jgale / StateBugiOS14

An example showing a scenario where @State vars don't work on iOS 14

Bug Description

I have a List of GroupedListStyle() with 2 Sections.

When I tap on one of the items in the Section, it sets an optional ListItem var shownItem to the item that was tapped. It also sets a showSheet @State var to display the sheet.

    @State var showSheet = false
    @State var shownItem: ListItem?

However, in the .sheet() modifier, the shownItem has somehow been re-initialized and become nil. This should not happen.

I say "reinitialized" because I've also tried it by storing a non-optional UUID as a @State var, i.e. @State var shownItemUUID = UUID() In that case, the var also got reinitialized to a new UUID in the .sheet() modifier.

Steps to reproduce

Version 12.0 beta (12A6159). iPhone 11 Pro Simulator (iOS 13.5 and iOS 14)

1. Run the app
2. Tap on the Item A text

iOS 13:

• Shows a sheet with "Item A" (correct)

iOS 14:

• Shows a sheet with a red color view (incorrect)

I believe this is a regression on iOS 14.

I've filed a Feedback with Apple: FB7776085.