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
 {
   [indexSet enumerateIndexesUsingBlock:^(NSUInteger idx, BOOL *stop) {
     NSUInteger rowNum = [_dataSource dataController:self rowsInSection:idx];
-    
     NSIndexPath *sectionIndex = [[NSIndexPath alloc] initWithIndex:idx];
     for (NSUInteger i = 0; i < rowNum; i++) {
       NSIndexPath *indexPath = [sectionIndex indexPathByAddingIndex:i];
       [indexPaths addObject:indexPath];
-      [nodes addObject:[_dataSource dataController:self nodeAtIndexPath:indexPath]];
+      [nodes addObject:[_dataSource dataController:self nodeBlockAtIndexPath:indexPath]];
     }
   }];
 }
@@ -482,12 +502,11 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
   NSUInteger sectionNum = [_dataSource numberOfSectionsInDataController:self];
   for (NSUInteger i = 0; i < sectionNum; i++) {
     NSIndexPath *sectionIndexPath = [[NSIndexPath alloc] initWithIndex:i];
-    
     NSUInteger rowNum = [_dataSource dataController:self rowsInSection:i];
     for (NSUInteger j = 0; j < rowNum; j++) {
       NSIndexPath *indexPath = [sectionIndexPath indexPathByAddingIndex:j];
       [indexPaths addObject:indexPath];
-      [nodes addObject:[_dataSource dataController:self nodeAtIndexPath:indexPath]];
+      [nodes addObject:[_dataSource dataController:self nodeBlockAtIndexPath:indexPath]];
     }
   }
 }
@@ -577,9 +596,6 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
       NSMutableArray *updatedNodes = [NSMutableArray array];
       NSMutableArray *updatedIndexPaths = [NSMutableArray array];
       [self _populateFromDataSourceWithSectionIndexSet:sections mutableNodes:updatedNodes mutableIndexPaths:updatedIndexPaths];
-      
-      // Measure nodes whose views are loaded before we leave the main thread
-      [self layoutLoadedNodes:updatedNodes ofKind:ASDataControllerRowNodeKind atIndexPaths:updatedIndexPaths];
 
       [self prepareForInsertSections:sections];
       
@@ -591,7 +607,7 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
         for (NSUInteger i = 0; i < sections.count; i++) {
           [sectionArray addObject:[NSMutableArray array]];
         }
-        
+
         [self _insertSections:sectionArray atIndexSet:sections withAnimationOptions:animationOptions];
         [self _batchLayoutNodes:updatedNodes atIndexPaths:updatedIndexPaths withAnimationOptions:animationOptions];
       }];
@@ -632,13 +648,6 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
       NSMutableArray *updatedIndexPaths = [NSMutableArray array];
       [self _populateFromDataSourceWithSectionIndexSet:sections mutableNodes:updatedNodes mutableIndexPaths:updatedIndexPaths];
 
-      // Dispatch to sizing queue in order to guarantee that any in-progress sizing operations from prior edits have completed.
-      // For example, if an initial -reloadData call is quickly followed by -reloadSections, sizing the initial set may not be done
-      // at this time.  Thus _editingNodes could be empty and crash in ASIndexPathsForMultidimensional[...]
-      
-      // Measure nodes whose views are loaded before we leave the main thread
-      [self layoutLoadedNodes:updatedNodes ofKind:ASDataControllerRowNodeKind atIndexPaths:updatedIndexPaths];
-
       [self prepareForReloadSections:sections];
       
       [_editingTransactionQueue addOperationWithBlock:^{
@@ -649,7 +658,7 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
         LOG(@"Edit Transaction - reloadSections: updatedIndexPaths: %@, indexPaths: %@, _editingNodes: %@", updatedIndexPaths, indexPaths, ASIndexPathsForMultidimensionalArray(_editingNodes[ASDataControllerRowNodeKind]));
         
