我正在尝试仅使用代码创建UIButton。我通过SIGABORT收到了此消息,但我没有使用主故事板。我不确定主故事板中是否还有元素。
我该如何解决?
override func viewDidLoad() {
super.viewDidLoad()
let button:UIButton = UIButton(frame: CGRect(x: 340, y: 10, width: self.view.frame.width, height: self.view.frame.height / 4))
button.backgroundColor = .white
button.setTitle("filter", for: .normal)
button.setTitleColor(.blue, for: .normal)
button.addTarget(self, action: #selector(pushButton), for: .touchUpInside)
self.view.addSubview(button)
}
@objc func pushButton(sender: UIButton){
print("button pushed")
}
如果您具有XCode 11+,则需要在SceneDelegate上设置rootViewController,并且可以这样进行:
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
var window: UIWindow?
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
guard let windowScene = (scene as? UIWindowScene) else { return }
window = UIWindow(frame: windowScene.coordinateSpace.bounds)
window?.windowScene = windowScene
self.window?.rootViewController = YourViewController() //UINavigationController(rootViewController: YourViewController()) this if you want your controller to be inside navigation.
window?.makeKeyAndVisible()
}
func sceneDidDisconnect(_ scene: UIScene) {
// Called as the scene is being released by the system.
// This occurs shortly after the scene enters the background, or when its session is discarded.
// Release any resources associated with this scene that can be re-created the next time the scene connects.
// The scene may re-connect later, as its session was not neccessarily discarded (see `application:didDiscardSceneSessions` instead).
}
func sceneDidBecomeActive(_ scene: UIScene) {
// Called when the scene has moved from an inactive state to an active state.
// Use this method to restart any tasks that were paused (or not yet started) when the scene was inactive.
}
func sceneWillResignActive(_ scene: UIScene) {
// Called when the scene will move from an active state to an inactive state.
// This may occur due to temporary interruptions (ex. an incoming phone call).
}
func sceneWillEnterForeground(_ scene: UIScene) {
// Called as the scene transitions from the background to the foreground.
// Use this method to undo the changes made on entering the background.
}
func sceneDidEnterBackground(_ scene: UIScene) {
// Called as the scene transitions from the foreground to the background.
// Use this method to save data, release shared resources, and store enough scene-specific state information
// to restore the scene back to its current state.
}
}
此外,您还需要从目标常规设置中删除'主界面'字段,请检查下图: