无法监听到滚动到第几 section 值 about zlcollectionview

[czl0325]

- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
    NSInteger currentIndex = 0;
    ZLCollectionViewVerticalLayout* layout = (ZLCollectionViewVerticalLayout*)self.collectionViewLabel.collectionViewLayout;
    NSMutableArray* arr = [NSMutableArray new];
    [arr addObject:@"0"];
    [arr addObjectsFromArray:layout.collectionHeightsArray];
    for (NSInteger i = 0; i < arr.count-1; i++) {
        CGFloat height1 = [arr[i] floatValue];
        CGFloat height2 = [arr[i+1] floatValue];
        if (scrollView.contentOffset.y >= height1 && scrollView.contentOffset.y < height2) {
            currentIndex = i;
            break;
        }
    }
    NSLog(@"当前所在section=%zd", currentIndex);
}