Swiftgram/Source/Details/ASCollectionViewLayoutInspector.mm
Adlai Holler d0ba092a77
Convert the codebase to Objective-C++ (#1206)
* Convert the codebase to Objective-C++ throughout. One language is better than two.

* Put it back

* Fix linker

* Point explicitly to updated Weaver to unblock build

* Revert "Point explicitly to updated Weaver to unblock build"

This reverts commit fdc25296e8794d4e6e56c35f5fe6da2be3f71dbc.

* Revert "Fix linker"

This reverts commit 7be25f91519b8497ef42de79f115bcfbdb965c39.

* Add in the frameworks

* no message

* Address spec lint warnings

* Fix tvos build

* Put that back

* Address Michael's review

* Add comment to kick CI
2018-11-02 12:04:14 -07:00

77 lines
3.2 KiB
Plaintext

//
// ASCollectionViewLayoutInspector.mm
// 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 <AsyncDisplayKit/ASCollectionViewLayoutInspector.h>
#import <AsyncDisplayKit/ASCollectionView.h>
#import <AsyncDisplayKit/ASCollectionView+Undeprecated.h>
#import <AsyncDisplayKit/ASCollectionNode.h>
#pragma mark - Helper Functions
// Returns a constrained size to let the cells layout itself as far as possible based on the scrollable direction
// of the collection view
ASSizeRange NodeConstrainedSizeForScrollDirection(ASCollectionView *collectionView) {
CGSize maxSize = collectionView.bounds.size;
UIEdgeInsets contentInset = collectionView.contentInset;
if (ASScrollDirectionContainsHorizontalDirection(collectionView.scrollableDirections)) {
maxSize.width = CGFLOAT_MAX;
maxSize.height -= (contentInset.top + contentInset.bottom);
} else {
maxSize.width -= (contentInset.left + contentInset.right);
maxSize.height = CGFLOAT_MAX;
}
return ASSizeRangeMake(CGSizeZero, maxSize);
}
#pragma mark - ASCollectionViewLayoutInspector
@implementation ASCollectionViewLayoutInspector {
struct {
unsigned int implementsConstrainedSizeForNodeAtIndexPathDeprecated:1;
unsigned int implementsConstrainedSizeForNodeAtIndexPath:1;
} _delegateFlags;
}
#pragma mark ASCollectionViewLayoutInspecting
- (void)didChangeCollectionViewDelegate:(id<ASCollectionDelegate>)delegate
{
if (delegate == nil) {
memset(&_delegateFlags, 0, sizeof(_delegateFlags));
} else {
_delegateFlags.implementsConstrainedSizeForNodeAtIndexPathDeprecated = [delegate respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)];
_delegateFlags.implementsConstrainedSizeForNodeAtIndexPath = [delegate respondsToSelector:@selector(collectionNode:constrainedSizeForItemAtIndexPath:)];
}
}
- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath
{
if (_delegateFlags.implementsConstrainedSizeForNodeAtIndexPath) {
return [collectionView.asyncDelegate collectionNode:collectionView.collectionNode constrainedSizeForItemAtIndexPath:indexPath];
} else if (_delegateFlags.implementsConstrainedSizeForNodeAtIndexPathDeprecated) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
return [collectionView.asyncDelegate collectionView:collectionView constrainedSizeForNodeAtIndexPath:indexPath];
#pragma clang diagnostic pop
} else {
// With 2.0 `collectionView:constrainedSizeForNodeAtIndexPath:` was moved to the delegate. Assert if not implemented on the delegate but on the data source
ASDisplayNodeAssert([collectionView.asyncDataSource respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)] == NO, @"collectionView:constrainedSizeForNodeAtIndexPath: was moved from the ASCollectionDataSource to the ASCollectionDelegate.");
}
return NodeConstrainedSizeForScrollDirection(collectionView);
}
- (ASScrollDirection)scrollableDirections
{
return ASScrollDirectionNone;
}
@end