为什么 SwiftUI 中的 Today App Extension Widget 是白色的？

Question

just like this

and my view is simply:

Text("Testing Widget")

and tried this:

VStack {
    Text("Testing Widget")
}
.background(Color(UIColor.clear))

and nothing happend:(.

Answer 1

Just came across a solution for me!

You have to set the backgroundColor of the UIHostingController 's view to .clear , and then it will work. You don't need to set the background color of the SwiftUI view.

let hostingController = UIHostingController(rootView: SwiftUIView())

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.

    view.addSubview(hostingController.view)
    addChild(hostingController)
    hostingController.didMove(toParent: self)

    // You may want to add constraints

    hostingController.view.backgroundColor = .clear // <- IMPORTANT
}