JavaScript Hook for Composer

Development
2

I suspect you want to follow an existing example.

The place to look, I suspect, is discourse/app/assets/javascripts/discourse/components/d-editor.js.es6 at f62b8990acb9ce4af8bfc67fc80dc0847177e458 · discourse/discourse · GitHub

Specifically:

  didInsertElement() {
    this._super(...arguments);

    const $editorInput = $(this.element.querySelector(".d-editor-input"));
    this._applyEmojiAutocomplete($editorInput);
    this._applyCategoryHashtagAutocomplete($editorInput);

And maybe take a look at:

  _applyCategoryHashtagAutocomplete() {
    const siteSettings = this.siteSettings;

    $(this.element.querySelector(".d-editor-input")).autocomplete({
      template: findRawTemplate("category-tag-autocomplete"),
      key: "#",
      afterComplete: () => this._focusTextArea(),
      transformComplete: obj => {
        return obj.text;
      },
      dataSource: term => {
        if (term.match(/\s/)) {
          return null;
        }
        return searchCategoryTag(term, siteSettings);
      },
      triggerRule: (textarea, opts) => {
        return categoryHashtagTriggerRule(textarea, opts);
      }
    });
  },

NB I’ve not exploited this myself, but that’s my guess.