// // CGXVerticalMenuRoundFlowLayout.m // CGXVerticalMenuView-OC // // Created by CGX on 2018/05/01. // Copyright © 2019 CGX. All rights reserved. // #import "CGXVerticalMenuRoundFlowLayout.h" #import "CGXVerticalMenuRoundFlowLayoutUtils.h" static NSString *const CGXVerticalMenuRoundFlowLayoutRoundSection = @"com.CGXVerticalMenuRoundFlowLayoutRoundSection"; @interface CGXVerticalMenuRoundFlowLayout () @property (nonatomic, strong) NSMutableArray *decorationViewAttrs; @property (nonatomic, strong,readwrite) NSArray *sectionHeaderAttributes; @end @implementation CGXVerticalMenuRoundFlowLayout - (instancetype)init{ self = [super init]; if (self) { self.isRoundEnabled = YES; } return self; } - (void)awakeFromNib{ [super awakeFromNib]; _isRoundEnabled = YES; } - (void)prepareLayout{ [super prepareLayout]; if (!self.isRoundEnabled) { return; } NSInteger sections = [self.collectionView numberOfSections]; id delegate = (id )self.collectionView.delegate; // id delegate = self.collectionView.delegate; //检测是否实现了背景样式模块代理 if ([delegate respondsToSelector:@selector(collectionView:configModelForSectionAtIndex:)]) { }else{ return ; } //1.初始化 [self registerClass:[CGXVerticalMenuRoundReusableView class] forDecorationViewOfKind:CGXVerticalMenuRoundFlowLayoutRoundSection]; [self.decorationViewAttrs removeAllObjects]; for (NSInteger section = 0; section < sections; section++) { NSInteger numberOfItems = [self.collectionView numberOfItemsInSection:section]; if (numberOfItems > 0) { UICollectionViewLayoutAttributes *firstAttr = [self layoutAttributesForItemAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:section]]; CGRect firstFrame = firstAttr.frame; //headerView UICollectionViewLayoutAttributes *headerAttr = [self layoutAttributesForSupplementaryViewOfKind:UICollectionElementKindSectionHeader atIndexPath:[NSIndexPath indexPathForRow:0 inSection:section]]; //footerView UICollectionViewLayoutAttributes *footerAttr = [self layoutAttributesForSupplementaryViewOfKind:UICollectionElementKindSectionFooter atIndexPath:[NSIndexPath indexPathForRow:0 inSection:section]]; // 最后一个item UICollectionViewLayoutAttributes *lastAttr = [self layoutAttributesForItemAtIndexPath:[NSIndexPath indexPathForRow:(numberOfItems - 1) inSection:section]]; CGRect lastFrame = lastAttr.frame; BOOL isHeaderAttr = (headerAttr && (headerAttr.frame.size.width != 0 && headerAttr.frame.size.height != 0)); BOOL isFooterAttr = (footerAttr && (footerAttr.frame.size.width != 0 && footerAttr.frame.size.height != 0)); //判断是否计算headerview BOOL isCalculateHeaderView = [self isCalculateHeaderViewSection:section] && isHeaderAttr; //判断是否计算footerView BOOL isCalculateFooterView = [self isCalculateFooterViewSection:section] && isFooterAttr; firstFrame = [self calculateDefaultFrameWithFirstHeader:isCalculateHeaderView Section:section NumberOfItems:numberOfItems IsOpen:self.isCalculateOpenIrregularCell]; lastFrame = [self calculateDefaultFrameWithFirstFooter:isCalculateFooterView Section:section NumberOfItems:numberOfItems IsOpen:self.isCalculateOpenIrregularCell]; //获取sectionInset UIEdgeInsets sectionInset = [CGXVerticalMenuRoundFlowLayoutUtils evaluatedSectionInsetForItemWithCollectionLayout:self atIndex:section]; CGRect sectionFrame = CGRectUnion(firstFrame, lastFrame); if (!isCalculateHeaderView && !isCalculateFooterView) { //都没有headerView&footerView sectionFrame = [self calculateDefaultFrameWithSectionFrame:sectionFrame sectionInset:sectionInset]; }else{ if (isCalculateHeaderView && !isCalculateFooterView) { //判断是否有headerview if (isHeaderAttr) { //判断包含headerview, top位置已经计算在内，不需要补偏移 sectionFrame.size.height += sectionInset.bottom; }else{ sectionFrame = [self calculateDefaultFrameWithSectionFrame:sectionFrame