Fix fetch call won't occur for content smaller than bounds unless user scrolls

AsyncDisplayKit/ASCollectionView.mm

@@ -703,6 +703,19 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
 #pragma mark -
 #pragma mark Batch Fetching
 
+- (void)_checkForBatchFetching
+{
+  // Dragging will be handled in scrollViewWillEndDragging:withVelocity:targetContentOffset:
+  if ([self isDragging] || [self isTracking] || ![self _shouldBatchFetch]) {
+    return;
+  }
+  
+  // Check if we should batch fetch
+  if (ASDisplayShouldFetchBatchForContext(_batchContext, [self scrollableDirections], self.bounds, self.contentSize, self.contentOffset, _leadingScreensForBatching)) {
+    [self _beginBatchFetching];
+  }
+}
+
 - (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset
 {
   _deceleratingVelocity = CGPointMake(
@@ -711,7 +724,7 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
   );
 
   if (targetContentOffset != NULL) {
-    [self handleBatchFetchScrollingToOffset:*targetContentOffset];
+    [self _handleBatchFetchScrollingToOffset:*targetContentOffset];
   }
   
   if ([_asyncDelegate respondsToSelector:@selector(scrollViewWillEndDragging:withVelocity:targetContentOffset:)]) {
@@ -738,7 +751,7 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
   }
 }
 
-- (BOOL)shouldBatchFetch
+- (BOOL)_shouldBatchFetch
 {
   // if the delegate does not respond to this method, there is no point in starting to fetch
   BOOL canFetch = [_asyncDelegate respondsToSelector:@selector(collectionView:willBeginBatchFetchWithContext:)];
@@ -749,21 +762,26 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
   }
 }
 
-- (void)handleBatchFetchScrollingToOffset:(CGPoint)targetOffset
+- (void)_handleBatchFetchScrollingToOffset:(CGPoint)targetOffset
 {
   ASDisplayNodeAssert(_batchContext != nil, @"Batch context should exist");
   
-  if (![self shouldBatchFetch]) {
+  if (![self _shouldBatchFetch]) {
     return;
   }
   
   if (ASDisplayShouldFetchBatchForContext(_batchContext, [self scrollDirection], self.bounds, self.contentSize, targetOffset, _leadingScreensForBatching)) {
+    [self _beginBatchFetching];
+  }
+}
+
+- (void)_beginBatchFetching
+{
   [_batchContext beginBatchFetching];
   dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
     [_asyncDelegate collectionView:self willBeginBatchFetchWithContext:_batchContext];
   });
 }
-}
 
 
 #pragma mark - ASDataControllerSource
@@ -975,9 +993,11 @@ static NSString * const kCellReuseIdentifier = @"_ASCollectionViewCell";
     }];
   } else {
     [_layoutFacilitator collectionViewWillEditCellsAtIndexPaths:indexPaths batched:NO];
-    [UIView performWithoutAnimation:^{
+    ASPerformBlockWithoutAnimationCompletion(YES, ^{
       [super insertItemsAtIndexPaths:indexPaths];
-    }];
+    }, ^{
+      
+    });
   }
 }
 

AsyncDisplayKit/ASTableView.mm

@@ -587,18 +587,46 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   } else {
     scrollVelocity = _deceleratingVelocity;
   }
+  
   ASScrollDirection scrollDirection = [self _scrollDirectionForVelocity:scrollVelocity];
   return ASScrollDirectionApplyTransform(scrollDirection, self.transform);
 }
 
