兼容21及以下版本
fun EditText.setHintImageSpan(hintTips: String?, drawable: Int) {
val draw = ContextCompat.getDrawable(context, drawable)
draw?.setBounds(0, 0, draw.intrinsicWidth, draw.intrinsicHeight)
val span = CenterAlignImageSpan(draw)
val spannableBuilder = SpannableStringBuilder()
spannableBuilder.append("* ").append(hintTips)
spannableBuilder.setSpan(span, 0, 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)
hint = spannableBuilder
}
