问题

在SwiftUI中，您可以使用GeometryReader和Spacer来实现您所描述的布局。以下是示例代码：

import SwiftUI

struct ContentView: View {
    var body: some View {
        VStack {
            // 1st subview with fixed size
            Text("Subview 1")
                .frame(height: 50)
            
            // 2nd subview in the middle, taking the rest of available height
            GeometryReader { geometry in
                Text("Subview 2")
                    .frame(height: geometry.size.height - 100) // Adjust the value as needed
            }
            
            // 3rd subview with fixed size
            Text("Subview 3")
                .frame(height: 50)
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

请注意，上述示例中的值可能需要根据设备和布局需求进行调整。

答案1

得分: 1

以下是已翻译好的代码部分：

    struct TestSwiftUIView: View {
    var body: some View {
        VStack {
            HStack { //视图 1 - 固定
            }
            .frame(maxWidth: .infinity, minHeight: 100)
            .background(Color.red)
            HStack { //视图 2 - 扩展
            }
            .frame(maxWidth: .infinity, maxHeight: .infinity)
            .background(Color.blue)
            HStack { //视图 3 - 固定
            }
            .frame(maxWidth: .infinity, minHeight: 100)
            .background(Color.green)
        }
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(Color.black)
    }
}

struct TestSwiftUIView: View {
var body: some View {
    VStack {
        HStack { //View 1 - fixed
        }
        .frame(maxWidth: .infinity, minHeight: 100)
        .background(Color.red)
        HStack { //View 2 - expanded
        }
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(Color.blue)
        HStack { //View 3 - fixed
        }
        .frame(maxWidth: .infinity, minHeight: 100)
        .background(Color.green)
    }
    .frame(maxWidth: .infinity, maxHeight: .infinity)
    .background(Color.black)
}