How to fix “Ambiguous reference to member 'buildBlock()’”

Paul Hudson    @twostraws    October 14th 2019

Fully updated for Xcode 11.1

SwiftUI allows a maximum of 10 static children in each container, so if you try to add 11 or more you’ll get this error. To be clear, this means the following code is valid:

VStack {
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
    Text("SwiftUI")
}

But if you add a single more Text("SwiftUI") then the code will refuse to build.

To fix this problem, wrap your items in groups of 10 or fewer, like this:

VStack {
    Group {
        Text("SwiftUI")
        Text("SwiftUI")
        Text("SwiftUI")
        Text("SwiftUI")
        Text("SwiftUI")
        Text("SwiftUI")
    }

    Group {
        Text("SwiftUI")
        Text("SwiftUI")
        Text("SwiftUI")
        Text("SwiftUI")
        Text("SwiftUI")
    }
}

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