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iOS

Posted by James McMillan
James McMillan
9,787 Points

Cannot assign value of type '(String)' -> Page' to type 'Page?'

Working on the new InteractiveStory lesson I get this error when trying to build the app to run in the simulator the error is in the ViewController.swift file. I cannot figure out what I have done wrong. Here is the snippet of code where the error is raised:

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "startAdventure" {
            if let pageController = segue.destinationViewController as? PageController {
                pageController.page = Adventure.story  // <<<Cannot assign value of type '(String)' -> Page' to type 'Page?'
            }
        }
}
Greg Kaleka
Greg Kaleka
39,021 Points

Hi James,

Can you also paste in the code from your Adventure struct? I think the problem is probably there, specifically in your declaration of the story property.

Just hit Add Comment, and then paste your code in between coding tags like this:

```Adventure.swift

[paste your code in here]

```

James McMillan
James McMillan
9,787 Points

Thanks Greg for the quick response!

here is the code.

Adventure.swift 
struct Adventure {
    static func story(name: String) -> Page {
        let returnTrip = Page(story: .ReturnTrip)
        let touchdown = returnTrip.addChoice("Stop and Investigate", story: .TouchDown)
        let homeward = returnTrip.addChoice("Continue Home to Earth", story: .Homeward)
        let rover = touchdown.addChoice("Explore the Rover", story: .Rover)
        let crate = touchdown.addChoice("Open the Crate", story: .Crate)

        homeward.addChoice("Head back to Mars", page: touchdown)
        let home = homeward.addChoice("Continue Home to Earth", story: .Home)

        let cave = rover.addChoice("Explore the Coordinates", story: .Cave)
        rover.addChoice("Return to Earth", page: home)

        cave.addChoice("Continue towards faint light", story: .Droid)
        cave.addChoice("Refill the ship and explore the rover", page: rover)

        crate.addChoice("Explore the Rover", page: rover)
        crate.addChoice("Use the key", story: .Monster)

        return returnTrip
    }
}

1 Answer

James McMillan
James McMillan
9,787 Points
James McMillan
James McMillan
9,787 Points

I see what I did wrong. the it should be

static var story: Page

instead of

static func story(name: String) -> Page {

changed that line and everything works better now!

thanks for pointing me to the right place to look.

Greg Kaleka
Greg Kaleka
39,021 Points

Yep bingo. Computed property, not method :).

Glad you figured it out!