任意格式化手机号、银行卡号

废话不说，直接上代码

import android.text.Editable
import android.text.Selection
import android.text.TextWatcher
import android.widget.EditText

open class FormatTextWatcher
@JvmOverloads
constructor(
    private val editText: EditText?,
    private val separatorSizes: IntArray,
    private val separator: String = " ",
    private val maxLength: Int = -1,
) : TextWatcher {
    /**
     * 是否正在格式化
     */
    private var isFormatting = false
    override fun beforeTextChanged(s: CharSequence, start: Int, count: Int, after: Int) {
    }

    @Synchronized
    override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
        if (isFormatting) {
            return
        }
        val plainNumber = s.toString().replace(separator.toRegex(), "")
        val text = formatNumber(plainNumber, separatorSizes, maxLength)
        isFormatting = true
        editText?.setText(text)
        isFormatting = false
    }

    override fun afterTextChanged(s: Editable) {
        Selection.setSelection(s, s.length)
    }

    private fun formatNumber(
        value: CharSequence,
        separatorSizes: IntArray,
        maxLength: Int
    ): CharSequence {
        val formattedNumber = StringBuilder()
        var segmentCount = 0 // 记录当前段已添加的字符数量。
        var segmentIndex = 0 // 当前段的位置
        val length = if (maxLength in 1..<value.length) {
            maxLength
        } else {
            value.length
        }
        for (i in 0 until length) {
            formattedNumber.append(value[i])
            segmentCount++
            if (segmentCount == separatorSizes[segmentIndex] && i + 1 < length && segmentIndex < separatorSizes.size - 1) {
                formattedNumber.append(' ')
                segmentCount = 0
                segmentIndex++
            }
        }
        return formattedNumber.toString()
    }

    companion object {

        @JvmStatic
        val PHONE = intArrayOf(3, 4, 4)

        @JvmStatic
        val CARD_CODE = intArrayOf(4, 4, 4, 3)

        @JvmOverloads
        @JvmStatic
        fun formatPhone(
            editText: EditText?,
            separator: String = " ",
            maxLength: Int = 11
        ) {
            editText?.addTextChangedListener(
                FormatTextWatcher(
                    editText,
                    PHONE,
                    separator,
                    maxLength
                )
            )
        }

        @JvmOverloads
        @JvmStatic
        fun formatCardCode(
            editText: EditText?,
            separator: String = " ",
            maxLength: Int = 19
        ) {
            editText?.addTextChangedListener(
                FormatTextWatcher(
                    editText,
                    CARD_CODE,
                    separator,
                    maxLength
                )
            )
        }

        @JvmOverloads
        @JvmStatic
        fun format(
            editText: EditText?,
            separatorSizes: IntArray,
            separator: String = " ",
            maxLength: Int = -1,
        ) {
            editText?.addTextChangedListener(
                FormatTextWatcher(
                    editText,
                    separatorSizes,
                    separator,
                    maxLength
                )
            )
        }
    }

}