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iOS

Posted by Alexandre Perron
Alexandre Perron
4,410 Points

Swift Course Question - Segues

Hello all, this is my following code in "PlaylistMasterViewController.swift" while following the "Build a Playlist Browser App for iPhone" course.

import UIKit

class PlaylistMasterViewController: UIViewController {

@IBOutlet weak var aButton: UIButton!

override func viewDidLoad() {
    super.viewDidLoad()

    aButton.setTitle("Press Me!", forState: .Normal)
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "showPlaylistDetail" {
        let playlistDetailController = segue.destinationViewController as PlaylistDetailViewController
        playlistDetailController.segueLabelText = "Yay! You Pressed The Button"
    }
}}

on the "let playlistDetailController" line, it gives me the error "anyObject is not convertible to 'PlaylistDetailViewController'; did you mean to use as! to force downcast?"

I do not understand what this line means and how I can resolve this issue? Can a kind soul enlighten me?

Cheers, Alex

2 Answers

Jhoan Arango
Jhoan Arango
14,575 Points

Hello Alexandre:

The down casting is a whole different topic which you won’t find here in detail yet. But If you are curious about it I recommend reading one of the answers given to me a few months ago. Here is the link to it.

https://teamtreehouse.com/forum/downcasting-as-someone-please-pretend-i-m-5-years-old-and-explain-downcasting-and-why-should-we-use-it

Now, on your question... resolving the issue, Xcode gives you a suggestion that says “fix it”. It will help you solve your problem. In this case I think its best to use as! to downcast. That should solve your problem, but you may not understand it yet until you read more about down casting.

Hope this helps

Sherry Fleming
PLUS
Sherry Fleming
Courses Plus Student 6,680 Points
Sherry Fleming
Sherry Fleming
Courses Plus Student 6,680 Points

no it didn't - it allowed the code to at least compile, but the Detail view has no content- they need to update this course- the "Cocoa" template he had us start with wasn't even relevent