AspectRatioModifier

AspectRatioModifier.swift

public extension View {
    func aspectRatioControlled(_ ratio: CGFloat) -> some View {
        modifier(AspectRatioModifier(aspectRatio: ratio))
    }
}
// https://gist.github.com/Priva28/53abcdef7de6633d776cb169c96ce014
struct AspectRatioModifier: ViewModifier {

    var aspectRatio: CGFloat
    @State private var setSize: CGSize?
    
    func body(content: Content) -> some View {
        GeometryReader { geo in
            content
                .onChange(of: aspectRatio) { _, aspectRatio in
                    setWindowAspectRatio(aspectRatio: aspectRatio, originalSize: geo.size)
                }
                .onAppear {
                    setWindowAspectRatio(aspectRatio: aspectRatio, originalSize: geo.size)
                }
        }
        .frame(width: setSize?.width, height: setSize?.height)
    }
    
    private func setWindowAspectRatio(aspectRatio: CGFloat, originalSize: CGSize) {
        let originalAspectRatio = originalSize.width / originalSize.height
        
        var newWidth: CGFloat
        var newHeight: CGFloat
        
        if aspectRatio > originalAspectRatio {
            newWidth = originalSize.height * aspectRatio
            newHeight = originalSize.height
            
//            if newWidth > maxWidth {
//                newWidth = maxWidth
//                newHeight = newWidth / aspectRatio
//            }
        } else {
            newHeight = originalSize.width / aspectRatio
            newWidth = originalSize.width
            
//            if newHeight > maxHeight {
//                newHeight = maxHeight
//                newWidth = newHeight * aspectRatio
//            }
        }
        
//        newWidth = min(newWidth, maxWidth)
//        newHeight = min(newHeight, maxHeight)
        
        let newSize = CGSize(width: newWidth, height: newHeight)
        
        setResizingRestrictions(.none)
        withAnimation(nil) {
            setSize = newSize
        }
        
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
            setResizingRestrictions(.uniform)
            setSize = nil
        }
    }
    
    private func setResizingRestrictions(_ restrictions: UIWindowScene.ResizingRestrictions) {
        guard let windowScene = UIApplication.shared.connectedScenes.first as? UIWindowScene else {
            return
        }
        windowScene.requestGeometryUpdate(.Vision(resizingRestrictions: restrictions))
    }
}