core/misc/announce.js


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/**
* DO NOT EDIT THIS FILE.
* See the following change record for more information,
* https://www.drupal.org/node/2815083
* @preserve
**/

(function (Drupal, debounce) {
  let liveElement;
  const announcements = [];
  Drupal.behaviors.drupalAnnounce = {
    attach(context) {
      if (!liveElement) {
        liveElement = document.createElement('div');
        liveElement.id = 'drupal-live-announce';
        liveElement.className = 'visually-hidden';
        liveElement.setAttribute('aria-live', 'polite');
        liveElement.setAttribute('aria-busy', 'false');
        document.body.appendChild(liveElement);
      }
    }

  };

  function announce() {
    const text = [];
    let priority = 'polite';
    let announcement;
    const il = announcements.length;

    for (let i = 0; i < il; i++) {
      announcement = announcements.pop();
      text.unshift(announcement.text);

      if (announcement.priority === 'assertive') {
        priority = 'assertive';
      }
    }

    if (text.length) {
      liveElement.innerHTML = '';
      liveElement.setAttribute('aria-busy', 'true');
      liveElement.setAttribute('aria-live', priority);
      liveElement.innerHTML = text.join('\n');
      liveElement.setAttribute('aria-busy', 'false');
    }
  }

  Drupal.announce = function (text, priority) {
    announcements.push({
      text,
      priority
    });
    return debounce(announce, 200)();
  };
})(Drupal, Drupal.debounce);