SwiftUI Clear Textfield FirstResponder

Question

I'm looking to clear my FirstResponder TextField with an independent button that will save the field data and clear the input content so that we can write again. My code is based on the work of :

Matteo Pacini -> https://stackoverflow.com/a/56508132/15763454

The Clear variable should when it goes to True clear the field, it works when I click the button but I have to additionally enter a character in the text field for it to clear. This is logical since the "textFieldDidChangeSelection" function only runs when the textfield is changed

How can I make sure that as soon as my Clear variable changes to True the textfield is automatically deleted?

struct ContentView : View {
    
    @State var text: String = ""
    @State var Clear = false
    
    var body: some View {
        
        HStack{
            
            Spacer()
            
            Button(action: set,label: {
                Text("Clic")
            })
            
            
            Spacer()
            CustomTextField(text: $text,clear: $Clear,isFirstResponder: true)
                .frame(width: 300, height: 50)
                .background(Color.red)
        }
        
    }
    
    func set(){
        self.Clear=true
    }
    
}

struct CustomTextField: UIViewRepresentable {
    
    
    class Coordinator: NSObject, UITextFieldDelegate {
        
        @Binding var text: String
        @Binding var clear: Bool
        var didBecomeFirstResponder = false
        
        init(text: Binding<String>,clear: Binding<Bool>) {
            _text = text
            _clear = clear
            
        }
        
        func textFieldDidChangeSelection(_ textField: UITextField) {
            text = textField.text ?? ""
            if clear == true{
                textField.text?.removeAll()
                clear = false
            }
        }
        
    }
    
    
    @Binding var text: String
    @Binding var clear: Bool
    var isFirstResponder = false
    
    func makeUIView(context: UIViewRepresentableContext<CustomTextField>) -> UITextField {
        let textField = UITextField(frame: .zero)
        textField.delegate = context.coordinator
        return textField
    }
    
    func makeCoordinator() -> CustomTextField.Coordinator {
        return Coordinator(text: $text,clear: $clear)
    }
    
    func updateUIView(_ uiView: UITextField, context: UIViewRepresentableContext<CustomTextField>) {
        uiView.text = text
        if isFirstResponder && !context.coordinator.didBecomeFirstResponder  {
            uiView.becomeFirstResponder()
            context.coordinator.didBecomeFirstResponder = true
        }
    }
}

score 1 · Answer 1 · answered Apr 25 '21 at 22:29

1

Just replace

func set() {
    self.Clear=true
}

with

func set() {
    self.text = ""
}

This immediately clears the text.

answered Apr 25 '21 at 22:29

aheze

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it was so simple... Thanks a lot for your help, but using this solution I have a non-blocking conflict in xcode "Modifying state during view update, this will cause undefined behavior." Do you think this is disturbing for the next step? – MaxLand Apr 26 '21 at 13:13
@MaxLand yeah, you should avoid that. I don't get the error with the code that you posted, maybe it's somewhere else? Can you show the line of code that gets the error? – aheze Apr 26 '21 at 15:11
The problem happens when I click on the button, with the modification you indicated, the text field is well deleted but at the level of the line of code : text = textField.text ? "", the error : "Modifying state during view update, this will cause undefined behavior." appears. The error occurs on the Thread 1 visibly. – MaxLand Apr 26 '21 at 17:00
@MaxLand oh just get rid of the entire `textFieldDidChangeSelection method` – aheze Apr 26 '21 at 17:04
@MaxLand you can remove all references to `clear` too – aheze Apr 26 '21 at 17:05

SwiftUI Clear Textfield FirstResponder

1 Answers1