-- (ASScrollDirection)_scrollDirectionForVelocity:(CGPoint)velocity
+- (ASScrollDirection)scrollableDirections
+{
+  ASScrollDirection scrollableDirection = ASScrollDirectionNone;
+  CGFloat totalContentWidth = self.contentSize.width + self.contentInset.left + self.contentInset.right;
+  CGFloat totalContentHeight = self.contentSize.height + self.contentInset.top + self.contentInset.bottom;
+  
+  if (self.alwaysBounceHorizontal || totalContentWidth > self.bounds.size.width) { // Can scroll horizontally.
+    scrollableDirection |= ASScrollDirectionHorizontalDirections;
+  }
+  if (self.alwaysBounceVertical || totalContentHeight > self.bounds.size.height) { // Can scroll vertically.
+    scrollableDirection |= ASScrollDirectionVerticalDirections;
+  }
+  return scrollableDirection;
+}
+
+- (ASScrollDirection)_scrollDirectionForVelocity:(CGPoint)scrollVelocity
 {
   ASScrollDirection direction = ASScrollDirectionNone;
-  if (velocity.y < 0.0) {
+  ASScrollDirection scrollableDirections = [self scrollableDirections];
-    direction = ASScrollDirectionDown;
+  
-  } else if (velocity.y > 0.0) {
+  if (ASScrollDirectionContainsHorizontalDirection(scrollableDirections)) { // Can scroll horizontally.
-    direction = ASScrollDirectionUp;
+    if (scrollVelocity.x < 0.0) {
+      direction |= ASScrollDirectionRight;
+    } else if (scrollVelocity.x > 0.0) {
+      direction |= ASScrollDirectionLeft;
     }
+  }
+  if (ASScrollDirectionContainsVerticalDirection(scrollableDirections)) { // Can scroll vertically.
+    if (scrollVelocity.y < 0.0) {
+      direction |= ASScrollDirectionDown;
+    } else if (scrollVelocity.y > 0.0) {
+      direction |= ASScrollDirectionUp;
+    }
+  }
+  
   return direction;
 }
 
@@ -631,7 +659,7 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
     [_asyncDelegate tableView:self willDisplayNodeForRowAtIndexPath:indexPath];
   }
   
-  [_rangeController visibleNodeIndexPathsDidChangeWithScrollDirection:self.scrollDirection];
+  [_rangeController visibleNodeIndexPathsDidChangeWithScrollDirection:[self scrollDirection]];
 
   if (cellNode.neverShowPlaceholders) {
     [cellNode recursivelyEnsureDisplaySynchronously:YES];
@@ -650,7 +678,7 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   
   ASCellNode *cellNode = [cell node];
 
-  [_rangeController visibleNodeIndexPathsDidChangeWithScrollDirection:self.scrollDirection];
+  [_rangeController visibleNodeIndexPathsDidChangeWithScrollDirection:[self scrollDirection]];
 
   if ([_asyncDelegate respondsToSelector:@selector(tableView:didEndDisplayingNode:forRowAtIndexPath:)]) {
     ASDisplayNodeAssertNotNil(cellNode, @"Expected node associated with removed cell not to be nil.");
@@ -675,6 +703,19 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
 #pragma mark - 
 #pragma mark Batch Fetching
 
+- (void)_checkForBatchFetching
+{
+  // Dragging will be handled in scrollViewWillEndDragging:withVelocity:targetContentOffset:
+  if ([self isDragging] || [self isTracking] || ![self _shouldBatchFetch]) {
+    return;
+  }
+  
+  // Check if we should batch fetch
+  if (ASDisplayShouldFetchBatchForContext(_batchContext, [self scrollableDirections], self.bounds, self.contentSize, self.contentOffset, _leadingScreensForBatching)) {
+    [self _beginBatchFetching];
+  }
+}
+
 - (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset
 {
   _deceleratingVelocity = CGPointMake(
@@ -683,7 +724,7 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   );
 
   if (targetContentOffset != NULL) {
-    [self handleBatchFetchScrollingToOffset:*targetContentOffset];
+    [self _handleBatchFetchScrollingToOffset:*targetContentOffset];
   }
 
   if ([_asyncDelegate respondsToSelector:@selector(scrollViewWillEndDragging:withVelocity:targetContentOffset:)]) {
@@ -691,7 +732,20 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   }
 }
 
