Objectivec 为什么 UICollectionView 的 UICollectionViewCell 没有在用户时突出显示

I have a UICollectionView that is made up of a custom UICollectionViewCell subclass. The cell's are displaying correctly and are responding correctly to user's touches by firing this method:

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath

However, I am of the understanding that when a user touches the cell, it should highlight (in blue) and then the highlight should go away when the user lifts their finger. This is not happening. Any thoughts on why?

Here is some relevant code:

In the UICollectionView's datasource:

@implementation SplitCheckViewCollection

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
    static NSString *cellIdentifier = @"ReceiptCellIdentifier";
    SplitCheckCollectionCell *cell = (SplitCheckCollectionCell *)[collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];
    cell.cellName.text = [NSString stringWithFormat:@"%@%i",@"#",indexPath.row+1];

    return cell;
}

In the UICollectionViewCell's implementation:

@implementation SplitCheckCollectionCell

- (id)initWithFrame:(CGRect)frame {
    self = [super initWithFrame:frame];
    if (self) {
        NSArray *arrayOfViews = [[NSBundle mainBundle] loadNibNamed:@"SplitCheckCollectionCell" owner:self options:nil];

        if ([arrayOfViews count] < 1) {
            return nil;
        }

        if (![[arrayOfViews objectAtIndex:0] isKindOfClass:[UICollectionViewCell class]]) {
            return nil;
        }

        self = [arrayOfViews objectAtIndex:0];    
    }
    return self;
}