Created ASCollectionNode with new example project.

Eases support for nesting horizontally scrolling elements within a vertical scroller.

Further changes will improve the API, and optimize handling of the nested working ranges.

examples/HorizontalWithinVerticalScrolling/Sample/ViewController.m

@@ -0,0 +1,84 @@
+/* This file provided by Facebook is for non-commercial testing and evaluation
+ * purposes only.  Facebook reserves all rights not expressly granted.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import <AsyncDisplayKit/ASAssert.h>
+
+#import "ViewController.h"
+#import "HorizontalScrollCellNode.h"
+
+@interface ViewController () <ASTableViewDataSource, ASTableViewDelegate>
+{
+  ASTableView *_tableView;
+}
+
+@end
+
+@implementation ViewController
+
+#pragma mark -
+#pragma mark UIViewController.
+
+- (instancetype)init
+{
+  if (!(self = [super init]))
+    return nil;
+
+  _tableView = [[ASTableView alloc] initWithFrame:CGRectZero style:UITableViewStylePlain];
+  _tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
+  _tableView.asyncDataSource = self;
+  _tableView.asyncDelegate = self;
+  
+  self.title = @"Horizontal Scrolling Gradients";
+  self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRedo
+                                                                                         target:self
+                                                                                         action:@selector(reloadEverything)];
+
+  return self;
+}
+
+- (void)reloadEverything
+{
+  [_tableView reloadData];
+}
+
+- (void)viewDidLoad
+{
+  [super viewDidLoad];
+
+  [self.view addSubview:_tableView];
+}
+
+- (void)viewWillLayoutSubviews
+{
+  _tableView.frame = self.view.bounds;
+}
+
+- (BOOL)prefersStatusBarHidden
+{
+  return YES;
+}
+
+#pragma mark -
+#pragma mark ASTableView.
+
+- (ASCellNode *)tableView:(ASTableView *)tableView nodeForRowAtIndexPath:(NSIndexPath *)indexPath
+{
+  HorizontalScrollCellNode *node = [[HorizontalScrollCellNode alloc] initWithElementSize:CGSizeMake(100, 100)];
+  return node;
+}
+
+- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
+{
+  return 100;
+}
+
+@end