-- (BOOL)shouldBatchFetch
+- (void)_handleBatchFetchScrollingToOffset:(CGPoint)targetOffset
+{
+  ASDisplayNodeAssert(_batchContext != nil, @"Batch context should exist");
+
+  if (![self _shouldBatchFetch]) {
+    return;
+  }
+
+  if (ASDisplayShouldFetchBatchForContext(_batchContext, [self scrollDirection], self.bounds, self.contentSize, targetOffset, _leadingScreensForBatching)) {
+    [self _beginBatchFetching];
+  }
+}
+
+- (BOOL)_shouldBatchFetch
 {
   // if the delegate does not respond to this method, there is no point in starting to fetch
   BOOL canFetch = [_asyncDelegate respondsToSelector:@selector(tableView:willBeginBatchFetchWithContext:)];
@@ -702,21 +756,13 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   }
 }
 
-- (void)handleBatchFetchScrollingToOffset:(CGPoint)targetOffset
+- (void)_beginBatchFetching
 {
-  ASDisplayNodeAssert(_batchContext != nil, @"Batch context should exist");
-
-  if (![self shouldBatchFetch]) {
-    return;
-  }
-
-  if (ASDisplayShouldFetchBatchForContext(_batchContext, [self scrollDirection], self.bounds, self.contentSize, targetOffset, _leadingScreensForBatching)) {
   [_batchContext beginBatchFetching];
   dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
     [_asyncDelegate tableView:self willBeginBatchFetchWithContext:_batchContext];
   });
 }
-}
 
 #pragma mark - ASRangeControllerDataSource
 
@@ -855,8 +901,13 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   }
   
   BOOL preventAnimation = animationOptions == UITableViewRowAnimationNone;
-  ASPerformBlockWithoutAnimation(preventAnimation, ^{
+  ASPerformBlockWithoutAnimationCompletion(preventAnimation, ^{
     [super insertRowsAtIndexPaths:indexPaths withRowAnimation:(UITableViewRowAnimation)animationOptions];
+  }, ^{
+    // Push this to the next runloop to be sure the UITableView has the right content size
+    dispatch_async(dispatch_get_main_queue(), ^{
+      [self _checkForBatchFetching];
+    });
   });
 
   if (_automaticallyAdjustsContentOffset) {
@@ -874,8 +925,13 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   }
 
   BOOL preventAnimation = animationOptions == UITableViewRowAnimationNone;
-  ASPerformBlockWithoutAnimation(preventAnimation, ^{
+  ASPerformBlockWithoutAnimationCompletion(preventAnimation, ^{
     [super deleteRowsAtIndexPaths:indexPaths withRowAnimation:(UITableViewRowAnimation)animationOptions];
+  }, ^{
+    // Push this to the next runloop to be sure the UITableView has the right content size
+    dispatch_async(dispatch_get_main_queue(), ^{
+      [self _checkForBatchFetching];
+    });
   });
 
   if (_automaticallyAdjustsContentOffset) {
@@ -1077,7 +1133,7 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   // Updating the visible node index paths only for not range managed nodes. Range managed nodes will get their
   // their update in the layout pass
   if (![node supportsRangeManagedInterfaceState]) {
-    [_rangeController visibleNodeIndexPathsDidChangeWithScrollDirection:self.scrollDirection];
+    [_rangeController visibleNodeIndexPathsDidChangeWithScrollDirection:[self scrollDirection]];
   }
 }
 

AsyncDisplayKit/Details/ASBatchContext.h

@@ -33,6 +33,14 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (void)completeBatchFetching:(BOOL)didComplete;
 
+/**
+ * Let the context object know that a batch fetch was completed.
+ *
+ * @discussion For instance, when a table has reached the end of its data, a batch fetch will be attempted unless the context
+ * object thinks that it is still fetching.
+ */
+- (void)completeBatchFetching;
+
 /**
  * Ask the context object if the batch fetching process was cancelled by the context owner.
  *

AsyncDisplayKit/Details/ASBatchContext.mm

@@ -45,24 +45,31 @@ typedef NS_ENUM(NSInteger, ASBatchContextState) {
   return _state == ASBatchContextStateCancelled;
 }
 
-- (void)completeBatchFetching:(BOOL)didComplete
-{
-  if (didComplete) {
-    ASDN::MutexLocker l(_propertyLock);
-    _state = ASBatchContextStateCompleted;
-  }
-}
-
 - (void)beginBatchFetching
 {
   ASDN::MutexLocker l(_propertyLock);
   _state = ASBatchContextStateFetching;
 }
 
