3D touch quick actions preview view controller only one time

Question

I have the following issue. When I run my app on my phone, 3d touch the icon and select the quick action it launches the app presenting the correct view controller but when I put the app in background and try to invoke the quick action it just opens the app where I have left it. So to make it work I have to kill my app every time. Here is my code:

func application(application: UIApplication, performActionForShortcutItem shortcutItem: UIApplicationShortcutItem, completionHandler: (Bool) -> Void) {
    if shortcutItem.type == "com.traning.Search" {

        let sb = UIStoryboard(name: "Main", bundle: nil)

        let searchVC = sb.instantiateViewControllerWithIdentifier("searchVC") as! UINavigationController

        let root = UIApplication.sharedApplication().keyWindow?.rootViewController
        root?.presentViewController(searchVC, animated: false, completion: { () -> Void in
            completionHandler(true)
        })

    }
}

Thanks in advance.

Where does it have to call the performActionForShortcutItem? — martin petrov, Dec 02 '15 at 18:33
I mean just try printing something in performActionForShortcutItem to ensure it's being called. Perhaps print(root) that why you can check if performActionForShortcutItem is called and check to make sure root is not nil. — beyowulf, Dec 02 '15 at 18:37
The problem is that it calls the method only once after I launch the app then if I put it in the background and try to call the method nothing happens. — martin petrov, Dec 02 '15 at 18:42
Do you know for a fact it's not calling it? Or might it get called but not do anything? Doing what I suggested will help us determine which it is. Do you do so? What was the result? — beyowulf, Dec 02 '15 at 18:44
So it calls it everytime but does not transfer to the correct view controller. — martin petrov, Dec 02 '15 at 18:46
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/96826/discussion-between-martin-petrov-and-beyowulf). — martin petrov, Dec 02 '15 at 18:51

beyowulf · Accepted Answer · 2015-12-02T20:15:45.443

I'm guessing you're trying to present a view controller from a view controller that's not visible. You can use extensions like:

    extension UIViewController {
    func topMostViewController() -> UIViewController {
        if self.presentedViewController == nil {
            return self
        }
        if let navigation = self.presentedViewController as? UINavigationController {
            return navigation.visibleViewController.topMostViewController()
        }
        if let tab = self.presentedViewController as? UITabBarController {
            if let selectedTab = tab.selectedViewController {
                return selectedTab.topMostViewController()
            }
            return tab.topMostViewController()
        }
        return self.presentedViewController!.topMostViewController()
    }
}

extension UIApplication {
    func topMostViewController() -> UIViewController? {
        return self.keyWindow?.rootViewController?.topMostViewController()
    }
}

You can place both of these in your app delegate.swift, above your app delegate class, to get the currently visible view controller. Then present the search view controller on that. For example:

func application(application: UIApplication, performActionForShortcutItem shortcutItem: UIApplicationShortcutItem, completionHandler: (Bool) -> Void) {
    if shortcutItem.type == "com.traning.Search" {

        let sb = UIStoryboard(name: "Main", bundle: nil)

        let searchVC = sb.instantiateViewControllerWithIdentifier("searchVC") as! UINavigationController

        let topViewController = UIApplication.sharedApplication.topMostViewController()
        topViewController.presentViewController(searchVC, animated: false, completion: { () -> Void in
            completionHandler(true)
        })

    }
}

Thanks but I still don't understand where to put that function and where to call it. — martin petrov, Dec 02 '15 at 19:10
It gives error on this line: extension UIViewController { Declaration is only valid at file scope — martin petrov, Dec 02 '15 at 20:11
Yeah, I was putting it after the @ApplicationMain. But even after I implemented the extensions as you showed, the func application is working only the first time after it is launched. The moment it goes to background it doesn't work anymore. — martin petrov, Dec 02 '15 at 20:33
My mistake it works now, I forgot to uncomment something. Thank you very very much!!! — martin petrov, Dec 02 '15 at 20:38
I would like to have 10 accounts and upvote this answer 10 times cuz it made my day after 2 days of searching for such a great answer, thank you sooo much — MBH, Feb 10 '16 at 19:41

3D touch quick actions preview view controller only one time

1 Answers1