Disabling setting - .setDisabled() does not seem to be working

I am trying to disable a text entry setting if the preceeding setting does not require its value.

.setDisabled() does not seem to be working

Also I cannot seem to access the whole settings control div element. That in the main settings “Files and links” > “Default location for new attachments”, “Attachment folder path” has its div add a `style:=“display: none;”.

const texImageDirectorySetting = new Setting(containerEl)
  .setName('TeX Image Directory')
  .setDesc('Where to save rendered TeX images')
  .addDropdown(dropdown => dropdown
    .addOption('vault', 'Vault Root')
    .addOption('vault-subdirectory', 'Vault Sub directory')
    .addOption('obsidian', 'Obsidian Directory')
    .addOption('current', 'Current Markdown directory')
    .addOption('subdirectory', 'Markdown Sub directory')
    .setValue(this.plugin.settings.texImageDirectory || 'vault')
    .onChange(async (value) => {
      this.plugin.settings.texImageDirectory = value;
      await this.plugin.saveSettings();
      (<HTMLElement>subdirectorySetting.controlEl.parentNode).setAttribute("style", value == 'subdirectory' || value == 'vault-subdirectory' ? "" : "display: none;");
      //subdirectorySetting.setDisabled(this.plugin.settings.texImageDirectory == 'vault' || this.plugin.settings.texImageDirectory == 'obsidian')

const subdirectorySetting = new Setting(containerEl)
  .setDesc('Subdirectory relative to the Markdown file for storing images')
  .addText(text => text
    .setPlaceholder('Enter subdirectory name')
    //.setDisabled(this.plugin.settings.texImageDirectory == 'vault' || this.plugin.settings.texImageDirectory == 'obsidian')
    .onChange(async (value) => {
      this.plugin.settings.markdownAttachmentSubdirectory = value;
      await this.plugin.saveSettings();

I cannot seem to get the div element for the whole control setting’s div. The following is how I seem to be able to make is disappear :-

(subdirectorySetting.controlEl.parentNode).setAttribute(“style”, value == ‘subdirectory’ || value == ‘vault-subdirectory’ ? “” : “display: none;”);

neither :-

  • descEL
  • infoEl
  • controlEl

seem to access the setting’s div element.

Can someone put me straight on these issues or point me to an example plugin that shows how to do this please ?