以编程方式向ViewController单元格添加约束条件

Question

使用CollectionViewCells创建“卡片式”菜单，我需要在任何屏幕大小下，让这些单元格之间的间距相同，就像|------|一样。我已经实现了以下效果：

addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|-15-[v0]-15-|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": appsCollectionView]))

addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[v0]|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": appsCollectionView]))

我已将屏幕两侧的边距设置为15，但每当我在更大的屏幕上加载应用时，间隔的空间也会改变。

我尝试使用以下方法：

appsCollectionView.leadingAnchor.constraint(equalTo: trailingAnchor).isActive = true

但我收到了这个日志：

2016-12-07 16:51:14.902586 AppStoreClone[8843:206635] [LayoutConstraints] Unable to simultaneously satisfy constraints.
    Probably at least one of the constraints in the following list is one you don't want. 
    Try this: 
        (1) look at each constraint and try to figure out which you don't expect; 
        (2) find the code that added the unwanted constraint or constraints and fix it. 
(
    "<NSLayoutConstraint:0x608000283fc0 H:[UICollectionView:0x7f8172010200]-(15)-|   (active, names: '|':AppStoreClone.CategoryCell:0x7f8173309710 )>",
    "<NSLayoutConstraint:0x608000284100 H:[AppStoreClone.CategoryCell:0x7f8173309710]-(0)-[UICollectionView:0x7f8172010200]   (active)>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x608000284100 H:[AppStoreClone.CategoryCell:0x7f8173309710]-(0)-[UICollectionView:0x7f8172010200]   (active)>

- Joe Sene

Answer 1

将控件放置在Stack View中，并实现自动布局。

https://developer.apple.com/library/content/documentation/UserExperience/Conceptual/AutolayoutPG/LayoutUsingStackViews.html

- CodeRo