在 SwiftUI 中根据文本高度自动调整视图高度

Question

我正在尝试在 SwiftUI 中创建一个视图，其中左侧图像的背景应根据右侧文本的高度垂直缩放。

我尝试了很多不同的方法，从GeometryReader到.layoutPriority()，但我没有设法让它们中的任何一个工作。

当前状态：

期望状态：

我知道我可以通过.frame(100)对我发布的示例进行硬编码来模仿该功能，但是由于右侧的文本是动态的，所以这是行不通的。

这是屏幕截图中视图的完整代码：

import SwiftUI

struct DynamicallyScalingView: View {
    var body: some View {
        HStack(spacing: 20) {
            Image(systemName: "snow")
                .font(.system(size: 32))
                .padding(20)
                .background(Color.red.opacity(0.4))
                .cornerRadius(8)

            VStack(alignment: .leading, spacing: 8) {
                Text("My Title")
                    .foregroundColor(.white)
                    .font(.system(size: 13))
                    .padding(5)
                    .background(Color.black)
                    .cornerRadius(8)
                Text("Dynamic text that can be of different leghts. Spanning from one to multiple lines. When it's multiple lines, the background on the left should scale vertically")
                    .font(.system(size: 13))
            }
        }
        .padding(.horizontal)
    }
}

struct DailyFactView_Previews: PreviewProvider {
    static var previews: some View {
        DynamicallyScalingView()
    }
}

Answer 1

这是没有解决方法的答案。

struct DynamicallyScalingView: View {
    var body: some View {
        HStack(spacing: 20) {
            Image(systemName: "snow")
                .frame(maxHeight: .infinity)          // Add this
                .font(.system(size: 32))
                .padding(20)
                .background(Color.red.opacity(0.4))
                .cornerRadius(8)

            VStack(alignment: .leading, spacing: 8) {
                Text("My Title")
                    .foregroundColor(.white)
                    .font(.system(size: 13))
                    .padding(5)
                    .background(Color.black)
                    .cornerRadius(8)
                Text("Dynamic text that can be of different leghts. Spanning from one to multiple lines. When it's multiple lines, the background on the left should scale vertically")
                    .font(.system(size: 13))
            }
            .frame(maxHeight: .infinity)              // Add this
        }
        .padding(.horizontal)
        .fixedSize(horizontal: false, vertical: true) // Add this
    }
}

Answer 2

这是基于视图首选项键的解决方案。使用 Xcode 11.4 / iOS 13.4 测试

struct DynamicallyScalingView: View {
    @State private var labelHeight = CGFloat.zero     // << here !!

    var body: some View {
        HStack(spacing: 20) {
            Image(systemName: "snow")
                .font(.system(size: 32))
                .padding(20)
                .frame(minHeight: labelHeight)       // << here !!
                .background(Color.red.opacity(0.4))
                .cornerRadius(8)

            VStack(alignment: .leading, spacing: 8) {
                Text("My Title")
                    .foregroundColor(.white)
                    .font(.system(size: 13))
                    .padding(5)
                    .background(Color.black)
                    .cornerRadius(8)
                Text("Dynamic text that can be of different leghts. Spanning from one to multiple lines. When it's multiple lines, the background on the left should scale vertically")
                    .font(.system(size: 13))
            }
            .background(GeometryReader {      // << set right side height
                Color.clear.preference(key: ViewHeightKey.self, 
                    value: $0.frame(in: .local).size.height) 
            })
        }
        .onPreferenceChange(ViewHeightKey.self) { // << read right side height
            self.labelHeight = $0        // << here !!
        }
        .padding(.horizontal)
    }
}

struct ViewHeightKey: PreferenceKey {
    static var defaultValue: CGFloat { 0 }
    static func reduce(value: inout Value, nextValue: () -> Value) {
        value = value + nextValue()
    }
}