• What is Shortcuts in iOS 12?
    • It is an assistant that can help user find and finish what he wants to do quickly, whether by displaying elements in lock screen, Siri or Shortcuts app
  • What is Shortcuts constructed by?
    • UserActivity that can be donated to show on lock screen, spotlight search, notification center, and user can tap to enter app, also can be trigger by Siri.
      • Intent that can be interacted with user by tap or Siri. Now you can even finish a task without open your app!
      • Shortcuts App(formally named Workflow): An app that can help user finish a group of tasks by click, and can be easily customized.
  • What can we do with shortcuts with UserActivity?
    • Donate shortcuts
      • New a UserActivity, and set need properties
        • Call becomeActive on the object and store it
          • iOS will learn automatically by current time, date, location and suggest this action for user later
      • Remove shortcuts
        • NInteraction.removeAll/removeWithId/removeWithIds
      • Respond to click of shortcuts
        • Add type for NSUserActivity in Info.plist
        • Implement in appdelegate 
          func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([Any]?) -> Void) -> Bool
        • Make a class that conform UIUserActivityRestoring protocol
          • Commonly it is your home viewController or app delegate
            • You can use navigator or router to route to specific viewControllers with info from userActivity’s userInfo which was donated by you
      • Suggest shortcuts to user, and user can find in setting
        • Use INVoiceShortcutCenter.shared.setShortcutSuggestions([INShortcut]) to suggest intents for user
        • Suggest user to immediately add voice phrase to a certain shortcut
        • Use INUIAddVoiceShortcutButton to show add to Siri button
        • Use system Controller INUIAddVoiceShortcutViewController to make user input voice phrase for certain shortcuts
      • Update added voice shortcut with new voice phrase
        • Use INUIEditVoiceShortcutViewController to make user update voice phrase for certain shortcuts
      • How to debug a shortcut
        • Setting -> Developer -> Shortcut testing
      • Show recently added shortcut
  • Problems
    • When get useractivity from INVoiceShortcut.INShortcut.userActivity, the persistentIdentifier is nil.
    • In this way, I can only distinct shortcuts by some values in the userInfo