Question

目前我的UICollectionView中有一个标题单元格。当我尝试滚动UICollectionView时，标题单元格将与UICollectionView列表一起滚动。我可以知道如何将标题单元格棒设置在顶部吗？请帮忙。谢谢。

我目前的结果： -

我的预期结果： -

以下是我的ViewController中标题单元格的示例代码： -

- (UICollectionView *)collectionView
{
    if (!_collectionView) {
        DCHoverFlowLayout *layout = [DCHoverFlowLayout new];
        _collectionView = [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:layout];
        _collectionView.frame = CGRectMake(0, DCTopNavH, ScreenW, ScreenH - DCTopNavH);

        _collectionView.showsVerticalScrollIndicator = NO;
        _collectionView.delegate = self;
        _collectionView.dataSource = self;

        [_collectionView registerClass:[Product_HeadView class] forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:Product_HeadViewID];

    }
    return _collectionView;
}



- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath {

    UICollectionReusableView *reusableview = nil;
    if (kind == UICollectionElementKindSectionHeader){

        Product_HeadView *headerView = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:Product_HeadViewID forIndexPath:indexPath];
        WEAKSELF

  };
        reusableview = headerView;
        return cell;
    }

-(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{

    _lastContentOffset = scrollView.contentOffset.y;

}
-(void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView
{

    if(scrollView.contentOffset.y > _lastContentOffset){
        [self.navigationController setNavigationBarHidden:YES animated:YES];
        self.collectionView.frame = CGRectMake(0, 20, ScreenW, ScreenH - 20);

        self.view.backgroundColor = [UIColor whiteColor];
    }else{
        [self.navigationController setNavigationBarHidden:NO animated:YES];
        self.collectionView.frame = CGRectMake(0, DCTopNavH, ScreenW, ScreenH - DCTopNavH);

        self.view.backgroundColor = ThemeBackgroundColor;
    }
}

#pragma mark - <UIScrollViewDelegate>
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
    //Detect Button Visible
    _backTopButton.hidden = (scrollView.contentOffset.y > ScreenH) ? NO : YES;


    WEAKSELF
    [UIView animateWithDuration:0.25 animations:^{
        __strong typeof(weakSelf)strongSelf = weakSelf;
        strongSelf.footprintButton.dc_y = (strongSelf.backTopButton.hidden == YES) ? ScreenH - 60 : ScreenH - 110;
    }];

}

更新： -

应用Ted的代码后，结果就是这里，应用程序会崩溃。

Answer 1

一种选择是使用UIViewController而不是UICollectionViewController。添加视图以用作视图控制器的标题，然后在标题视图下添加集合视图。

这样，标题不是集合视图的一部分，它根本不会滚动。

Answer 2

使用viewForSupplementaryElementOfKind方法。添加以下行：

UICollectionViewFlowLayout *layout = collectionView.collectionViewLayout;
layout.sectionHeadersPinToVisibleBounds = YES;

Answer 3

tedd的答案的快速版本：

let layout = collectionView.collectionViewLayout as! UICollectionViewFlowLayout
layout.sectionHeadersPinToVisibleBounds = true

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