Jetpack Compose：向 BasicTextField 添加字符计数器

Question

I am trying to add a character counter inside a BasicTextField (I cant use TextField. It has to be below the Material level). I added a BasicText in the decorator but now I need to update it whenever someone changes the text. How do I get the text string from the innerTextField and update my BasicText?

@Composable
fun MyTextField(
    value: TextFieldValue,
    onValueChange: (TextFieldValue) -> Unit,
    modifier: Modifier = Modifier
){
    val charCount = 0 // How do I update this in onValueChange?

    BasicTextField(
        value = value,
        onValueChange = onValueChange,
        modifier = modifier,
        decorationBox = { innerTextField ->
            Row(
                Modifier
                    .padding(16.dp)
            ) {
                BasicText(text = charCount.toString())
                Spacer(Modifier.width(5.dp))
                innerTextField()
            }
        })
}

Answer 1

You can simply use val charCount = value.text.count() . It will always be up to date thanks to recomposition happening automatically.