No exact matches in call to instance method 'append'

Asked 1 years ago, Updated 1 years ago, 518 views

In swiftui

When I try to append from another screen to another screen

No exact matches in call to instance method 'append'

and

Value of type 'TextEditor' has no member 'text'

The alert appears.

Can't I use append?

Also, does the TextEditor not have text?

ContentView().array.append(textEditor.text)

says .

swiftui

2022-11-15 09:45

1 Answers

No exact matches in call to instance method 'append'

I don't have any proof, but if you replace textEditor.text in ContentView().array.append(textEditor.text) with "Sample", or String type literal, this message will probably disappear.There is no guarantee that the textEditor.text type is the String type, so the nuance is that the type does not match.However, even if the error persists, it has nothing to do with the nature of the problem.

Also, does the TextEditor not have text?

No, I don't have any.

Apple Developer Documentation Structure TextEditor

This page and the properties in the link View Implementations within this page are all the properties that the TextEditor has.There are no properties anywhere else that are not in these two locations.
This Apple Developer Documentation comes with Xcode as well as Apple's site.If you have any questions, I think you'll get a lot better at your work and study if you first get into the habit of researching the Apple Developer Documentation.

●So how can a program receive the string you entered in TextEditor?
The most important thing is that the idea doesn't fit in with the basic concept of SwiftUI.Avoid structures that involve GUI (Graphic User Interface) components at the core of the program.If you make any changes to the GUI configuration, the entire program should not be stopped.That's the basic concept of SwiftUI.

Write a simple program using TextEditor.

import SwiftUI

struct ContentView:View {
    
    @State var myText="
    
    varbody:someView {
        VStack {
            TextEditor (text:$myText)
                .padding()
            Text (myText)
        }
    }
}

TextEditor initiators must have String type properties marked with @State or @Binding.You cannot create an instance without that argument.In the code above, the property myText is substituted for the argument with $.
In this way, the user's input to TextEditor changes the value of the property myText in real time.You can see that Text that displays myText changes with each type.
From the above, since the value of the string entered in TextEditor is the same in real time as the property specified in the argument of the Initiator of TextEditor, the property can be obtained by accessing it.You'll find out.

In addition, you can see that ContentView().array access to the property array is also contrary to the SwiftUI style, and ContentView is only one part of the GUI.
(In addition, ContentView() also raises the question of what you want to do by creating a new instance that is different from the existing ContentView.)

Finally, if you enter any string on the modal screen, the list on the original screen will be displayed with the addition of the string you entered.
This sample code intentionally uses TextField instead of TextEditor.That's to give SwiftUI a hands-on experience of how GUI changes don't affect the fundamentals of the program. Replacing TextField with TextEditor would be interesting to try.

import SwiftUI

struct ContentView:View {
    
    @State var myArray=["Sunday", "Monday", "Tuesday"]
    @State var showModal=false
    
    varbody:someView {
        VStack {
            List(myArray,id:\.self){weekName in
                Text(weekName)
            }
                .padding()
            Button("Add an Item") {
                self.showModal.toggle()
            }.sheet(isPresented:$showModal){
                ModalView (isActive: $showModal, myArray: $myArray)
            }
        }
    }
}

structureModalView:View {
    @Binding var isActive:Bool
    @Binding var myArray: [String]
    
    @State private var newName=""
    
    varbody:someView {
        VStack {
            Text("Input a new name.")
                .padding()
            TextField("New Name", text:$newName)
            Button("Dismiss") {
                myArray.append(newName)
                isActive.toggle()
            }
        }
    }
}

@available (iOS 15.0, *)
structureContentView_Previews:PreviewProvider{
    static var previews:someView {
        ContentView()
            .previewInterfaceOrientation (.portrait)
    }
}


2022-11-16 02:13

If you have any answers or tips


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