EmojiExcludedEditText

class EmojiExcludedEditText : EditText {
  constructor(context: Context) : super(context) {
    init()
  }

  constructor(context: Context, attrs: AttributeSet) : super(context, attrs) {
    init()
  }

  constructor(context: Context, attrs: AttributeSet, defStyleAttr: Int) : super(context, attrs,
      defStyleAttr) {
    init()
  }

  private fun init() {
    filters = arrayOf<InputFilter>(EmojiExcludeFilter())
  }

  private inner class EmojiExcludeFilter : InputFilter {

    override fun filter(source: CharSequence, start: Int, end: Int, dest: Spanned, dstart: Int,
        dend: Int): CharSequence? {
      return if ((start..end - 1)
          .map { Character.getType(source[it]) }
          .any { it == Character.SURROGATE.toInt() || it == Character.OTHER_SYMBOL.toInt() }) "" else null
    }
  }
}