SwiftUI fails to build preview with compiling error

Question

When I go to view my SwiftUI through the canvas preview in Xcode 11.3.1 I am getting the error

Compiling failed: 'Color' is only available in iOS 13.0 or newer

But the project itself builds successfully and the simulator loads without any issues. I have tried clearing the build folder, quitting Xcode and rebuilding but still no luck.

Any help would be great. Thanks in advance.

Is this SwiftUI only project? Which is deployment target version? — Asperi
@Asperi No, the project also has files using UIKIt and the deployment target is 11.4. Thanks — user2047296
I don't get the question. If your deployment target is 11.4 but Color is only available in 13.0, then that's the issue. Just bump up the deployment target to 13.0, or don't use Color. — LinusGeffarth

Asperi Asperi · Accepted Answer · 2020-05-15T15:42:13

SwiftUI minimum deployment target is 13.0, so if you have project with support of older version, then all SwiftUI code (including preview providers) you have to prepend with availability modifier, like

@available(iOS 13.0, *)  // << here !!
struct Demo: View {
    var body: some View {
        VStack {
            Text("Hello")
        }
    }
}

SwiftUI fails to build preview with compiling error

3 Answers