如何在SwiftUI中获取屏幕宽度？

Question

我想将“图像”帧的大小调整为一个正方形，该正方形占用屏幕的相同宽度，因此高度的值（屏幕宽度）相同。

以下代码不起作用，因为它使图像具有相同的视图高度。

public class DataWrapper<T extends MyCategory> {
private T data;
private EventType type;
            // getters and setters omitted for the sake of brevity
}

Answer 1

尝试使用Geometry Reader

let placeholder = UIImage(systemName: "photo")! // SF Symbols

struct ContentView: View {
    var body: some View {
        GeometryReader { geometry in
            Image(uiImage: placeholder) 
            .resizable()
            .frame(width: geometry.size.width, height: geometry.size.width, alignment: .center)
            // .frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .center)
            .clipped()
        }
    }
}

Answer 2

您可以为此创建一个UIScreen扩展名。喜欢：

extension UIScreen{
   static let screenWidth = UIScreen.main.bounds.size.width
   static let screenHeight = UIScreen.main.bounds.size.height
   static let screenSize = UIScreen.main.bounds.size
}

用法：

UIScreen.screenWidth

Answer 3

最简单的方法是使图像可调整大小并将其纵横比设置为1：

var body: some View {
    Image("someImage")
       .resizable()
       .aspectRatio(1.0, contentMode: .fit)
}

Answer 4

您可以使用UIScreen.main.bounds .width 或 .height

.frame(
   width:UIScreen.main.bounds.width,
   height:UIScreen.main.bounds.height
)