金额小数点后面和前面字体大小不一致的实现

核心代码：

 SpannableStringBuilder builder = new SpannableStringBuilder(amount);
        builder.setSpan(new AbsoluteSizeSpan(UIUtils.sp2px(12)), amount.indexOf("￥"), amount.indexOf("￥") + 1
, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
        builder.setSpan(new AbsoluteSizeSpan(UIUtils.sp2px(12)), amount.indexOf("."), amount.length()
, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
        activityRef.get().mBinding.allPrice.setText(builder);