为什么我不能将根视图中的数据分配到其嵌入式容器视图中?

Why can't I assign data from the root view onto its embedded container view?

我有一个 DetailViewController 有一个 container 视图。将出现的第一个容器视图是 DetailChildViewController.

DetailChildViewController 包含一个集合视图,它将显示子视图的属性。但是,即使我在 prepare(for segue:) 函数中将数据分配给 detailChildVC 的属性,DetailChildViewController 中的属性变量仍然 returns nil。我该如何解决这个问题?

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

        // Set the currentViewController to description child VC because that is the first one
        // shown in the container view
        if segue.identifier == "DetailChildSegue" {
            let detailChildVC = DetailChildViewController()
            // Set product of the childVC
            let actionArray = [product?.action.keys.description] as? [String]
            detailChildVC.properties = actionArray
        }
        // Set the currentVC
        currentVC = segue.destination
    }

您分配给一个新变量 DetailChildViewController() 而不是目标

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

    if segue.identifier == "DetailChildSegue" {

        let detailChildVC = segue.destination as! DetailChildViewController

        let actionArray = [product?.action.keys.description] as? [String]

        detailChildVC.properties = actionArray
    }

    // Set the currentVC

    currentVC = segue.destination
}