我正在尝试为某些动画实现CADisplayLink，但是当我尝试从类MainData内部访问MyAnimations环境对象属性时，出现致命错误{{1 }}
在SceneDelegate中，我将No ObservableObject of type MainData found. A View.environmentObject(_:) for MainData may be missing as an ancestor of this view.设置为MainData上的环境对象：
ContentView这是class SceneDelegate: UIResponder, UIWindowSceneDelegate {
var window: UIWindow?
var mainData = MainData()
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
// Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
// If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
// This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
// Create the SwiftUI view that provides the window contents.
let contentView = ContentView()
// Use a UIHostingController as window root view controller.
if let windowScene = scene as? UIWindowScene {
let window = UIWindow(windowScene: windowScene)
window.rootViewController = UIHostingController(rootView: contentView.environmentObject(self.mainData))
self.window = window
window.makeKeyAndVisible()
}
}
...
}
的课程。从CADisplayLink调用createDisplayLink()：
ContentView 我的问题是：如何从class MyAnimations: NSObject{
@EnvironmentObject var mainData: MainData
func createDisplayLink() {
let displaylink = CADisplayLink(target: self, selector: #selector(step))
displaylink.add(to: .current, forMode: RunLoop.Mode.default)
}
@objc func step(link: CADisplayLink) {
mainData.displayLinkY += 1.5 //Error here
mainData.displayLinkX += 1.5
}
}
内部更改环境对象属性displayLinkX和displayLinkY？
答案 0 :(得分：0)
只需删除@EnvironmentObject属性包装器，仅适用于SwiftUI
class MyAnimations: NSObject{
var mainData: MainData
init(mainData: MainData) {
self.mainData = mainData
super.init()
}
// ... other code
}