I dragged the UICollectionView in the storyboard , The UICollectionViewCell size then changed to 0,0,0,0.
The height of the UICollectionView is 0,64,375,60.
The height of CollectionView cell is , with deducting top spacing(5) and bottom spacing(5). i.e Size is (55,55)
The scroll direction is horizontal.
Don't know why I don't see the cell.
My Further findings , I found if the CollectionView is outside the View(green border), then it shows up fine. But as soon as I move inside that view the UICollectionViewCell disappears.