IOS UICollectionView with floating section header view overlapped

I try to add floating section header view in my collectionView. But after adding in it, I noticed that the fps goes down when I try to scroll it. I check UI Hierarchy, I found that the header view overlapped.

The overlapped header viewClick here to see the pic...

I used a third party lib to add the floating effect of header view, the page of this lib is https://github.com/hytzxd/XDSectionHeaderCollectionView. What I wrote in my .m file is:

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

if ([kind isEqualToString:UICollectionElementKindSectionHeader]) {
    UICollectionReusableView *headerView = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"HeaderView" forIndexPath:indexPath];

    NSString *time = [self.dates objectAtIndex:indexPath.section];

    //    UIBlurEffect *effect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleExtraLight];
    //    UIVisualEffectView *effectView = [[UIVisualEffectView alloc] initWithEffect:effect];
    UIView *effectView = [[UIView alloc] init];
    effectView.frame = headerView.bounds;

    UILabel *timeLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, effectView.bounds.size.width, effectView.bounds.size.height/2)];
    timeLabel.text = time;
    [effectView addSubview:timeLabel];

    UILabel *locationLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, effectView.bounds.size.height/2, effectView.bounds.size.width, effectView.bounds.size.height/2)];
    locationLabel.text = @"获取中...";
    locationLabel.font = [UIFont systemFontOfSize:10];
    [effectView addSubview:locationLabel];

    timeLabel.backgroundColor = [UIColor clearColor];
    timeLabel.layer.masksToBounds = YES;
    locationLabel.backgroundColor = [UIColor clearColor];
    locationLabel.layer.masksToBounds = YES;

    [headerView addSubview:effectView];

    retu headerView;

}
retu nil;

}

I tried to use blur effect view for the first time, I couldn't find any problem, so I changed to a normal UIView.