字符串中数字的颜色的改变

/**
 * 设置字符串中的数字显示红色
 * @param str
 */
public static void setNumberTextColor(String str,TextView textView,Context c,int resourcesID){
    char[] s = str.toCharArray();
    SpannableString ss = new SpannableString(str);
    for (int i = 0; i < s.length; i++){
        if (isNum(String.valueOf(s[i]))){
            ss.setSpan(new ForegroundColorSpan(c.getResources().getColor(resourcesID)), i, i+1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
        }
    }
    textView.setText(ss);
}

/**
 * 判断是否是数字
 * @param str
 * @return
 */
private static boolean isNum(String str) {
    try {

        new BigDecimal(str);
        return true;
    } catch (Exception e) {
        return false;
    }
}