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iOS Build a Playlist Browser with Swift Refactoring Our Code Passing Playlist Objects Using Segues

erik davis
erik davis
7,632 Points
Posted by erik davis
erik davis
7,632 Points

the find function

I get an error when typing "if let index = find(playlistsArray, playlistImageView)" It says "'find' is unavailable: call the 'indexOf() method on the collection'" What does this mean?

1 Answer

Nathan Tallack
Nathan Tallack
22,158 Points
Nathan Tallack
Nathan Tallack
22,158 Points

Yeah, this is because Swift 2.0 does not support find() anymore.

Try the following code.

let playlistImageView = sender!.view as! UIImageView
if let index = playlistsArray.indexOf(playlistImageView) {}

Don't forget to force unwrap where required using the ! characters in the let statement before the if. Don't be frightened, the if let will make sure all is well. ;)

Nathan Tallack
Nathan Tallack
22,158 Points
Nathan Tallack
Nathan Tallack
22,158 Points

For some context. :)

// Swift 1.2
var word = "Apple"
var searchCharacter: Character = "p"

if contains(word.lowercaseString, searchCharacter) {
    print("word contains \(searchCharacter)")
}

if let index = find(word.lowercaseString, searchCharacter) {
    print("Index: \(index)")
}

// Swift 2
var word = "Apple"
var searchCharacter: Character = "p"

if word.lowercaseString.characters.contains(searchCharacter) {
    print("word contains \(searchCharacter)")
}

if let index = word.lowercaseString.characters.indexOf(searchCharacter) {
    print("Index: \(index)")
}