实例成员'count'不能用于类型 'TweetFilterOptions.AllCases'

Question

我正在制作一个swiftUI应用程序，我有一个enum。在View结构中，我将获得var n = TweetFilterOptions.AllCases.count的案例数。但是我得到一个错误:

Instance member 'count' cannot be used on type 'TweetFilterOptions.AllCases' (aka 'Array<TweetFilterOptions>'); did you mean to use a value of this type instead?

我的代码是这样的:

enum TweetFilterOptions: Int, CaseIterable{
case tweets
case replies
case likes

var title:String{
switch self{
case .tweets:
return "tweets"
case .replies:
return "tweets and replies"
case .likes:
return "likes"
}
}
}
struct FilterButtonView: View {
var n = TweetFilterOptions.AllCases.count // Here I am getting the error.
var body: some View {
VStack(alignment:.leading){
HStack{
ForEach(TweetFilterOptions.allCases, id:.self){ options in
Text(options.title)
}
}
Rectangle()
.frame(width: 300, height: 3)
.foregroundColor(.blue)
.animation(.spring())
}
}
}

如何消除此错误并获得枚举中所有案例的数量?

Answer 1

使用。allcases代替。allcases。这样的

var n = TweetFilterOptions.allCases.count