与SwiftUI中的文本内容相同的矩形的动态高度

import SwiftUI

struct ContentView: View {
    var body: some View {
        VStack {
            RoundedRectangle(cornerRadius: 10)
                .fill(Color.blue)
                .frame(height: textHeight)
                .overlay(
                    Text("这是一个动态高度的文本矩形框")
                        .foregroundColor(.white)
                        .padding()
                )
        }
        .frame(maxWidth: .infinity, alignment: .center)
    }
    
    var textHeight: CGFloat {
        let text = "这是一个动态高度的文本矩形框"
        let font = UIFont.systemFont(ofSize: 16)
        let textWidth = CGFloat.greatestFiniteMagnitude
        let textHeight = text.height(withConstrainedWidth: textWidth, font: font)
        return textHeight + 20 // 增加一些 padding
    }
}

extension String {
    func height(withConstrainedWidth width: CGFloat, font: UIFont) -> CGFloat {
        let constraintRect = CGSize(width: width, height: .greatestFiniteMagnitude)
        let boundingBox = self.boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [.font: font], context: nil)
        return ceil(boundingBox.height)
    }
}

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