基本上，我需要创建一个带有嵌套if / else语句的按钮，以根据选择器的选择将用户发送到不同的UIviews。 我想在If语句中链接到UIViews，但是我不知道该怎么做。 我已经尝试过导航视图（可能是错误的），而我在Google上所做的任何操作都没有帮助
Button(action: {
if (self.notations[self.notation]) == "Select" {
} else if (self.instruments[self.instrument]) == "Select" {
} else if (self.notations[self.notation]) == "Note Names" {
if (self.instruments[self.instrument]) == "Piano" {
} else if (self.instruments[self.instrument]) == "Guitar" {
} else if (self.instruments[self.instrument]) == "Saxophone" {
} else if (self.instruments[self.instrument]) == "Bass" {
}
} else if (self.notations[self.notation]) == "Treble Clef" {
if (self.instruments[self.instrument]) == "Piano" {
} else if (self.instruments[self.instrument]) == "Guitar" {
} else if (self.instruments[self.instrument]) == "Saxophone" {
} else {
}
} else if (self.notations[self.notation]) == "Bass Clef" {
if (self.instruments[self.instrument]) == "Piano" {
} else if (self.instruments[self.instrument]) == "Bass" {
} else {
}
} else if (self.notations[self.notation]) == "TAB" {
if (self.instruments[self.instrument]) == "Guitar" {
} else if (self.instruments[self.instrument]) == "Bass" {
} else {
}
} else if (self.notations[self.notation]) == "Piano" {
if (self.instruments[self.instrument]) == "Guitar" {
} else if (self.instruments[self.instrument]) == "Saxophone" {
} else if (self.instruments[self.instrument]) == "Bass" {
} else {
}
} else if (self.notations[self.notation]) == "Guitar" {
if (self.instruments[self.instrument]) == "Saxophone" {
} else if (self.instruments[self.instrument]) == "Piano" {
} else {
}
}
}) ***
答案 0 :(得分：0)
您可以尝试以下代码，并根据自己的目标进行解释。
struct WebLinkView: View {
@State private var notations: [String] = ["Select", "Note Names","Treble Clef", "Bass Clef", "Tab", "Piano","Guitar"];
@State private var instruments: [String] = ["Select", "Piano","Guitar", "Saxophone", "Bass", "Bass","Guitar"];
@State private var notation: Int = 0
@State private var instrument: Int = 0
@State private var notation_instrument: String?
var body: some View {
func target<T> (_ s: T)-> NavigationLink<Text, T> {
return NavigationLink<Text, T>("New Link: " + self.notations[self.notation] + "__" + self.instruments[self.instrument], destination: s, tag: self.notations[self.notation] + self.instruments[self.instrument], selection: $notation_instrument)
}
let nextPage = target(Text("\(self.notations[self.notation]): \(self.instruments[self.instrument])"))
let ExamplePage1 = target(Group{VStack{Text("11")
Text("Test Page")
Image(systemName: "house")
Image(systemName: "camera")
}})
let ExamplePage2 = target( Image(systemName: "heart.fill"))
return NavigationView{
Group{
VStack{
Picker(selection:self.$notation , label: Text("notation")) {
ForEach(0..<(notations.count)){ Text(self.notations[$0]).tag($0) }
}
Picker(selection:self.$instrument , label: Text("instrument")){
ForEach(0..<(instruments.count)){ Text(self.instruments[$0]).tag($0) }
}
if (self.notations[self.notation]) == "Select" {
nextPage
} else if (self.instruments[self.instrument]) == "Select" {
nextPage
} else if (self.notations[self.notation]) == "Note Names" {
if (self.instruments[self.instrument]) == "Piano" {
ExamplePage1
} else if (self.instruments[self.instrument]) == "Guitar" {
ExamplePage1
} else if (self.instruments[self.instrument]) == "Saxophone" {
ExamplePage2
} else if (self.instruments[self.instrument]) == "Bass" {
nextPage
}
} else if (self.notations[self.notation]) == "Treble Clef" {
if (self.instruments[self.instrument]) == "Piano" {
nextPage
} else if (self.instruments[self.instrument]) == "Guitar" {
nextPage
} else if (self.instruments[self.instrument]) == "Saxophone" {
nextPage
} else {
nextPage
}
} else if (self.notations[self.notation]) == "Bass Clef" {
if (self.instruments[self.instrument]) == "Piano" {
nextPage
} else if (self.instruments[self.instrument]) == "Bass" {
nextPage
} else {
nextPage
}
} else if (self.notations[self.notation]) == "TAB" {
if (self.instruments[self.instrument]) == "Guitar" {
nextPage
} else if (self.instruments[self.instrument]) == "Bass" {
nextPage
} else {
nextPage
}
} else if (self.notations[self.notation]) == "Piano" {
if (self.instruments[self.instrument]) == "Guitar" {
nextPage
} else if (self.instruments[self.instrument]) == "Saxophone" {
nextPage
} else if (self.instruments[self.instrument]) == "Bass" {
nextPage
} else {
nextPage
}
} else if (self.notations[self.notation]) == "Guitar" {
if (self.instruments[self.instrument]) == "Saxophone" {
nextPage
} else if (self.instruments[self.instrument]) == "Piano" {
nextPage
} else {
nextPage
}
}
}
}
}
}
}