+- (void)completeBatchFetching
+{
+  ASDN::MutexLocker l(_propertyLock);
+  _state = ASBatchContextStateCompleted;
+}
+
 - (void)cancelBatchFetching
 {
   ASDN::MutexLocker l(_propertyLock);
   _state = ASBatchContextStateCancelled;
 }
 
+#pragma mark - Deprecated
+
+- (void)completeBatchFetching:(BOOL)didComplete
+{
+  if (didComplete) {
+    [self completeBatchFetching];
+  }
+}
+
 @end

AsyncDisplayKit/Private/ASBatchFetching.m

@@ -20,7 +20,7 @@ BOOL ASDisplayShouldFetchBatchForContext(ASBatchContext *context,
   }
 
   // only Down and Right scrolls are currently supported (tail loading)
-  if (scrollDirection != ASScrollDirectionDown && scrollDirection != ASScrollDirectionRight) {
+  if (!ASScrollDirectionContainsDown(scrollDirection) && !ASScrollDirectionContainsRight(scrollDirection)) {
     return NO;
   }
 
@@ -31,11 +31,11 @@ BOOL ASDisplayShouldFetchBatchForContext(ASBatchContext *context,
 
   CGFloat viewLength, offset, contentLength;
 
-  if (scrollDirection == ASScrollDirectionDown) {
+  if (ASScrollDirectionContainsDown(scrollDirection)) {
     viewLength = bounds.size.height;
     offset = targetOffset.y;
     contentLength = contentSize.height;
-  } else { // horizontal
+  } else { // horizontal / right
     viewLength = bounds.size.width;
     offset = targetOffset.x;
     contentLength = contentSize.width;

AsyncDisplayKit/Private/ASInternalHelpers.h

@@ -32,6 +32,26 @@ BOOL ASRunningOnOS7();
 
 ASDISPLAYNODE_EXTERN_C_END
 
+/**
+ @summary Conditionally performs UIView geometry changes in the given block without animation and call completion block afterwards.
+ 
+ Used primarily to circumvent UITableView forcing insertion animations when explicitly told not to via
+ `UITableViewRowAnimationNone`. More info: https://github.com/facebook/AsyncDisplayKit/pull/445
+ 
+ @param withoutAnimation Set to `YES` to perform given block without animation
+ @param block Perform UIView geometry changes within the passed block
+ @param completion Call completion block if UIView geometry changes within the passed block did complete
+ */
+ASDISPLAYNODE_INLINE void ASPerformBlockWithoutAnimationCompletion(BOOL withoutAnimation, void (^block)(), void (^completion)()) {
+  [CATransaction begin];
+  [CATransaction setDisableActions:withoutAnimation];
+  if (completion != nil) {
+    [CATransaction setCompletionBlock:completion];
+  }
+  block();
+  [CATransaction commit];
+}
+
 /**
  @summary Conditionally performs UIView geometry changes in the given block without animation.
  
@@ -42,11 +62,7 @@ ASDISPLAYNODE_EXTERN_C_END
  @param block Perform UIView geometry changes within the passed block
  */
 ASDISPLAYNODE_INLINE void ASPerformBlockWithoutAnimation(BOOL withoutAnimation, void (^block)()) {
-  if (withoutAnimation) {
+  ASPerformBlockWithoutAnimationCompletion(withoutAnimation, block, nil);
-    [UIView performWithoutAnimation:block];
-  } else {
-    block();
-  }
 }
 
 ASDISPLAYNODE_INLINE void ASBoundsAndPositionForFrame(CGRect rect, CGPoint origin, CGPoint anchorPoint, CGRect *bounds, CGPoint *position)

examples/Kittens/Sample/ViewController.m

@@ -177,7 +177,7 @@ static const NSInteger kMaxLitterSize = 100;        // max number of kitten cell
     [_kittenDataSource addObjectsFromArray:moarKittens];
     [tableView insertRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationFade];
 
-    [context completeBatchFetching:YES];
+    [context completeBatchFetching];
   });
 }