ios - 在 tabitem 单击时以编程方式加载 navigationController

Question

我制作了一个 UITabBarController，当选择其中一个项目时，我加载一个图像选择器。现在，在用户从选择器中选择图像后，我想加载一个导航 Controller ，但我无法加载。我的代码是

extension BaseTabBarController : UITabBarControllerDelegate {

func  tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
    if self.viewControllers?.index(of:viewController) == 2 {
        // Presenting image picker here
        present(self.imagePicker, animated: true, completion: nil)
        return false
    } else {
        return true
    }
}

func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) {

 }

}

这是用户选择图像后的代码

extension BaseTabBarController : ImagePickerDelegate {

func doneButtonDidPress(_ imagePicker: ImagePickerController, images: [UIImage])  {

    //This is the StoryboardID of Navigationcontroller i want to goto
    let detailVC = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "UploadNavigationController")
    //This is not working
    present(detailVC, animated: true,completion: nil)
 }
}

此处未显示 Controller ，我收到此警告

Warning: Attempt to present <UINavigationController: 0x7fb4969c4800> on <BaseTabBarController: 0x7fb49780ea00> whose view is not in the window hierarchy!

我想显示导航 Controller ，标签栏在底部仍然可见

Answer 1

我想，当您想要显示导航 Controller 时，标签栏在底部仍然可见，那么您应该首先关闭图像选择器，然后推送不存在的新 Controller 。

因为如果您呈现任何 Controller 都会覆盖整个屏幕，因为它是从根 Controller 呈现的。如果您按下，它将从当前 Controller 按下，并且 tabor 保持原样。

extension BaseTabBarController : ImagePickerDelegate {

    func doneButtonDidPress(_ imagePicker: ImagePickerController, images: [UIImage]) {
        self.imagePicker.dismiss(animated: true) {
        //This is the StoryboardID of Navigationcontroller i want to goto
        let detailVC = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "UploadNavigationController")
        //This is not working
        let nav = UINavigationController(rootViewController: detailVC)
        navigationController?.pushViewController(nav, animated: true)
        //present(detailVC, animated: true,completion: nil)
    }
}