Dynamic layouts with multi-line Text views

I have something that works though it's not ideal from a performance perspective; so definitely worth filing a follow up feedback as a request to simplify this and make it cheaper:

struct ContentView: View {
    var content: String {
        "This is some text which we hope will fit on two lines"
    }

    var body: some View {
        // Reserve two lines (always)
        Text(content)
            .hidden()
            .lineLimit(2, reservesSpace: true)
            .accessibilityHidden(true)
            .overlay {
                ViewThatFits(in: .vertical) {
                    ZStack {
                        // Measurer: reports the full unwrapped height at the proposed width.
                        // Drives the fit check; never visible.
                        Text(content)
                            .fixedSize(horizontal: false, vertical: true)
                            .hidden()
                            .accessibilityHidden(true)

                        // Renderer: the actual 2-line layout.
                        Text(content)
                            .lineLimit(2, reservesSpace: true)
                    }

                    Text("Backup")
                        .lineLimit(2, reservesSpace: true)
                }
            }
    }
}

Note: It is possible you don't need the outer hidden Text if there's other things to constrain your view but this was an easy way to set of a small sample app that shows the behavior.

I tried your idea in my sample, but it doesn't work for me: The problem is, that I need to check whether the two-line text fits horizontally side-by-side to other views, and if not use a completely different layout where the same text has the whole width and the other views are below. See this sample:

struct AmountRowView: View {
    let title: String
    let amount: String = "$ 10.00"      // could vary, doesn't matter for the problem

    var body: some View {
        let titleView = Text(title)
            .multilineTextAlignment(.leading)

        let amountView = Text(amount)
            .border(.gray)

        let shortLayout = HStack(alignment: .center) {
            titleView.border(.green)
            Spacer(minLength: 2)
            amountView
        } // green = short

        let mediumLayout = HStack(alignment: .lastTextBaseline) {
            ZStack {
                // Measurer: reports the full unwrapped height at the proposed width.
                // Drives the fit check; never visible.
                Text(title)
                    .fixedSize(horizontal: false, vertical: true)
                    .hidden()
                    .accessibilityHidden(true)

                // Renderer: the actual 2-line layout.
                Text(title)
                    .lineLimit(2, reservesSpace: true)
            }
            .border(.red)
//                .lineLimit(2, reservesSpace: true)
//                .fixedSize(horizontal: false, vertical: true)
            Spacer(minLength: 2)
            amountView
        } // red = medium

        let longLayout = VStack(alignment: .leading) {
            titleView.border(.blue)
            HStack {
                Spacer()
                amountView
            }
        } // blue = long

        ViewThatFits(in: .horizontal) {
            shortLayout
            mediumLayout
            longLayout   // <=== comment / uncomment this line, then change dynamic fontSize
        }
    }
}

struct ContentView: View {
    var body: some View {
        List {
            Section {
                // should fit in greenV when font <= AX2
                AmountRowView(title: "Short title:")

                // should fit in redV from XXlarge to AX1
                AmountRowView(title: "Medium title, more text:")

                // needs blueV with fontsize >= XXlarge, smaller font fits in redV
                AmountRowView(title: "Long title with way more text to show here:")
            } header: { Text("ViewThatFits") }
        }
    }
}

When you comment out longLayout (line 49), you'll see that mediumLayout fits for the middle row, but is not taken from ViewThatFits if longLayout is the 3rd option.