Switch case within switch case in Swift

Question

I have a Swift grammar question. I have a switch case in the function, and I need to make a nested switch case something like below.

func changeIcon(status: String){
    switch status {
    case "ready", "recording", "finished", "error":
        if indicator.isAnimating {
            indicator.stopAnimating()
            indicator.hidesWhenStopped = true
        }
        indicator.isHidden = true
        symbolImageView.isHidden = false
        
        switch status{
        case "ready":
            symbolImageView.image = Images.streamIsReady
        case "recording":
            symbolImageView.image = Images.streamIsOngoing
        case "finished":
            symbolImageView.image = Images.close
        case "error":
            symbolImageView.image = Image.error
        default:
            print("default")
        }
        
    case "init":
        symbolImageView.isHidden = true
        indicator.isHidden = false
        indicator.startAnimating()
    
    default:
        print("default")
    }
}

I want to use a switch case (or if statement is also fine if it's possible) for checking if I display UIimage or UIActivityIndicator, and then use another switch case to determine which UIImage should I display. I was wondering if using a nested switch case is redundant and there is an alternative way to achieve the same thing.

Answer 1

You could add a function, for example

func changeIcon(status: String) {
    switch status{
    case "ready":
        updateImage(.streamIsReady)
    case "recording":
        updateImage(.streamIsOngoing)
    case "finished":
        updateImage(.close)
    case "error":
        updateImage(.error)
        
    case "init":
        symbolImageView.isHidden = true
        indicator.isHidden = false
        indicator.startAnimating()
        
    default:
        print("default")
    }
}

func updateImage(_ image : Images){
    if indicator.isAnimating {
        indicator.stopAnimating()
        indicator.hidesWhenStopped = true
    }
    indicator.isHidden = true
    symbolImageView.isHidden = false
    symbolImageView.image = image
}

And I agree with Sulthan: Use an enum rather than a String

Answer 2

First of all, you should have an enum:

enum Status: String {
   // "init" renamed to "loading"
   case loading, ready, recording, finished, error

   var icon: UIImage? {
       switch self {
       case .loading:
           return nil
       case .ready:
           return Images.streamIsReady
       case .recording:
           return Images.streamIsOngoing
       case .finished:
           return Images.close
       case .error:
           return Image.error
       }
   }
}

Then your code can become:

func changeIcon(status: Status) {
    if status == .loading {
       indicator.startAnimating()
    } else {
       indicator.stopAnimating()
    }

    let icon = status.icon
    symbolImageView.isHidden = icon == nil
    symbolImageView.image = icon
}

Statement indicator.hidesWhenStopped = true should be part of your view setup and not inside this function.