问如何使用Android SpannableString和MaskFilterSpan来像预期的那样模糊来自TextView的一些文本？

EN

private void testBlurText() {
    String text = "Alec Baldwin nailed his job; \n" +
            "The animators nailed their job (seriously, the art style and changes were amazing);\n" +
            "The ideas guy nailed his job ([spoiler]It's all the imagination of the kid[/spoiler]);\n" +
            "The writers just let the story down :( ([spoiler]Although at the beginning it's clear that the whole shebang is the older kid's imagination, the writers probably realised that the script was too short and so the end got changed to something that makes no sense. Why would Tim receive the kid for a second time? - unless it was all a dream...[/spoiler] ).\n" +
            "\n" +
            "All in all, a good movie, amazing acting and animating, partly let down by a badly written ending to the story. 8/10.";
    SpannableString spanText = new SpannableString(text);
    List<Pair<Integer, Integer>> spoilersContainer = new ArrayList<>();
    getSpoilerIndex(text, 0, spoilersContainer);
    for (Pair<Integer, Integer> pair : spoilersContainer) {
        spanText.setSpan(new MaskFilterSpan(new BlurMaskFilter(20, BlurMaskFilter.Blur.NORMAL)), pair.first, pair.second, Spanned.SPAN_INCLUSIVE_INCLUSIVE);
        Logger.d("SpoilerIndex:" + pair.toString());
    }
    tvTestBlurText.setText(spanText);
}

private void getSpoilerIndex(String rawComment, int beginIndex, List<Pair<Integer, Integer>> spoilersContainer) {
    int startIndex = rawComment.indexOf("[spoiler]", beginIndex);
    int endIndex = rawComment.indexOf("[/spoiler]", beginIndex);
    if (startIndex != -1 && endIndex != -1) {
        spoilersContainer.add(new Pair<>(startIndex, endIndex + "[/spoiler]".length()));
        getSpoilerIndex(rawComment, endIndex + "[/spoiler]".length(), spoilersContainer);
    }
}