在 SwiftUI 中，如何判断 Text 是否被截断？

struct ContentView1: View {
    // MARK: - Sample Data
    private let short = "short Text"
    private let medium =
        "some text which can obviously be wrapped in two lines"
    private let long = "A lot of text which can obviously be wrapped in many lines!"

    var body: some View {
        List {
            AdaptiveAmountRow(title: short)
            AdaptiveAmountRow(title: medium)
            AdaptiveAmountRow(title: long)
        }
    }
}

// 三种预设布局方案

/// Compact layout - 单行水平排列
HStack(alignment: .center) { 
    titleView // maxLines = 1
    Spacer(minLength: 2)
    amountView.fixedSize() // 金额永不截断
}

/// Standard layout - 两行水平排列
HStack(alignment: .lastTextBaseline) {
    titleView // maxLines = 2
    Spacer(minLength: 2)
    amountView.fixedSize()
}

/// Extended layout - 垂直排列
VStack(alignment: .leading) {
    titleView // maxLines = nil (不限制)
    HStack {
        Spacer()
        amountView.fixedSize()
    }
}

struct Dimension: View {
    private let long = "A lot of text which can obviously be wrapped in many lines!"
    var body: some View {
        Text(long)
            .border(Color.red, width: 2)
            .fixedSize(horizontal: false, vertical: true)
            .background(
                GeometryReader { geometry in
                    Color.clear
                        .task(id: geometry.size) {
                            print(geometry.size) // 100.0 x 108.3
                        }
                })
            .frame(width: 100, height: 50)
            .border(.blue, width: 2)
    }
}

struct Dimension: View {
    private let long = "A lot of text which can obviously be wrapped in many lines!"
    @State private var displayDimension: CGSize?
    @State private var verticalDimension: CGSize?
    @State private var horizontalDimension: CGSize?
		
    var isTruncated: Bool? {
        guard let displayDimension, let verticalDimension, let horizontalDimension else { return nil }
        // 检查是否在任一维度上被截断
        if displayDimension.width > verticalDimension.width || displayDimension.height > horizontalDimension.height {
            return true
        } else {
            return false
        }
    }
    
    var body: some View {
        Text(long)
            .getDimension(dimension: $displayDimension)
            .background(
                Text(long) // 在宽度限制的情况下，完整显示最少需要的高度
                    .fixedSize(horizontal: false, vertical: true)
                    .hidden()
                    .getDimension(dimension: $verticalDimension)
             )
            .background(
                Text(long) // 在高度限制的情况下，完整显示最少需要的宽度
                    .fixedSize(horizontal: true, vertical: false)
                    .hidden()
                    .getDimension(dimension: $horizontalDimension)
                )
            .frame(width: 100, height: 50)
        
        if let isTruncated  {
            Text(isTruncated ? "Truncated" : "Not Truncated")
        }
    }
}

struct ZStackContainer: View {
    @State private var layoutStatuses: [LayoutMode: Bool] = [:]

    /// The first layout mode that can display the content without truncation
    private var optimalLayoutMode: LayoutMode? {
        return layoutStatuses.keys
            .sorted(by: { $0 < $1 })
            .first { !(layoutStatuses[$0] ?? true) }
    }

    private func isLayoutSelected(_ mode: LayoutMode) -> Bool {
        return optimalLayoutMode == mode
    }
    
    var body: some View {
        ZStack {
            Compact()
                .layoutPriority(isLayoutSelected(.compact) ? 2 : 1)
                .opacity(isLayoutSelected(.compact) ? 1 : 0)

            Standard()
                .layoutPriority(isLayoutSelected(.standard) ? 2 : 1)
                .opacity(isLayoutSelected(.standard) ? 1 : 0)

            Extended()
                .layoutPriority(isLayoutSelected(.extended) ? 2 : 1)
                .opacity(isLayoutSelected(.extended) ? 1 : 0)
        }
    }
}