Add 'submodules/AsyncDisplayKit/' from commit '02bedc12816e251ad71777f9d2578329b6d2bef6'

git-subtree-dir: submodules/AsyncDisplayKit
git-subtree-mainline: d06f423e0e
git-subtree-split: 02bedc1281

submodules/AsyncDisplayKit/examples/CatDealsCollectionView/Sample/ViewController.m

@@ -0,0 +1,221 @@
+//
+//  ViewController.m
+//  Texture
+//
+//  Copyright (c) Facebook, Inc. and its affiliates.  All rights reserved.
+//  Changes after 4/13/2017 are: Copyright (c) Pinterest, Inc.  All rights reserved.
+//  Licensed under Apache 2.0: http://www.apache.org/licenses/LICENSE-2.0
+//
+
+#import "ViewController.h"
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import "ItemNode.h"
+#import "BlurbNode.h"
+#import "LoadingNode.h"
+
+static const NSTimeInterval kWebResponseDelay = 1.0;
+static const BOOL kSimulateWebResponse = YES;
+static const NSInteger kBatchSize = 20;
+
+static const CGFloat kHorizontalSectionPadding = 10.0f;
+
+@interface ViewController () <ASCollectionDataSource, ASCollectionDelegate, ASCollectionDelegateFlowLayout>
+{
+  ASCollectionNode *_collectionNode;
+  NSMutableArray *_data;
+}
+
+@end
+
+
+@implementation ViewController
+
+#pragma mark -
+#pragma mark UIViewController.
+
+- (instancetype)init
+{
+  UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
+  _collectionNode = [[ASCollectionNode alloc] initWithCollectionViewLayout:layout];
+
+  self = [super initWithNode:_collectionNode];
+  
+  if (self) {
+    self.title = @"Cat Deals";
+  
+    _collectionNode.dataSource = self;
+    _collectionNode.delegate = self;
+    _collectionNode.backgroundColor = [UIColor grayColor];
+    _collectionNode.accessibilityIdentifier = @"Cat deals list";
+    
+    ASRangeTuningParameters preloadTuning;
+    preloadTuning.leadingBufferScreenfuls = 2;
+    preloadTuning.trailingBufferScreenfuls = 1;
+    [_collectionNode setTuningParameters:preloadTuning forRangeType:ASLayoutRangeTypePreload];
+    
+    ASRangeTuningParameters displayTuning;
+    displayTuning.leadingBufferScreenfuls = 1;
+    displayTuning.trailingBufferScreenfuls = 0.5;
+    [_collectionNode setTuningParameters:displayTuning forRangeType:ASLayoutRangeTypeDisplay];
+    
+    [_collectionNode registerSupplementaryNodeOfKind:UICollectionElementKindSectionHeader];
+    [_collectionNode registerSupplementaryNodeOfKind:UICollectionElementKindSectionFooter];
+    
+    _data = [[NSMutableArray alloc] init];
+    
+    self.navigationItem.leftItemsSupplementBackButton = YES;
+    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self action:@selector(reloadTapped)];
+  }
+  
+  return self;
+}
+
+- (void)viewDidLoad
+{
+  [super viewDidLoad];
+  
+  // set any collectionView properties here (once the node's backing view is loaded)
+  _collectionNode.leadingScreensForBatching = 2;
+  [self fetchMoreCatsWithCompletion:nil];
+}
+
+- (void)fetchMoreCatsWithCompletion:(void (^)(BOOL))completion
+{
+  if (kSimulateWebResponse) {
+    __weak typeof(self) weakSelf = self;
+    void(^mockWebService)() = ^{
+      NSLog(@"ViewController \"got data from a web service\"");
+      ViewController *strongSelf = weakSelf;
+      if (strongSelf != nil)
+      {
+        [strongSelf appendMoreItems:kBatchSize completion:completion];
+      }
+      else {
+        NSLog(@"ViewController is nil - won't update collection");
+      }
+    };
+    
+    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(kWebResponseDelay * NSEC_PER_SEC)), dispatch_get_main_queue(), mockWebService);
+  } else {
+    [self appendMoreItems:kBatchSize completion:completion];
+  }
+}
+
+- (void)appendMoreItems:(NSInteger)numberOfNewItems completion:(void (^)(BOOL))completion
+{
+  NSArray *newData = [self getMoreData:numberOfNewItems];
