iPhone X上的集合视图单元格的布局错误

Question

我有一个视图控制器，其中包含具有以下设置的集合视图：

- (void)viewDidLoad {
    [super viewDidLoad];

    [self createDataSource]; //this one contains 6 UIColor objects used for the collection view cells

    UINib *cellNib = [UINib nibWithNibName:@"CustomCollectionViewCell" bundle:nil];
    [self.collectionView registerNib:cellNib forCellWithReuseIdentifier:@"customCollectionViewCellIdentifier"];
}

UICollectionViewDataSource方法如下所示：

- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
    return 1;
}


- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
    return 6;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
    CustomCollectionViewCell *customCollectionViewCell = (CustomCollectionViewCell *)[collectionView dequeueReusableCellWithReuseIdentifier:@"customCollectionViewCellIdentifier" forIndexPath:indexPath];

    UIColor *color = self.dataSource[indexPath.item];
    customCollectionViewCell.childView.backgroundColor = color;

    return customCollectionViewCell;
}

UICollectionViewDelegateFlowLayout方法如下所示：

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {

    CGSize cellSize = CGSizeMake(self.collectionView.frame.size.width / 2, self.collectionView.frame.size.height / 3);

    return cellSize;
}

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {

    return UIEdgeInsetsZero;
}

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section {

    return 0;
}

话虽如此，iPhone X上的结果似乎与iPhone 6S Plus上的结果不同。

iPhone 6S Plus结果：

iPhone X结果：

如何在iPhone X上获得相同的结果？

谢谢！