How Can I change text display in textfiled aftere editing finished in swiftui

Question

example

if focus in textfield will display text (number normal)

if not focus textfield will display x in 3 fist digit

e.g.

• textfield focus user type 123456
• textfield not focus textfield will display xxx456
• textfield focus again will display 123456

Answer 1

You need to associate a FocusState with the field and then respond to changes in focus. See the answer to How to detect when a TextField loses the focus in SwiftUI for iOS? for more about FocusState.

Here is an example of how it could work:

struct ContentView: View {
    @FocusState private var isFocused: Bool
    @State private var masterText = ""
    @State private var visibleText = ""

    var body: some View {
        Form {
            Section {
                TextField("Secret number", text: $visibleText)
                    .focused($isFocused)
                    .onChange(of: isFocused) { isFocused in
                        if isFocused {
                            visibleText = masterText
                        } else {
                            masterText = visibleText
                            if !visibleText.isEmpty {
                                let endRange = min(visibleText.count, 3)
                                let endOfString = visibleText.dropFirst(endRange)
                                visibleText = "xxx" + endOfString
                            }
                        }
                    }
            }
            Section {
                TextField("Another field", text: .constant(""))
            }
        }
    }
}