显示来自 AppDelegate 的两个 ViewController [英] Show two ViewController from AppDelegate

问题描述

当 APP 启动时 - 启动 SigninView - 没问题.接下来如果成功 - 我需要 showTripController().功能工作但没有显示?有什么问题?

When APP is Launching - start SigninView - it's Okey. Next if success - I need showTripController(). Function work but nothing show? What's a problem?

func showSigninView() {
    let controller = self.window?.rootViewController!.storyboard?.instantiateViewControllerWithIdentifier("DRVAuthorizationViewController")
    self.window?.rootViewController!.presentViewController(controller!, animated: true, completion: nil)
}

func showTripController() {
    let cv = self.window?.rootViewController!.storyboard?.instantiateViewControllerWithIdentifier("DRVTripTableViewController")
    let nc = UINavigationController()
    self.window?.rootViewController!.presentViewController(nc, animated:true, completion: nil)
    nc.pushViewController(cv!, animated: true);
}

推荐答案

首先你必须在使用 window 之前添加这个:

First of all you must add this before you use window :

self.window.makeKeyAndVisible()

还有一点要记住:

有时 keyWindow 可能已被 window 替换为 nil rootViewController(在 iPhone 上显示 UIAlertViews、UIActionSheets 等)，在这种情况下，您应该使用 UIView 的 window 属性.

因此，不要使用 rootViewController，而是使用它提供的最上面的一个:

So, instead of using rootViewController, use the top one presented by it:

extension UIApplication {
    class func topViewController(base: UIViewController? = UIApplication.sharedApplication().keyWindow?.rootViewController) -> UIViewController? {
        if let nav = base as? UINavigationController {
            return topViewController(base: nav.visibleViewController)
        }
        if let tab = base as? UITabBarController {
            if let selected = tab.selectedViewController {
                return topViewController(base: selected)
            }
        }
        if let presented = base?.presentedViewController {
            return topViewController(base: presented)
        }
        return base
    }
}

if let topController = UIApplication.topViewController() {
    topController.presentViewController(vc, animated: true, completion: nil)
}

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