sectionInset:sectionInset]; } }else if (!isCalculateHeaderView && isCalculateFooterView) { if (isFooterAttr) { //判断包含footerView, bottom位置已经计算在内，不需要补偏移 //(需要补充y偏移) sectionFrame.origin.y -= sectionInset.top; sectionFrame.size.width = self.collectionView.frame.size.width; sectionFrame.size.height += sectionInset.top; }else{ sectionFrame = [self calculateDefaultFrameWithSectionFrame:sectionFrame sectionInset:sectionInset]; } }else{ if (isHeaderAttr && isFooterAttr) { //都有headerview和footerview就不用计算了 }else{ sectionFrame = [self calculateDefaultFrameWithSectionFrame:sectionFrame sectionInset:sectionInset]; } } } UIEdgeInsets userCustomSectionInset = UIEdgeInsetsMake(0, 0, 0, 0); if ([delegate respondsToSelector:@selector(collectionView:borderEdgeInsertsForSectionAtIndex:)]) { //检测是否实现了该方法，进行赋值 userCustomSectionInset = [delegate collectionView:self.collectionView borderEdgeInsertsForSectionAtIndex:section]; } sectionFrame.origin.x += userCustomSectionInset.left; sectionFrame.origin.y += userCustomSectionInset.top; if (self.scrollDirection == UICollectionViewScrollDirectionHorizontal) { sectionFrame.size.width -= (userCustomSectionInset.left + userCustomSectionInset.right); sectionFrame.size.height -= (userCustomSectionInset.top + userCustomSectionInset.bottom); }else{ sectionFrame.size.width -= (userCustomSectionInset.left + userCustomSectionInset.right); sectionFrame.size.height -= (userCustomSectionInset.top + userCustomSectionInset.bottom); } //2. 定义 CGXVerticalMenuRoundLayoutAttributes *attr = [CGXVerticalMenuRoundLayoutAttributes layoutAttributesForDecorationViewOfKind:CGXVerticalMenuRoundFlowLayoutRoundSection withIndexPath:[NSIndexPath indexPathForRow:0 inSection:section]]; attr.frame = sectionFrame; attr.zIndex = -1; attr.borderEdgeInsets = userCustomSectionInset; if ([delegate respondsToSelector:@selector(collectionView:configModelForSectionAtIndex:)]) { attr.myConfigModel = [delegate collectionView:self.collectionView configModelForSectionAtIndex:section]; } [self.decorationViewAttrs addObject:attr]; }else{ continue ; } } if (sections>0) { if (self.sectionHeaderAttributes == nil) { //获取到所有的sectionHeaderAtrributes，用于后续的点击，滚动到指定contentOffset.y使用 NSMutableArray *attributes = [NSMutableArray array]; UICollectionViewLayoutAttributes *lastHeaderAttri = nil; for (int i = 0; i < sections; i++) { UICollectionViewLayoutAttributes *attri = [self.collectionView.collectionViewLayout layoutAttributesForSupplementaryViewOfKind:UICollectionElementKindSectionHeader atIndexPath:[NSIndexPath indexPathForItem:0 inSection:i]]; if (attri) { [attributes addObject:attri]; } if (i == sections - 1) { lastHeaderAttri = attri; } } if (attributes.count == 0) { return; } self.sectionHeaderAttributes = attributes; // NSInteger rowCount = [self.collectionView numberOfItemsInSection:sections-1]; // //如果最后一个section条目太少了，会导致滚动最底部，但是却不能触发categoryView选中最后一个item。而且点击最后一个滚动的contentOffset.y也不好弄。所以添加contentInset，让最后一个section滚到最下面能显示完整个屏幕。 // UICollectionViewLayoutAttributes *lastCellAttri = [self.collectionView.collectionViewLayout layoutAttributesForItemAtIndexPath:[NSIndexPath indexPathForItem:rowCount inSection:sections-1]]; // CGFloat lastSectionHeight = CGRectGetMaxY(lastCellAttri.frame) - CGRectGetMinY(lastHeaderAttri.frame); // CGFloat value = self.collectionView.bounds.size.height - lastSectionHeight; // if (value > 0) { // self.collectionView.contentInset = UIEdgeInsetsMake(0, 0, value+20, 0); // } } } } - (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect{ NSMutableArray * attrs = [[super layoutAttributesForElementsInRect:rect] mutableCopy]; for (UICollectionViewLayoutAttributes *attr in self.decorationViewAttrs) { [attrs addObject:attr]; } [self