How to do paging in UICollectionView

Question

I have a Collection View can show about 5 cells at a time, and I want it be paging enabled. But the page stretch out the view's bounds. I want it to show 10 cells a page, and scroll the view to snap to other page. You can see below pic:

My current code is like this:

- (void)setUpCollectionView
{
    UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
    layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;

    self.collectionView = [[UICollectionView alloc] initWithFrame:self.view.frame collectionViewLayout:layout];
    self.collectionView.pagingEnabled = YES;
    self.collectionView.delegate = self;
    self.collectionView.dataSource = self;
    self.collectionView.showsHorizontalScrollIndicator = NO;
    [self.view addSubview:self.collectionView];

    self.collectionView.translatesAutoresizingMaskIntoConstraints = NO;

    self.collectionView.backgroundColor = [UIColor whiteColor];

    UINib *nib = [UINib nibWithNibName:@"CollectionViewCell" bundle:nil];
    [self.collectionView registerNib:nib forCellWithReuseIdentifier:@"Cell"];
}

- (void)updateViewConstraints {
    [super updateViewConstraints];

    NSLayoutConstraint *collectionViewLeftSideConstraint = [NSLayoutConstraint constraintWithItem:self.collectionView attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeLeft multiplier:1.0 constant:0];
    NSLayoutConstraint *collectionViewTopConstraint = [NSLayoutConstraint constraintWithItem:self.collectionView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeTop multiplier:1.0 constant:0];
    NSLayoutConstraint *collectionViewBottomConstraint = [NSLayoutConstraint constraintWithItem:self.collectionView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:self.nextKeyboardButton attribute:NSLayoutAttributeTop multiplier:1.0 constant:0.0];
    NSLayoutConstraint *collectionViewRightSideConstraint = [NSLayoutConstraint constraintWithItem:self.collectionView attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeRight multiplier:1.0 constant:0];

    [self.view addConstraints:@[collectionViewBottomConstraint, collectionViewLeftSideConstraint, collectionViewRightSideConstraint, collectionViewTopConstraint]];
}