Articles with predefined Tag List

/**
     * Gets the possible tags from the preList Tpl chunk and, if not empty,
     * injects the HTML and JS code to let user add tags by clicking on the buttons
     */
    protected function setTags() {
        $tags = '';
        $tagChunkName = $this->modx->getOption('prefListChunkName', $this->props, 'sbsPrefListTpl');
        $tagList = $this->modx->getChunk($tagChunkName);
        if (!empty($tagList)) {

            $src = '<script type="text/javascript">
function nf_insert_tag(tag) {
    var text = document.getElementById("nf_tags").value;
    if (text.indexOf(tag) != -1) {
       text= text.replace("," + tag + ",","," );
       text = text.replace(tag + ",","");
       text = text.replace("," + tag,"");
       text = text.replace(tag,"");
    } else {
        if (text) {
        text = text + "," + tag;
        } else {
          text = tag;
        }
    }
    var tagArray = text.split(",");
    tagArray.sort();
    text = tagArray.join(",");
    document.getElementById("nf_tags").value = text;
return false;
    }
</script>';

            $this->modx->regClientStartupScript($src);
            $tags = '<p>';
            $tagArray = explode('||', $tagList);
            natcasesort($tagArray);
            $i = 0;
            foreach ($tagArray as $t) {
                $t = strtolower($t);
                $pos = strpos($t, '==');
                $tag = $pos ? substr($t, $pos + 2) : $t;
                $tag = trim($tag);
                $tags .= '<button name="button' . $i . '" id="button' . $i .
                      '" type="button" class="nf_tag" onclick="nf_insert_tag(' .
                       "'" . $tag . "'" . ');"' . '">' . $tag . "</button>\n";
                $i++;
            }
            $tags .= '</p>';
        }
        $this->modx->setPlaceholder('nf_tag_list', $tags);
    }