@class NSMutableDictionary, NSDictionary, _UIFlowLayoutInfo, _UIUpdateVisibleCellsContext;
@protocol _UICollectionViewUpdateTranslating;

@interface UICollectionViewFlowLayout : UICollectionViewLayout {
    struct { unsigned char delegateSizeForItem : 1; unsigned char delegateReferenceSizeForHeader : 1; unsigned char delegateReferenceSizeForFooter : 1; unsigned char delegateInsetForSection : 1; unsigned char delegateInteritemSpacingForSection : 1; unsigned char delegateLineSpacingForSection : 1; unsigned char delegateAlignmentOptions : 1; unsigned char layoutDataIsValid : 1; unsigned char delegateInfoIsValid : 1; unsigned char roundsToScreenScale : 1; unsigned char delegateSizesForSection : 1; unsigned char sectionHeadersFloat : 1; unsigned char sectionFootersFloat : 1; unsigned char headerFollowsSectionMargins : 1; unsigned char footerFollowsSectionMargins : 1; unsigned char fetchingItemsInfoForRect : 1; unsigned char isInUpdateVisibleCellsPass : 1; } _gridLayoutFlags;
    _UIFlowLayoutInfo *_data;
    struct CGSize { double width; double height; } _currentLayoutSize;
    NSMutableDictionary *_insertedItemsAttributesDict;
    NSMutableDictionary *_insertedSectionHeadersAttributesDict;
    NSMutableDictionary *_insertedSectionFootersAttributesDict;
    NSMutableDictionary *_deletedItemsAttributesDict;
    NSMutableDictionary *_deletedSectionHeadersAttributesDict;
    NSMutableDictionary *_deletedSectionFootersAttributesDict;
    long long _scrollDirection;
    NSDictionary *_rowAlignmentsOptionsDictionary;
    struct CGPoint { double x; double y; } _contentOffsetAdjustment;
    struct CGSize { double width; double height; } _contentSizeAdjustment;
    NSMutableDictionary *_cachedItemAttributes;
    NSMutableDictionary *_cachedItemFrames;
    _UIUpdateVisibleCellsContext *_updateVisibleCellsContext;
    id<_UICollectionViewUpdateTranslating> _currentUpdateTranslator;
}

@property (readonly, nonatomic, getter=_estimatesSizes) BOOL estimatesSizes;
@property (nonatomic) double minimumLineSpacing;
@property (nonatomic) double minimumInteritemSpacing;
@property (nonatomic) struct CGSize { double width; double height; } itemSize;
@property (nonatomic) struct CGSize { double width; double height; } estimatedItemSize;
@property (nonatomic) long long scrollDirection;
@property (nonatomic) struct CGSize { double width; double height; } headerReferenceSize;
@property (nonatomic) struct CGSize { double width; double height; } footerReferenceSize;
@property (nonatomic) struct UIEdgeInsets { double top; double left; double bottom; double right; } sectionInset;
@property (nonatomic) long long sectionInsetReference;
@property (nonatomic) BOOL sectionHeadersPinToVisibleBounds;
@property (nonatomic) BOOL sectionFootersPinToVisibleBounds;

+ (Class)invalidationContextClass;

