Ios 17 TextField Binding Issue

[Little-tale]

Description

From Swift UI to TCA
Failed to configure membership logic.
While configuring the logic of TextField for phone number configuration

I've confirmed that it works fine on iOS 16 and below, and it doesn't work from 17.

`
// SignUpFeature
case let .contactChanged(phones):

let clean = phones.filter { $0.isNumber }

let result = TextValid.TextValidate(phones, caseOf: .phoneNumber)

print("sss")
// // state.user.contact = phones
state.user.contact = formatPhoneNumber(clean)
state.contactValid = result
return .none

/// View
VStack (alignment: .leading) {
Text(Const.SignUpView.contact.title)
TextField(
Const.SignUpView.contact.placeHolder,
text: $store.user.contact.sending(.contactChanged)
)
.modifier(DefaultTextFieldViewModifier())
}
.padding(.horizontal, 30)
`

The code was configured as above.
However, contrary to expectations, TextField only reflects the value entered by the user and does not reflect the value that goes through my logic.

For testing, simply

state.contactValid = " NONE "
Even when you say that, NONE is reflected only in the beginning
After that, it's not reflected.

How do I solve this problem?

Checklist

• I have determined whether this bug is also reproducible in a vanilla SwiftUI project.
• If possible, I've reproduced the issue using the main branch of this package.
• This issue hasn't been addressed in an existing GitHub issue or discussion.

Expected behavior

No response

Actual behavior

No response

Steps to reproduce

No response

The Composable Architecture version information

1.10.4

Destination operating system

iOS 16, 17

Xcode version information

Xcode 15.3

Swift Compiler version information

No response

[mbrandonw]

Hi @Little-tale, this is not an issue with the library, but rather just how SwiftUI works. You cannot make modifications to the state powering a TextField binding in the willSet/didSet. SwiftUI will just ignore those changes.

This issue has come up a lot, so I recommend searching the discussions for possible workarounds. Here is is the most recent time that it came up.

Since this isn't an issue with the library I am going to convert it to a discussion. Please feel free to continue the conversation over there!