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swiftswiftuiios14widgetkit

Update Widget when appearance changes

I would need to know if any of you know a system in SwiftUI to update a Widget when the appearance changes from light mode to dark mode and vice versa.

I can change text and images but I use a method to display a screenshot of a map and I should run it every time the appearance changes to get the correct map color.

Solution
    1. Create two screenshots (one per theme) and pass it in the entry:
    struct SimpleEntry: TimelineEntry {
    let date: Date
    let mapScreenshots: [ColorScheme: Image]
}

    struct Provider: TimelineProvider {
    ...

    func getTimeline(in context: Context, completion: @escaping (Timeline<SimpleEntry>) -> Void) {
        let entry = SimpleEntry(
            date: Date(),
            mapScreenshots: [
                // replace with actual map screenshots
                .dark: Image(systemName: "plus"),
                .light: Image(systemName: "minus"),
            ]
        )
        let timeline = Timeline(entries: [entry], policy: .never)
        completion(timeline)
    }
}
    1. Use @Environment(\.colorScheme) to react to theme changes:
    struct WidgetEntryView: View {
    @Environment(\.colorScheme) var colorScheme

    var entry: Provider.Entry

    var body: some View {
        if let screenshot = entry.mapScreenshots[colorScheme] {
            screenshot
        }
    }
}