SwiftUI 4 List initializer not available in iOS

Question

When creating a list, previous versions of Xcode allowed for the following on iOS:

List(tabs, selection: $lastTab) {tab in
…
}

This now gives an error:

'init(_:selection:rowContent:)' is unavailable in iOS

also true for

List(tabs, id:\.self, selection: $lastTab)

and other variations such as:

List(selection: $lastTab) {
   ForEach(tabs, id:\.self) {tab in 
...
}

Has anyone else run into this problem?

I have the same issue, but in my case, the editor gave me a "fix" option that inserted an unusual looking autocomplete for the list. — Stoic, Jul 09 '22 at 00:09
Apple's tutorial from 2022 is having the same error https://developer.apple.com/tutorials/swiftui-concepts/defining-the-source-of-truth-using-a-custom-binding — Jonny, Feb 02 '23 at 05:31

score 50 · Accepted Answer · edited Aug 23 '22 at 09:47

50

You probably forgot to make selection as Optional, ie.

@State private var lastTab: Int? = 0   // << here !! `Int?`

List(tabs, selection: $lastTab) {tab in
// ...
}

Verified with: Xcode 14b3 / iOS 16

edited Aug 23 '22 at 09:47

Martijn Pieters

answered Jul 09 '22 at 05:04

Asperi

7

The error message is misleading. – winner.ktw Mar 04 '23 at 14:26
Be aware that this might lead to issues with `.sheet`/`.popover`! For me using an optional for the `TabView` selection always switched back to the first tab when presenting the sheet. To workaround this I’ve bridged the optional binding to a non-optional binding. – alexkaessner Jun 23 '23 at 08:15

1 Answers1