Question 130533 in Xcode Question posted in
Whether you're new to Xcode or an experienced developer, our archive has everything you need to know about this integrated development environment (IDE). From basic functionalities to advanced features, our archive covers a wide range of Xcode-related questions and answers. Browse our archive now and find solutions to your Xcode questions, and take your app development skills to the next level

Xcode – Getting a sub string from a string to show in Text for Swiftui

Greeting everyone. I just started my Swiftui journey.

I am trying to get a piece of string from a string variable to display as Text() in Swiftui. In my previous languages I would do something like var subVal = val[1] but it seem this method does not work here.

Is there a way to work around this problem?

//I want the "r" value which is the second element of val 
var val = "orange"
@State var newVal = val[1]

.....
Text("(newVal)"
Tags:

2

Answers


  1. Chosen as BEST ANSWER
    0

    There are many possible ways that you can extract a substring from a string either to get a Character or a new String by using .prefix, .suffix, .index, etc.

    var val = "orange"

//using prefix, you will receive a string back
var newVal = val.prefix(2) //"or"

//using suffix, you will receive a string back
var newVal = val.suffix(2) //"ge"

    for your case, you can either use the given solution by @workingdog support Ukraine or create a custom extension for reuse

    struct ContentView: View {
@State var val = "orange"
var body: some View {
    //you can do String[index] directly
    //the return value is Character, so you need to cast to String
    Text(String(val[1])) //"r"
}
}

//reusable extension
extension StringProtocol {
subscript(offset: Int) -> Character {
    self[index(startIndex, offsetBy: offset)]
}
}

  2. 0

    you should read the basics at: https://docs.swift.org/swift-book/LanguageGuide/TheBasics.html especially the section on Strings and Characters in Swift at: https://docs.swift.org/swift-book/LanguageGuide/StringsAndCharacters.html and also do the tutorial at: https://developer.apple.com/tutorials/swiftui/

    Without knowing the basics you will not go very far in coding your app.

    struct ContentView: View {
    var val = "orange"
    @State var newVal = ""
    
    var body: some View {
        Text(newVal)
            .onAppear {
                let index = val.index(val.startIndex, offsetBy: 1)
                newVal = String(val[index])
            }
    }
}
    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search