Using isActivityFullscreen to build applications in xcode 16 will crash in ios 17

Question

Created Jan ’25

Replies 2

Boosts 0

Participants 3

My widget uses the @Environment(.isActivityFullscreen) variable. When running on ios 17, it will crash and report an error: dyld[55031]: Symbol not found: _$s7SwiftUI17EnvironmentValuesV9WidgetKitE20isActivityFullscreenSbvg Expected in: /Library/Developer/CoreSimulator/Volumes/iOS_21E213/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS 17.4.simruntime/Contents/Resources/RuntimeRoot/System/Library/Frameworks/WidgetKit.framework/WidgetKit

Answer 1

pavelfromminsk OP

Jun ’25

Any luck to find a workaround?

Documentation still says it's fine, but unfortunately - it is not.

https://developer.apple.com/documentation/swiftui/environmentvalues/isactivityfullscreen

Answer 2

RogerLee OP

2h

I encountered the same situation, but the version is Xcode 27 Beta 6, and the device is iOS 17. The minimal reproducible code is as follows:

import SwiftUI
import WidgetKit

@main
struct Xcode27LACrashApp: App {
    @Environment(\.isActivityFullscreen) private var isActivityFullscreen
    var body: some Scene {
        WindowGroup {
            Text(isActivityFullscreen ? "fullscreen" : "not fullscreen")
        }
    }
}

Crash info:

dyld[712]: Symbol not found: _$s7SwiftUI17EnvironmentValuesV9WidgetKitE20isActivityFullscreenSbvg Referenced from: <6C188284-51F7-38B5-833C-13FDC11E4C2C> /private/var/containers/Bundle/Application/71A82AE6-495A-45AA-B823-A2E2597D6F6E/Xcode27LACrash.app/Xcode27LACrash.debug.dylib Expected in: <064E500D-3AE0-34EC-9759-52B592E7B15A> /System/Library/Frameworks/WidgetKit.framework/WidgetKit

FB24532892