ios – 具有动态高度的UICollectionView单元格之间的空间不会相同

我有类似的问题 like this

我在运行时生成视图的高度.这是我的代码

@interface CollectionViewController ()
{
    NSMutableArray *arrMain;
}
@property(nonatomic,strong) NSMutableArray *arrMain;
@end

@implementation CollectionViewController
@synthesize arrMain,- (void)viewDidLoad
{
    [super viewDidLoad];

    [cView registerNib:[UINib nibWithNibName:@"CViewCell" bundle:nil] forCellWithReuseIdentifier:kCellID];

    CViewFlowLayout *fl = [[CViewFlowLayout alloc] init];
    self.cView.collectionViewLayout = fl;

    Nsstring *strjson = MY FUNCTION WHICH RETURNS JSON STRING;
    SBJSON *parser = [[SBJSON alloc] init];

    self.arrMain = [[NSMutableArray alloc] init];
    self.arrMain = [parser objectWithString:strjson error:nil];
    for (int i=0; i<[self.arrMain count]; i++) {
        NSDictionary *dic = [self.arrMain objectAtIndex:i];
        [self setTags:[[UIView alloc] init] selDictionary:dic];  // This function generates height and save it to the dictionary
    }
    [cView reloadData];
}

- (NSInteger)collectionView:(UICollectionView *)view numberOfItemsInSection:(NSInteger)section;
{
    return [self.arrMain count];
}
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeforItemAtIndexPath:(NSIndexPath *)indexPath
{

    NSDictionary *dic = [self.arrMain objectAtIndex:indexPath.row];
    return CGSizeMake(236,40+[[dic valueForKey:@"TAGS_HEIGHT"] intValue]);
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)cv cellForItemAtIndexPath:(NSIndexPath *)indexPath;
{

    CViewCell *cell =(CViewCell *) [cv dequeueReusableCellWithReuseIdentifier:kCellID forIndexPath:indexPath];
    NSDictionary *dic = [self.arrMain objectAtIndex:indexPath.row];
    if ([cell viewWithTag:11]){
        [[cell viewWithTag:11] release];
        [[cell viewWithTag:11] removeFromSuperview];
    }
    UIView *viewTags = [[UIView alloc] init];
    [viewTags setTag:11];
    [viewTags setBackgroundColor:[UIColor lightGrayColor]];
    [self setTags:viewTags selDictionary:dic];
    [viewTags setFrame:CGRectMake(5,10,CONTENT_WIDTH,[[dic valueForKey:@"TAGS_HEIGHT"] floatValue])];
    [cell.contentView addSubview:viewTags];

    return cell;
}

我试过上面的链接解决方案,但它不适用于我.
这是我的输出的图像.

我需要的间距是相同的.
有人有解决这个问题的人吗？

这是UICOllectionView的错误吗？因为我在this article也发现了这个问题.

解决方法

我有一个这样的问题的一般解决方案：

- (void)viewDidLoad
{
    [super viewDidLoad];

    [cView registerNib:[UINib nibWithNibName:@"CViewCell" bundle:nil] forCellWithReuseIdentifier:kCellID];

    CViewFlowLayout *fl = [[CViewFlowLayout alloc] init];
    fl.minimumInteritemSpacing = 10;
    fl.scrollDirection = UICollectionViewScrollDirectionVertical;
    self.cView.collectionViewLayout = fl;

    Nsstring *strjson = MY FUNCTION WHICH RETURNS JSON STRING;
    SBJSON *parser = [[SBJSON alloc] init];

    self.arrMain = [[NSMutableArray alloc] init];
    self.arrMain = [parser objectWithString:strjson error:nil];
    for (int i=0; i<[self.arrMain count]; i++) {
    NSDictionary *dic = [self.arrMain objectAtIndex:i];
    [self setTags:[[UIView alloc] init] selDictionary:dic];  // This function generates height and save it to the dictionary
}
    [cView reloadData];

}

然后,更新CViewFlowLayout.m中的代码,它是UICollectionViewFlowLayout的一个子类.

这是代码：

#define numColumns 3
@implementation CViewFlowLayout
@synthesize numOfColumnsTodisplay;
- (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect
{
    NSArray* attributesToReturn = [super layoutAttributesForElementsInRect:rect];
    for (UICollectionViewLayoutAttributes* attributes in attributesToReturn)
    {
        if (nil == attributes.representedElementKind)
        {
            NSIndexPath* indexPath = attributes.indexPath;
            attributes.frame = [self layoutAttributesForItemAtIndexPath:indexPath].frame;
        }
    }
    return attributesToReturn;
}

- (UICollectionViewLayoutAttributes *)layoutAttributesForItemAtIndexPath:(NSIndexPath *)indexPath
{
    UICollectionViewLayoutAttributes* currentItemAttributes = [super layoutAttributesForItemAtIndexPath:indexPath];

    if (indexPath.item < numColumns){
        CGRect f = currentItemAttributes.frame;
        f.origin.y = 0;
        currentItemAttributes.frame = f;
        return currentItemAttributes;
    }
    NSIndexPath* ipPrev = [NSIndexPath indexPathForItem:indexPath.item-numColumns inSection:indexPath.section];
    CGRect fPrev = [self layoutAttributesForItemAtIndexPath:ipPrev].frame;
    CGFloat YPointNew = fPrev.origin.y + fPrev.size.height + 10;
    CGRect f = currentItemAttributes.frame;
    f.origin.y = YPointNew;
    currentItemAttributes.frame = f;
    return currentItemAttributes;
}

此解决方案仅适用于垂直滚动.如果要显示更多或更少的列,只需更改numColumns.

原文地址：https://www.jb51.cc/iOS/330522.html