+  [_collectionNode performBatchAnimated:YES updates:^{
+    [_data addObjectsFromArray:newData];
+    NSArray *addedIndexPaths = [self indexPathsForObjects:newData];
+    [_collectionNode insertItemsAtIndexPaths:addedIndexPaths];
+  } completion:completion];
+}
+
+- (NSArray *)getMoreData:(NSInteger)count
+{
+  NSMutableArray *data = [NSMutableArray array];
+  for (int i = 0; i < count; i++) {
+    [data addObject:[ItemViewModel randomItem]];
+  }
+  return data;
+}
+
+- (NSArray *)indexPathsForObjects:(NSArray *)data
+{
+  NSMutableArray *indexPaths = [NSMutableArray array];
+  NSInteger section = 0;
+  for (ItemViewModel *viewModel in data) {
+    NSInteger item = [_data indexOfObject:viewModel];
+    NSAssert(item < [_data count] && item != NSNotFound, @"Item should be in _data");
+    [indexPaths addObject:[NSIndexPath indexPathForItem:item inSection:section]];
+  }
+  return indexPaths;
+}
+
+- (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator
+{
+  [_collectionNode.view.collectionViewLayout invalidateLayout];
+}
+
+- (void)reloadTapped
+{
+  [_collectionNode reloadData];
+}
+
+#pragma mark - ASCollectionNodeDelegate / ASCollectionNodeDataSource
+
+- (ASCellNodeBlock)collectionNode:(ASCollectionNode *)collectionNode nodeBlockForItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  return ^{
+    return [[ItemNode alloc] init];
+  };
+}
+
+- (id)collectionNode:(ASCollectionNode *)collectionNode nodeModelForItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  return _data[indexPath.item];
+}
+
+- (ASCellNode *)collectionNode:(ASCollectionNode *)collectionNode nodeForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
+{
+  if ([kind isEqualToString:UICollectionElementKindSectionHeader] && indexPath.section == 0) {
+    return [[BlurbNode alloc] init];
+  } else if ([kind isEqualToString:UICollectionElementKindSectionFooter] && indexPath.section == 0) {
+    return [[LoadingNode alloc] init];
+  }
+  return nil;
+}
+
+- (ASSizeRange)collectionNode:(ASCollectionNode *)collectionNode constrainedSizeForItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  CGFloat collectionViewWidth = CGRectGetWidth(self.view.frame) - 2 * kHorizontalSectionPadding;
+  CGFloat oneItemWidth = [ItemNode preferredViewSize].width;
+  NSInteger numColumns = floor(collectionViewWidth / oneItemWidth);
+  // Number of columns should be at least 1
+  numColumns = MAX(1, numColumns);
+  
+  CGFloat totalSpaceBetweenColumns = (numColumns - 1) * kHorizontalSectionPadding;
+  CGFloat itemWidth = ((collectionViewWidth - totalSpaceBetweenColumns) / numColumns);
+  CGSize itemSize = [ItemNode sizeForWidth:itemWidth];
+  return ASSizeRangeMake(itemSize, itemSize);
+}
+
+- (NSInteger)collectionNode:(ASCollectionNode *)collectionNode numberOfItemsInSection:(NSInteger)section
+{
+  return [_data count];
+}
+
+- (NSInteger)numberOfSectionsInCollectionNode:(ASCollectionNode *)collectionNode
+{
+  return 1;
+}
+
+- (void)collectionNode:(ASCollectionNode *)collectionNode willBeginBatchFetchWithContext:(ASBatchContext *)context
+{
+  [self fetchMoreCatsWithCompletion:^(BOOL finished){
+    [context completeBatchFetching:YES];
+  }];
+}
+
+#pragma mark - ASCollectionDelegateFlowLayout
+
+- (ASSizeRange)collectionNode:(ASCollectionNode *)collectionNode sizeRangeForHeaderInSection:(NSInteger)section
+{
+  if (section == 0) {
+    return ASSizeRangeUnconstrained;
+  } else {
+    return ASSizeRangeZero;
+  }
+}
+
+- (ASSizeRange)collectionNode:(ASCollectionNode *)collectionNode sizeRangeForFooterInSection:(NSInteger)section
+{
+  if (section == 0) {
+    return ASSizeRangeUnconstrained;
+  } else {
+    return ASSizeRangeZero;
+  }
+}
+
+@end