在 jetpack compose 中启用/禁用 TextField 后如何管理 TextField 焦点？

Question

I am working with TextField, and I have faced some issues regarding focus.

Disabled all TextField, only the first one is enabled. When trying to enable other TextField, it lost focus, how we can get back focus? Screenshot_20220602_121247 Here is my layout:-

How to shift focus programmatically when enabling TextField?

Here is my code snippet which I have used to enable and disable the TextField.

fun enabledDisabledTextField(
enteredValues: MutableList<String>,
index: Int,
isEnabled: Boolean): Boolean {
var enabled = isEnabled

val isFirstTime = enteredValues[0].isEmpty()

if (isFirstTime) {
    if (enteredValues[index].isEmpty()) {
        if (index == 0) {
            enabled = true
        }

        if (index > 0) {
            enabled = false
        }
    }
} else {
    if (enteredValues[index].isEmpty()) {
        enabled = true
    }
    if (enteredValues[index].isNotEmpty()) {
        enabled = false
    }
    if (index == enteredValues.size - 1) {
        enabled = true
    }
}
return enabled

}

Answer 1

I haven't tried to experiment this code yet when dealing with focus management, but there's a function exposed by Modifier where you can manage some focus properties, though I'm not quite sure if this would work and if you need to explicitly supply a FocusRequster object on each of the Box 's child

 val focusRequester = remember { FocusRequester.Default }

    Box(modifier = Modifier
        .focusProperties {
            // you might be able to switch focus here
            this.next.requestFocus()
        }
    ) {

        // your text field 1
        TextField(
            modifier = Modifier
                .focusRequester(focusRequester)
        )

        // your text field 2
        TextField(
            modifier = Modifier
                .focusRequester(focusRequester)
        )

        // your text field 3
        TextField(
            modifier = Modifier
                .focusRequester(focusRequester)
        )
    }

FocusManager also provides some convenience with its moveFocus function

val focusManager = LocalFocusManager.current
focusManager.moveFocus(FocusDirection.Next)
    //or
focusManager.moveFocus(FocusDirection.Right)

Guessing your code/logic, call a focusRequester supplied on a textfield's Modifier , again I'm not sure if you have to create a list of FocusRequester and each of them will be supplied to each of your TextField

SideEffect {
        // I'm assuming some validation will run regarding the enabling of a textfield of yours
        if (someStateHandler[index].shouldBeEnabled) {
            focusRequester.requestFocus()
        }
    }