UICollectionViewCell remove space with animation while scrolling - ios

Question

I have an issue with UICollectionViewCell design layout. I need to remove space with animation while scrolling between UICollectionView Cell, I have try some delegate method of UICollectionView like -
CollectionView - minimumLineSpacingForSectionAtIndex
CollectionView - minimumInteritemSpacingForSectionAtIndex
UIEdgeInsetsMake(0,0,0,0);
scrollViewDidEndDragging
but unable to up to the mark. here is the code:
- (CGSize)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
CGRect screenRect = [[UIScreen mainScreen] bounds];
CGFloat screenWidth = screenRect.size.width;
float cellWidth = screenWidth / 2.1; //Replace the divisor with the column count requirement. Make sure to have it in float.
CGSize size = CGSizeMake(cellWidth, cellWidth);
return size;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section
{
return 1.0;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section
{
return 1.0;
}
// Layout: Set Edges
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
return UIEdgeInsetsMake(0,0,0,0); // top, left, bottom, right
}
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
UIEdgeInsetsMake(0,0,0,0); // after scroll cell space not remove.
}

Answer 1

I didn't completely understand what you're trying to do, but if you want to change layout attributes of a collection view and animate the change, the best way is calling setLayout:animated:.
So like this -
UICollectionViewFlowLayout *layout = [UICollectionViewFlowLayout alloc] init];
layout.minimumLineSpacing = 1.0;
layout.minimumInteritemSpacing = 1.0;
layout.itemSize = CGSizeMake(cellWidth, cellHeight);
UICollectionView *collectionView = [[UICollectionView alloc] initWithFrame:frame collectionViewLayout:layout]
And then whenever you want to change it, just call the setLayout:animated: method:
UICollectionViewFlowLayout *layout = [UICollectionViewFlowLayout alloc] init];
initialLayout.minimumLineSpacing = 5.0;
initialLayout.minimumInteritemSpacing = 7.0;
layout.itemSize = CGSizeMake(newCellWidth, newCellHeight);
[collectionView setLayout:layout animated:YES];