         [self _deleteNodesAtIndexPaths:indexPaths withAnimationOptions:animationOptions];
-        
+
         // reinsert the elements
         [self _batchLayoutNodes:updatedNodes atIndexPaths:updatedIndexPaths withAnimationOptions:animationOptions];
       }];
@@ -747,12 +756,9 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
       NSArray *sortedIndexPaths = [indexPaths sortedArrayUsingSelector:@selector(compare:)];
       NSMutableArray *nodes = [[NSMutableArray alloc] initWithCapacity:indexPaths.count];
       for (NSUInteger i = 0; i < sortedIndexPaths.count; i++) {
-        [nodes addObject:[_dataSource dataController:self nodeAtIndexPath:sortedIndexPaths[i]]];
+        [nodes addObject:[_dataSource dataController:self nodeBlockAtIndexPath:sortedIndexPaths[i]]];
       }
-      
+
-      // Measure nodes whose views are loaded before we leave the main thread
-      [self layoutLoadedNodes:nodes ofKind:ASDataControllerRowNodeKind atIndexPaths:indexPaths];
-      
       [_editingTransactionQueue addOperationWithBlock:^{
         LOG(@"Edit Transaction - insertRows: %@", indexPaths);
         [self _batchLayoutNodes:nodes atIndexPaths:indexPaths withAnimationOptions:animationOptions];
@@ -797,11 +803,8 @@ static void *kASSizingQueueContext = &kASSizingQueueContext;
       [indexPaths sortedArrayUsingSelector:@selector(compare:)];
       
       for (NSIndexPath *indexPath in indexPaths) {
-        [nodes addObject:[_dataSource dataController:self nodeAtIndexPath:indexPath]];
+        [nodes addObject:[_dataSource dataController:self nodeBlockAtIndexPath:indexPath]];
       }
-      
-      // Measure nodes whose views are loaded before we leave the main thread
-      [self layoutLoadedNodes:nodes ofKind:ASDataControllerRowNodeKind atIndexPaths:indexPaths];
 
       [_editingTransactionQueue addOperationWithBlock:^{
         LOG(@"Edit Transaction - reloadRows: %@", indexPaths);

AsyncDisplayKit/Details/ASDelegateProxy.m

@@ -81,8 +81,8 @@
 @end
 
 @implementation ASDelegateProxy {
-  id <NSObject> __weak _target;
   id <ASDelegateProxyInterceptor> __weak _interceptor;
+  id <NSObject> __weak _target;
 }
 
 - (instancetype)initWithTarget:(id <NSObject>)target interceptor:(id <ASDelegateProxyInterceptor>)interceptor

AsyncDisplayKitTests/ASCollectionViewFlowLayoutInspectorTests.m

@@ -25,6 +25,11 @@
   return [[ASCellNode alloc] init];
 }
 
+- (ASCellNodeBlock)collectionView:(ASCollectionView *)collectionView nodeBlockAtIndexPath:(NSIndexPath *)indexPath
+{
+  return ^{ return [[ASCellNode alloc] init]; };
+}
+
 - (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
 {
   return 0;

AsyncDisplayKitTests/ASCollectionViewTests.m

@@ -35,6 +35,15 @@
   return textCellNode;
 }
 
+
+- (ASCellNodeBlock)collectionView:(ASCollectionView *)collectionView nodeBlockAtIndexPath:(NSIndexPath *)indexPath {
+  return ^{
+    ASTextCellNode *textCellNode = [ASTextCellNode new];
+    textCellNode.text = indexPath.description;
+    return textCellNode;
+  };
+}
+
 - (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
   return self.numberOfSections;
 }

AsyncDisplayKitTests/ASTableViewTests.m

@@ -72,6 +72,11 @@
   return nil;
 }
 
+- (ASCellNodeBlock)tableView:(ASTableView *)tableView nodeBlockForRowAtIndexPath:(NSIndexPath *)indexPath
+{
+  return nil;
+}
+
 - (void)dealloc
 {
   if (_willDeallocBlock) {
@@ -121,6 +126,16 @@
   return textCellNode;
 }
 
+
+- (ASCellNodeBlock)tableView:(ASTableView *)tableView nodeBlockForRowAtIndexPath:(NSIndexPath *)indexPath
+{
+  return ^{
+    ASTestTextCellNode *textCellNode = [ASTestTextCellNode new];
+    textCellNode.text = indexPath.description;
+    return textCellNode;
+  };
+}
+
 @end
 
 @interface ASTableViewTests : XCTestCase