SwiftUI TextFields based on #Published array not updating - swiftui

Question

I am trying to lay out a bunch of CustomTextViews which can toggle between a SwiftUI TextField or Text view.
Consider this example.
import SwiftUI
struct ContentView: View {
#StateObject var doc: Document = Document()
var body: some View {
ForEach(doc.lines, id: \.self) { line in
HStack {
ForEach(line, id: \.self) { word in
CustomTextView(text: word, document: doc)
.fixedSize()
}
Spacer()
}
}
.frame(width: 300, height: 300)
.background(.cyan)
}
}
struct CustomTextView: View {
#State var text: String
#State var isEditing: Bool = false
#ObservedObject var document: Document
var body: some View {
if isEditing {
TextField("", text: $text)
.onSubmit {
isEditing.toggle()
// NOTE: reset document anytime a word ends in "?"
if text.last! == "?" {
print("resetting")
document.lines = [["Reset"]]
print(document.lines)
}
}
} else {
Text(text)
.onTapGesture {
isEditing.toggle()
}
}
}
}
class Document: ObservableObject {
#Published var lines: [[String]] = [["Hello"]]
}
What I want to happen is that I should be able to indefinitely reset the text. But instead, the view only resets correctly once (see gif). All further updates to reset document.lines are not correct, even though the print statements show that the #Published property lines is clearly changing.
What am I doing wrong?

Answer 1

You need to update the textfield text with document.lines[index] where index is index of line into document.lines array. So you need to update like below.
struct CustomTextView: View {
#State var isEditing: Bool = false
#ObservedObject var document: Document
var body: some View {
if isEditing {
TextField("", text: $document.lines[index])
.onSubmit {
isEditing.toggle()
// NOTE: reset document anytime a word ends in "?"
if document.lines[index].last! == "?" {
print("resetting")
document.lines = [["Reset"]]
print(document.lines)
}
}
} else {
Text(text)
.onTapGesture {
isEditing.toggle()
}
}
}
}