< How to create scrolling pages of content using tabViewStyle()

How to group views together

Paul Hudson @twostraws February 9th 2021

Updated for Xcode 12.5

If you need several views to act as one – for example, to transition together – then you should use SwiftUI’s Group view. This is particularly important because, for underlying technical reasons, you can only add up to 10 views to a parent view at a time.

To demonstrate this, here’s a VStack with 10 pieces of text:

VStack {
    Text("Line")
    Text("Line")
    Text("Line")
    Text("Line")
    Text("Line")
    Text("Line")
    Text("Line")
    Text("Line")
    Text("Line")
    Text("Line")
}

That works just fine, but if you try adding an eleventh piece of text, you’ll get an error like this one: ambiguous reference to member 'buildBlock()’.

…almost certainly followed by a lot more error text.

This is because SwiftUI’s view building system has various code designed to let us add 1 view, 2 views, 3 views, or 4, 5, 6, 7, 8, 9, and 10 views, but not for 11 and beyond – that doesn’t work.

Fortunately, we can use a group like this:

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

    Group {
        Text("Line")
        Text("Line")
        Text("Line")
        Text("Line")
        Text("Line")
    }
}

That creates exactly the same result, except now we can go beyond the 10 view limit because the VStack contains only two views – two groups.