colorizing passwords

passwords.scala

    sealed trait CharType
    case object Uppercase extends CharType
    case object Lowercase extends CharType
    case object Symbol extends CharType
    case object Digit extends CharType
    case class Spans(chartype: CharType, start: Int, end: Int)
    if (Option(strings.Get(PwDefs.PasswordField)) exists (_.Length > 0)) {
      val passfield = new StandardFieldView(this)
      passfield.first = first
      first = false
      passfield.hint = "Password"
      passfield.text = Database.getField(entry, PwDefs.PasswordField).fold("": CharSequence) { p =>
        val (spans,last) = p.zipWithIndex.foldLeft((List.empty[Spans],Spans(Lowercase, 0, 0))) { case ((a,span), (c,i)) =>
          val chartype = if (c.isDigit) Digit
          else if (c.isLower) Lowercase
          else if (c.isUpper) Uppercase
          else Symbol
          if (span.chartype == chartype) {
            (a,span)
          } else {
            (span.copy(end = i) :: a,Spans(chartype, i, i))
          }
        }
        val s = new SpannableString(p)
        (last.copy(end = p.length) :: spans).foreach { span =>
          if (span.end > 0) {
            val fg = span.chartype match {
              case Uppercase => new ForegroundColorSpan(0xffff0000)
              case Lowercase => new ForegroundColorSpan(0xff00ffff)
              case Symbol => new ForegroundColorSpan(0xff0000ff)
              case Digit => new ForegroundColorSpan(0xff00ff00)
            }
            s.setSpan(fg, span.start, span.end, Spanned.SPAN_INCLUSIVE_EXCLUSIVE)
          }
        }
        s
      }
      passfield.icon = R.drawable.ic_lock_outline_black_36dp
      passfield.password = true
      fieldlist.addView(passfield)
    }