ios - Cannot resolve error encountered when creating auto layout constraint for view to have a specific height

Question

When trying to have a bar with subviews at a specific height, I encounter this error and have not been able to resolve it yet.

Unable to parse constraint format: Options mask required views to be aligned on a vertical edge, which is not allowed for layout that is also vertical. V:|[mainView][barView(==50)]|

Answer 1

当您垂直堆叠视图时，您需要选择水平对齐方式，例如 NSLayoutFormatAlignAllLeft 以便布局系统知道如何排列它们。