How can I get the displayGamut from UITraitCollection in SwiftUI?-CodePudding

I'm in the process of migrating some code from UIKit to SwiftUI and I ran into an issue where displayGamut (e.g. sRGB vs. Display P3) does not appear to be available in the @Environment of SwiftUI. In UIKit you can get this from UITraitCollection.

Is there a way to get this natively in SwiftUI? If not, is there a way I can plumb this down into SwiftUI from the UIKit layer it's embedded in?

CodePudding user response：

You can do this by creating your own custom EnvironmentKey for displayGamut, e.g.

struct DisplayGamut: EnvironmentKey {
    static var defaultValue: UIDisplayGamut {
        UITraitCollection.current.displayGamut
    }
}

extension EnvironmentValues {
    var displayGamut: UIDisplayGamut {
        self[DisplayGamut.self]
    }
}


struct ContentView: View {
    
    @Environment(\.displayGamut) var displayGamut
    
    var body: some View {
        VStack {
            switch displayGamut {
            case .P3:
                Text("displayGamut: P3")
            case .SRGB:
                Text("displayGamut: SRGB")
            case .unspecified:
                Text("displayGamut: unspecified")
            @unknown default:
                fatalError()
            }
        }
    }
}