Android 编写视觉转型

我有一个课程，可以将文本转发到手机屏蔽，PHONE_MASK是 const val PHONE_MASK = "+7 (7__) ___-__-__" 当我在文本字段中输入第一个字符时，我的文本指针的位置不正确(鼠标不会移动到文本的结尾) 我认为问题就在这里 override fun originalToTransformed(offset: Int): Int 因为当我输入第一个字符时，ofset仍然是零值

import androidx.compose.ui.text.AnnotatedString
import androidx.compose.ui.text.input.OffsetMapping
import androidx.compose.ui.text.input.TransformedText
import androidx.compose.ui.text.input.VisualTransformation
import kotlin.math.absoluteValue

class PhoneMaskVisualTransformation(val mask: String, val maskedSymbol: Char = MASKED_SYMBOL) :
    VisualTransformation {
    companion object {
        const val MASKED_SYMBOL = '_'
    }

    private val specialSymbolsIndices = mask.indices.filter { mask[it] != maskedSymbol }

    override fun filter(text: AnnotatedString): TransformedText {
        var out = ""
        var maskIndex = 0
        text.forEach { char ->
            while (specialSymbolsIndices.contains(maskIndex)) {
                out += mask[maskIndex]
                maskIndex++
            }
            out += char
            maskIndex++
        }
        return TransformedText(AnnotatedString(out), offsetTranslator())
    }

    private fun offsetTranslator() = object : OffsetMapping {
        override fun originalToTransformed(offset: Int): Int {
            val offsetValue = offset.absoluteValue
            if (offsetValue == 0) return 0
            var numberOfHashtags = 0
            val masked = mask.takeWhile {
                if (it == maskedSymbol) numberOfHashtags++
                numberOfHashtags < offsetValue
            }
            return masked.length + 1
        }

        override fun transformedToOriginal(offset: Int): Int {
            return mask.take(offset.absoluteValue).count { it == maskedSymbol }
        }
    }
}