layoutHeaderFooterAttributesForElementsInRect:rect attributes:attrs]; return attrs; } //return YES;表示一旦滑动就实时调用上面这个layoutAttributesForElementsInRect:方法 - (BOOL)shouldInvalidateLayoutForBoundsChange:(CGRect)newBound { return YES; } - (void)layoutHeaderFooterAttributesForElementsInRect:(CGRect)rect attributes:(NSMutableArray *)superAttributes { NSMutableIndexSet *noneHeaderSections = [NSMutableIndexSet indexSet]; for (UICollectionViewLayoutAttributes *attributes in superAttributes) { if (attributes.representedElementCategory == UICollectionElementCategoryCell) { [noneHeaderSections addIndex:attributes.indexPath.section]; } } for (UICollectionViewLayoutAttributes *attributes in superAttributes) { if ([attributes.representedElementKind isEqualToString:UICollectionElementKindSectionHeader]) { [noneHeaderSections removeIndex:attributes.indexPath.section]; } } [noneHeaderSections enumerateIndexesUsingBlock:^(NSUInteger idx, BOOL *stop){ NSIndexPath *indexPath = [NSIndexPath indexPathForItem:0 inSection:idx]; UICollectionViewLayoutAttributes *attributes = [self layoutAttributesForSupplementaryViewOfKind:UICollectionElementKindSectionHeader atIndexPath:indexPath]; if (attributes) { [superAttributes addObject:attributes]; } }]; id delegate = (id )self.collectionView.delegate; for (UICollectionViewLayoutAttributes *attributes in superAttributes) { BOOL sectionHeaderViewHovering = NO; if (delegate && [delegate respondsToSelector:@selector(collectionView:sectionHeadersPinAtSection:)]) { sectionHeaderViewHovering = [delegate collectionView:self.collectionView sectionHeadersPinAtSection:attributes.indexPath.section]; } CGFloat sectionHeaderViewHoveringTopEdging = 0; if (delegate && [delegate respondsToSelector:@selector(collectionView:sectionHeadersPinTopSpaceAtSection:)]) { sectionHeaderViewHoveringTopEdging = [delegate collectionView:self.collectionView sectionHeadersPinTopSpaceAtSection:attributes.indexPath.section]; } UIEdgeInsets sectionInset = [self gx_insetForSectionAtIndex:attributes.indexPath.section]; if (sectionHeaderViewHovering) { if ([attributes.representedElementKind isEqualToString:UICollectionElementKindSectionHeader]){ NSInteger numberOfItemsInSection = [self.collectionView numberOfItemsInSection:attributes.indexPath.section]; NSIndexPath *firstItemIndexPath = [NSIndexPath indexPathForItem:0 inSection:attributes.indexPath.section]; NSIndexPath *lastItemIndexPath = [NSIndexPath indexPathForItem:MAX(0, numberOfItemsInSection-1) inSection:attributes.indexPath.section]; UICollectionViewLayoutAttributes *firstItemAttributes, *lastItemAttributes; if (numberOfItemsInSection>0){ firstItemAttributes = [self layoutAttributesForItemAtIndexPath:firstItemIndexPath]; lastItemAttributes = [self layoutAttributesForItemAtIndexPath:lastItemIndexPath]; }else{ firstItemAttributes = [UICollectionViewLayoutAttributes new]; CGFloat y = CGRectGetMaxY(attributes.frame)+self.sectionInset.top; firstItemAttributes.frame = CGRectMake(0, y, 0, 0); lastItemAttributes = firstItemAttributes; } CGRect rect = attributes.frame; CGFloat offset = self.collectionView.contentOffset.y + sectionHeaderViewHoveringTopEdging; CGFloat headerY = firstItemAttributes.frame.origin.y - rect.size.height - sectionInset.top; CGFloat maxY = MAX(offset,headerY); CGFloat headerMissingY = CGRectGetMaxY(lastItemAttributes.frame) + sectionInset.bottom - rect.size.height; rect.origin.y = MIN(maxY,headerMissingY); attributes.frame = rect; attributes.zIndex = 1; } } } } //判断是否计算headerview - (BOOL)isCalculateHeaderViewSection:(NSInteger)section { BOOL isCalculateHeaderView = NO; id delegate = (id )self.collectionView.delegate; if ([delegate respondsToSelector:@selector(collectionView:isCalculateHeaderViewIndex:)]) { isCalculateHeaderView = [delegate collectionView:self.collectionView isCalculateHeaderViewIndex:section]; }else{ isCalculateHeaderView = self.isCalculateHeader; } return isCalculateHeaderView; } //判断是否计算footerView - (BOOL)isCalculateFooterViewSection:(NSInteger)section { BOOL isCalculateFooterView = NO; id delegate = (id )self.collectionView.delegate; if ([delegate respondsToSelector:@selector(collectionView:isCalculateFooterViewIndex:)]) { isCalculateFooterView = [delegate collectionView:self.collectionView isCalculateFooterViewIndex:section]; }else{ isCalculateFooterView = self.isCalculateFooter; } return isCalculateFooterView; } /// 计算默认不包含headerview和footerview的背景大小 /// @param frame frame description /// @param sectionInset sectionInset description - (CGRect)calculateDefaultFrameWithSectionFrame:(CGRect)frame sectionInset:(UIEdgeInsets)sectionInset{ CGRect sectionFrame = frame; sectionFrame.origin.x -= sectionInset.left; sectionFrame.origin.y -= sectionInset.top; if (self.scrollDirection == UICollectionViewScrollDirectionHorizontal) { sectionFrame.size.width += sectionInset.left + sectionInset.right; //减去系统adjustInset的top if (@available(iOS 11.0, *)) { sectionFrame.size.height = self.collectionView.frame.size.height - self.collectionView.adjustedContentInset.top; } else { sectionFrame.size.height = self.collectionView.frame.size.height - fabs(self.collectionView.contentOffset.y)/*适配iOS11以下*/; } }else{ sectionFrame.size.width = self.collectionView.frame.size.width; sectionFrame.size.height += sectionInset.top + sectionInset.bottom; } return sectionFrame; } /// 计算headerview背景大小 /// @param isCalculateHeaderView 是否计算头 /// @param section 分区 /// @param numberOfItems 第几个 /// @param isOpen 是否打开不规则运算 - (CGRect)calculateDefaultFrameWithFirstHeader:(BOOL)isCalculateHeaderView Section:(NSInteger)section NumberOfItems:(NSInteger)numberOfItems IsOpen:(BOOL)isOpen { BOOL isCalculateOpenIrregularCell = isOpen; // 第一个item UICollectionViewLayoutAttributes *firstAttr = [self layoutAttributesForItemAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:section]]; //headerView UICollectionViewLayoutAttributes *headerAttr = [self layoutAttributesForSupplementaryViewOfKind:UICollectionElementKindSectionHeader atIndexPath:[NSIndexPath indexPathForRow:0 inSection:section]]; CGRect firstFrame = firstAttr.frame; if (isCalculateHeaderView) { if (headerAttr && (headerAttr.frame.size.width != 0 && headerAttr.frame.size.height != 0)) { firstFrame = headerAttr.frame; }else{ CGRect rect = firstFrame; if (isCalculateOpenIrregularCell) { rect = [CGXVerticalMenuRoundFlowLayoutUtils calculateIrregularitiesCellByMinTopFrameWithLayout:self section:section numberOfItems:numberOfItems defaultFrame:rect]; } firstFrame = CGRectMake(rect.origin.x, rect.origin.y, self.collectionView.bounds.size.width, rect.size.height); } }else{ //不计算headerview的情况 if (isCalculateOpenIrregularCell) { firstFrame = [CGXVerticalMenuRoundFlowLayoutUtils calculateIrregularitiesCellByMinTopFrameWithLayout:self section:section numberOfItems:numberOfItems defaultFrame:firstFrame]; } } return firstFrame; } /// 计算footerview的背景大小 /// @param isCalculateFooterView 是否计算脚 /// @param section 分区 /// @param numberOfItems 第几个 /// @param isOpen 是否打开不规则运算 - (CGRect)calculateDefaultFrameWithFirstFooter:(BOOL)isCalculateFooterView Section:(NSInteger)section NumberOfItems:(NSInteger)numberOfItems IsOpen:(BOOL)isOpen { BOOL isCalculateOpenIrregularCell = isOpen; // 最后一个item UICollectionViewLayoutAttributes *lastAttr = [self layoutAttributesForItemAtIndexPath:[NSIndexPath indexPathForRow:(numberOfItems - 1) inSection:section]]; //footerView UICollectionViewLayoutAttributes *footerAttr = [self