How do you set the duration for UICollectionView Animations?

Question

I have a custom flow layout which is adjusting the attributes for cells when they are being inserted and deleted from the CollectionView with the following two functions, bu

Answer 1

change CALayer's speed

@implementation Cell
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
    self.layer.speed =0.2;//default speed  is 1
}
return self;
}