ForEach & indexof SwiftUI keep giving "Closure containing control flow statement cannot be used-CodePudding

I'm trying to make a ForEach loop that finds the index of the currently selected picker value. But I keep getting these error messages: Referencing initializer 'init(_:id:content:)' on 'ForEach' requires that 'Text' conform to 'TableRowContent', Static method 'buildBlock' requires that 'Text' conform to 'TableRowContent', Closure containing control flow statement cannot be used with result builder 'TableRowBuilder'

@State private var loc: Double = 0
@State private var selectedLine = "N Q R W"

Picker("Lines", selection: $selectedLine) {
   ForEach(station.groups, id: \.self) {
      Text($0)
   }
}
.padding(.all, 6.0)
.pickerStyle(.segmented)

ForEach (0 ..< station.groups.count, id: \.self) { i in //first 2 errors here
   Text("Value: \(station.groups[i])")
   if station.groups[i] == selectedLine { //second error
      loc = station.groups.index(of: selectedLine)
   }
}

station.group is non-static variable from a JSON file. An example is ["N Q R W","one two three"] or ["A C E","B D F M"] Many thanks in advance.

Edit: I found a work around.

Picker("Lines", selection: $selectedLine) {
   ForEach(0..<station.groups.count, id: \.self) { i in
      Text(station.groups[i])
   }
}
.padding(.all, 6.0)
.pickerStyle(.segmented)

selectedLine is an Int, now it outputs 0, 1, 2, & 3 instead of the array values.

CodePudding user response：

ForEach is a View it isn't a for loop and you can't use \.self or use array.count, you have to supply a key that is a unique identifier for the data, or make your data struct implement Identifiable and have a let id set it from the JSON data.