ios - Swift 4 转换 - 类型 'NSLayoutConstraint' 没有成员 'FormatOptions' 。什么是正确的电话？

Question

我有这一段代码:

let menuScrollView_constraint_H:Array = NSLayoutConstraint.constraints(withVisualFormat: "H:|[menuScrollView]|", options: NSLayoutConstraint.FormatOptions(rawValue: 0), metrics: nil, views: viewsDictionary)
let menuScrollView_constraint_V:Array = NSLayoutConstraint.constraints(withVisualFormat: "V:[menuScrollView(\(menuHeight))]", options: NSLayoutConstraint.FormatOptions(rawValue: 0), metrics: nil, views: viewsDictionary)

对于此类中的所有 NSData 类型，我不断收到“没有成员” 编译器错误。

我正在使用的这个库显然已更新到 Swift 4.2。为什么会出现这些编译器错误？

例如，我注意到有一个名为 NSLayoutFormatOptions 的公共(public)结构。我会用它来代替吗？如果是这样，我该如何使用它？

感谢您的见解

Answer 1

如果不需要指定选项，则发送一个空数组:

let menuScrollView_constraint_H:Array = NSLayoutConstraint.constraints(withVisualFormat: "H:|[menuScrollView]|", options: [], metrics: nil, views: viewsDictionary)
let menuScrollView_constraint_V:Array = NSLayoutConstraint.constraints(withVisualFormat: "V:[menuScrollView(\(menuHeight))]", options: [], metrics: nil, views: viewsDictionary)

如果需要指定选项，请从 FormatOptions 选项集中选择所需的选项，然后像下面一样编写(我使用 .alignAllBottom 作为示例):

let menuScrollView_constraint_H:Array = NSLayoutConstraint.constraints(withVisualFormat: "H:|[menuScrollView]|", options: .alignAllBottom, metrics: nil, views: viewsDictionary)
        let menuScrollView_constraint_V:Array = NSLayoutConstraint.constraints(withVisualFormat: "V:[menuScrollView(\(menuHeight))]", options: .alignAllBottom, metrics: nil, views: viewsDictionary)

可以找到带有说明的 FormatOptions 列表 here