- (BOOL)_shouldInvalidateLayoutForUpdatedLayoutMargins:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a0 fromOldMargins:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a1;
- (id)_invalidationContextForUpdatedLayoutMargins:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a0;
- (BOOL)_shouldInvalidateLayoutForOldInsets:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a0 newInsets:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a1;
- (struct CGSize { double x0; double x1; })collectionViewContentSize;
- (void)_willPerformUpdateVisibleCellsPass;
- (BOOL)_shouldInvalidateLayoutForUpdatedSafeAreaInsets:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a0 fromOldInsets:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a1;
- (BOOL)shouldInvalidateLayoutForBoundsChange:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (id)invalidationContextForBoundsChange:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (unsigned long long)_layoutAxis;
- (BOOL)_cellsShouldConferWithAutolayoutEngineForSizingInfo;
- (void)invalidateLayoutWithContext:(id)a0;
- (void)prepareLayout;
- (id)invalidationContextForPreferredLayoutAttributes:(id)a0 withOriginalAttributes:(id)a1;
- (id)layoutAttributesForSupplementaryViewOfKind:(id)a0 atIndexPath:(id)a1;
- (void)_prepareForCollectionViewUpdates:(id)a0 withDataSourceTranslator:(id)a1;
- (BOOL)shouldInvalidateLayoutForPreferredLayoutAttributes:(id)a0 withOriginalAttributes:(id)a1;
- (id)layoutAttributesForElementsInRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (void)_didPerformUpdateVisibleCellsPassWithLayoutOffset:(struct CGPoint { double x0; double x1; })a0;
- (id)init;
- (void)_setCollectionView:(id)a0;
- (id)layoutAttributesForItemAtIndexPath:(id)a0;
- (void)_finalizeCollectionViewUpdate:(id)a0;
- (void)encodeWithCoder:(id)a0;
- (void).cxx_destruct;
- (id)initWithCoder:(id)a0;
- (BOOL)_shouldScrollToContentBeginningInRightToLeft;
- (id)indexesForSectionHeadersInRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (long long)_sectionArrayIndexForIndexPath:(id)a0;
- (id)indexesForSectionFootersInRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (struct UIEdgeInsets { double x0; double x1; double x2; double x3; })_adjustedSectionInsetForSectionInset:(struct UIEdgeInsets { double x0; double x1; double x2; double x3; })a0 forAxis:(unsigned long long)a1;
- (BOOL)_boundsAndInsetsAreValidForReferenceDimension;
- (void)_calculateAttributesForRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (struct CGPoint { double x0; double x1; })_contentOffsetForScrollingToSection:(long long)a0;
- (double)_dimensionFromCollectionView;
- (struct CGSize { double x0; double x1; })_effectiveEstimatedItemSize;
- (id)_existingLayoutAttributesForItemAtIndexPath:(id)a0;
- (id)_fetchAndCacheNewLayoutAttributesForCellWithIndexPath:(id)a0 frame:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a1;
- (void)_fetchItemsInfoForRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (struct UIEdgeInsets { double x0; double x1; double x2; double x3; })_focusFastScrollingIndexBarInsets;
- (BOOL)_footerFollowsSectionMargins;
- (struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })_frameForFooterInSection:(long long)a0 usingData:(id)a1;
- (struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })_frameForHeaderInSection:(long long)a0 usingData:(id)a1;
- (struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })_frameForItem:(long long)a0 inSection:(long long)a1 usingData:(id)a2;
- (void)_getSizingInfosWithExistingSizingDictionary:(id)a0;
- (BOOL)_headerFollowsSectionMargins;
- (void)_invalidateButKeepAllInfo;
- (void)_invalidateButKeepDelegateInfo;
- (id)_layoutAttributesForItemsInRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0;
- (void)_resetCachedItems;
- (BOOL)_roundsToScreenScale;
- (id)_rowAlignmentOptions;
- (void)_setFooterFollowsSectionMargins:(BOOL)a0;
- (void)_setHeaderFollowsSectionMargins:(BOOL)a0;
- (void)_setNeedsLayoutComputationWithoutInvalidation;
- (void)_setRoundsToScreenScale:(BOOL)a0;
- (void)_setRowAlignmentsOptions:(id)a0;
- (void)_updateCollectionViewScrollableAxis;
- (void)_updateContentSizeScrollingDimensionWithDelta:(double)a0;
- (void)_updateDelegateFlags;
- (void)_updateItemsLayoutForRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0 allowsPartialUpdate:(BOOL)a1;
- (long long)developmentLayoutDirection;
- (id)finalLayoutAttributesForDeletedItemAtIndexPath:(id)a0;
- (id)finalLayoutAttributesForFooterInDeletedSection:(long long)a0;
- (id)finalLayoutAttributesForHeaderInDeletedSection:(long long)a0;
- (id)indexPathForItemAtPoint:(struct CGPoint { double x0; double x1; })a0;
- (id)indexesForSectionFootersInRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0 usingData:(id)a1;
- (id)indexesForSectionHeadersInRect:(struct CGRect { struct CGPoint { double x0; double x1; } x0; struct CGSize { double x0; double x1; } x1; })a0 usingData:(id)a1;
- (id)initialLayoutAttributesForFooterInInsertedSection:(long long)a0;
- (id)initialLayoutAttributesForHeaderInInsertedSection:(long long)a0;
- (id)initialLayoutAttributesForInsertedItemAtIndexPath:(id)a0;
- (id)layoutAttributesForFooterInSection:(long long)a0;
- (id)layoutAttributesForFooterInSection:(long long)a0 usingData:(id)a1;
- (id)layoutAttributesForHeaderInSection:(long long)a0;
- (id)layoutAttributesForHeaderInSection:(long long)a0 usingData:(id)a1;
- (id)layoutAttributesForItemAtIndexPath:(id)a0 usingData:(id)a1;
- (struct CGSize { double x0; double x1; })synchronizeLayout;

@end