layoutAttributesForSupplementaryViewOfKind:UICollectionElementKindSectionFooter atIndexPath:[NSIndexPath indexPathForRow:0 inSection:section]]; CGRect lastFrame = lastAttr.frame; if (isCalculateFooterView) { if (footerAttr && (footerAttr.frame.size.width != 0 && footerAttr.frame.size.height != 0)) { lastFrame = footerAttr.frame; }else{ CGRect rect = lastFrame; if (isCalculateOpenIrregularCell) { rect = [CGXVerticalMenuRoundFlowLayoutUtils calculateIrregularitiesCellByMaxBottomFrameWithLayout:self section:section numberOfItems:numberOfItems defaultFrame:rect]; } lastFrame = CGRectMake(rect.origin.x, rect.origin.y, self.collectionView.bounds.size.width, rect.size.height); } }else{ //不计算footerView的情况 if (isCalculateOpenIrregularCell) { lastFrame = [CGXVerticalMenuRoundFlowLayoutUtils calculateIrregularitiesCellByMaxBottomFrameWithLayout:self section:section numberOfItems:numberOfItems defaultFrame:lastFrame]; } } return lastFrame; } #pragma mark - other - (NSMutableArray *)decorationViewAttrs{ if (!_decorationViewAttrs) { _decorationViewAttrs = [NSMutableArray array]; } return _decorationViewAttrs; } - (CGFloat)gx_minimumInteritemSpacingForSectionAtIndex:(NSInteger)section { if (self.collectionView.delegate && [self.collectionView.delegate respondsToSelector:@selector(collectionView:layout:minimumInteritemSpacingForSectionAtIndex:)]) { id delegate = (id) self.collectionView.delegate; return [delegate collectionView:self.collectionView layout:self minimumInteritemSpacingForSectionAtIndex:section]; } else { return self.minimumInteritemSpacing; } } - (CGFloat)gx_minimumLineSpacingForSectionAtIndex:(NSInteger)section { if (self.collectionView.delegate && [self.collectionView.delegate respondsToSelector:@selector(collectionView:layout:minimumLineSpacingForSectionAtIndex:)]) { id delegate = (id) self.collectionView.delegate; return [delegate collectionView:self.collectionView layout:self minimumLineSpacingForSectionAtIndex:section]; } else { return self.minimumLineSpacing; } } - (CGSize)gx_referenceSizeForHeaderInSection:(NSInteger)section { CGSize size = CGSizeMake(0, 0); if (self.collectionView.delegate && [self.collectionView.delegate respondsToSelector:@selector(collectionView:layout:referenceSizeForHeaderInSection:)]) { id delegate = (id) self.collectionView.delegate; size = [delegate collectionView:self.collectionView layout:self referenceSizeForHeaderInSection:section]; } else{ size = self.headerReferenceSize; } return size; } - (CGSize)gx_referenceSizeForFooterInSection:(NSInteger)section { CGSize size = CGSizeMake(0, 0); if (self.collectionView.delegate && [self.collectionView.delegate respondsToSelector:@selector(collectionView:layout:referenceSizeForFooterInSection:)]) { id delegate = (id) self.collectionView.delegate; size = [delegate collectionView:self.collectionView layout:self referenceSizeForFooterInSection:section]; } else{ size = self.footerReferenceSize; } return size; } - (UIEdgeInsets)gx_insetForSectionAtIndex:(NSInteger)section { if (self.collectionView.delegate && [self.collectionView.delegate respondsToSelector:@selector(collectionView:layout:insetForSectionAtIndex:)]) { id delegate = (id) self.collectionView.delegate; return [delegate collectionView:self.collectionView layout:self insetForSectionAtIndex:section]; } else { return self.sectionInset; } } - (CGSize)gx_sizeForItemAtIndexPath:(NSIndexPath *)indexPath { if (self.collectionView.delegate && [self.collectionView.delegate respondsToSelector:@selector(collectionView:layout:sizeForItemAtIndexPath:)]) { id delegate = (id) self.collectionView.delegate; return [delegate collectionView:self.collectionView layout:self sizeForItemAtIndexPath:indexPath]; } else { return self.itemSize; } } @end