UIApplicationShortcutItem in didFinishLaunching - ios

Question

According to Apple documentation :
It’s your responsibility to ensure the system calls this method conditionally, depending on whether or not one of your app launch
methods (application:willFinishLaunchingWithOptions: or
application:didFinishLaunchingWithOptions:) has already handled a
quick action invocation. The system calls a launch method (before
calling this method) when a user selects a quick action for your app
and your app launches instead of activating. The requested quick
action might employ code paths different than those used otherwise
when your app launches. For example, say your app normally launches to
display view A, but your app was launched in response to a quick
action that needs view B. To handle such cases, check, on launch,
whether your app is being launched via a quick action. Perform this
check in your application:willFinishLaunchingWithOptions: or
application:didFinishLaunchingWithOptions: method by checking for the
UIApplicationLaunchOptionsShortcutItemKey launch option key. The
UIApplicationShortcutItem object is available as the value of the
launch option key.
But why there is a need to handle this in didfinishlauncing/willfinishLauncing methods. If the app is in killed state, eventually it will call the performActionForShortcutItem method, so why there is a need to check in didfinish method?
Sample code:
//code
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
var launchedFromShortCut = false
//Check for ShortCutItem
if let shortcutItem = launchOptions?[UIApplicationLaunchOptionsShortcutItemKey] as? UIApplicationShortcutItem {
launchedFromShortCut = true
handleShortCutItem(shortcutItem)
}
//Return false incase application was lanched from shorcut to prevent
//application(_:performActionForShortcutItem:completionHandler:) from being called
return !launchedFromShortCut
}
func application(application: UIApplication, performActionForShortcutItem shortcutItem: UIApplicationShortcutItem, completionHandler: Bool -> Void) {
let handledShortCutItem = handleShortCutItem(shortcutItem)
completionHandler(handledShortCutItem)
}
func handleShortCutItem(shortcutItem: UIApplicationShortcutItem) -> Bool {
var handled = false
//Get type string from shortcutItem
if let shortcutType = ShortcutType.init(rawValue: shortcutItem.type) {
//Get root navigation viewcontroller and its first controller
let rootNavigationViewController = window!.rootViewController as? UINavigationController
let rootViewController = rootNavigationViewController?.viewControllers.first as UIViewController?
//Pop to root view controller so that approperiete segue can be performed
rootNavigationViewController?.popToRootViewControllerAnimated(false)
switch shortcutType {
case .Torquiose:
rootViewController?.performSegueWithIdentifier(toTurquoiseSeque, sender: nil)
handled = true
case.Red:
rootViewController?.performSegueWithIdentifier(toRedSeque, sender: nil)
handled = true
}
}
return handled
}
}

Answer 1

It gives you the flexibility to decide - you can handle it "early" in didFinishLaunching - returning FALSE will inhibit performActionForShortcutItem from getting called later. Or you can return TRUE in didFinishLaunching, and performActionForShortcutItem will still get called.