自定义不规则ControllerCell、CollectionV

CollectionViewFlowLayout

@implementationTagCollectionViewFlowLayout

- (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect

{

NSArray*attributesList = [[NSArrayalloc]initWithArray:[superlayoutAttributesForElementsInRect:rect]copyItems:YES];

if(attributesList.firstObject!=nil) {//首个cell的Frame重置

UICollectionViewLayoutAttributes*currentLayoutAttributes = attributesList.firstObject;

if([selfcollectionViewLayoutAttributesIsCell:currentLayoutAttributes]) {

CGRectframe = currentLayoutAttributes.frame;

frame.origin.x=self.sectionInset.left;

currentLayoutAttributes.frame= frame;

}

}

for(NSUIntegeri =1; i < [attributesListcount]; i++) {

UICollectionViewLayoutAttributes*currentLayoutAttributes = attributesList[i];

if(![selfcollectionViewLayoutAttributesIsCell:currentLayoutAttributes]) {//判断是不是cell有可能是区头区尾

continue;

}

UICollectionViewLayoutAttributes*prevLayoutAttributes = attributesList[i -1];

NSIntegerorigin =CGRectGetMaxX(prevLayoutAttributes.frame);

NSIntegerprevLayoutY =CGRectGetMinY(prevLayoutAttributes.frame);

NSIntegercurrentCellY =CGRectGetMinY(currentLayoutAttributes.frame);

//判断上一个cell的最大x值+间距+当前cell的宽是否小于显示视图减去左右边距&&上一个cell和当前cell必须是同一个section

CGFloatcurrentCellMaxX = origin +self.minimumInteritemSpacing+ currentLayoutAttributes.frame.size.width;

CGFloatcontentWidth =self.collectionViewContentSize.width-self.sectionInset.left-self.sectionInset.right;

if(currentCellMaxX < contentWidth &&

prevLayoutAttributes.indexPath.section== currentLayoutAttributes.indexPath.section) {//如果小于并且是同一个区则当前cell给予换行

CGRectframe = currentLayoutAttributes.frame;

frame.origin.x= origin +self.minimumInteritemSpacing;

currentLayoutAttributes.frame= frame;

}

elseif(prevLayoutY != currentCellY) {

CGRectframe = currentLayoutAttributes.frame;

frame.origin.x=self.sectionInset.left;

currentLayoutAttributes.frame= frame;

}

}

returnattributesList;

}

- (BOOL)collectionViewLayoutAttributesIsCell:(UICollectionViewLayoutAttributes*)attributes

{

if(attributes.representedElementKind==UICollectionElementKindSectionHeader

|| attributes.representedElementKind==UICollectionElementKindSectionFooter) {

returnNO;

}

returnYES;

}

- (BOOL)shouldInvalidateLayoutForBoundsChange:(CGRect)newBounds

{

returnYES;

}

@end