Draft: Add nested dropdown
What does this MR do?
This MR adds nested dropdown functionality to the GitLab UI disclosure dropdown component, enabling dropdown items to have child items that appear in submenus.
Key Changes
New Components:
GlDisclosureDropdownItemNested- Renders items with predefined childrenGlDisclosureDropdownItemNestedCustom- Supports custom content via slots (search, multi-select, etc.)GlDisclosureDropdownContent- Extracted content rendering logic
Behavior:
- Desktop: Opens on hover, positions right/left of parent
- Mobile: Opens on click, overlays parent with back button
- Keyboard navigation (Right to open, Left to close, Up/Down to navigate)
- Only one nested dropdown open at a time
Implementation:
- Uses Floating UI for desktop positioning
- Portal-based rendering for proper z-index layering
- Parent dropdown manages nested state and closes all on hide
- Responsive design with mobile-specific styling
Screenshots or screen recordings
| Mouse | Keyboard | Mobile |
|---|---|---|
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Integrations
- GitLab: mr_url
- CustomersDot: mr_url
- Duo UI: mr_url
- Status Page: mr_url
- Docs: mr_url
- Switchboard: mr_url
Does this MR meet the acceptance criteria?
This checklist encourages the authors, reviewers, and maintainers of merge requests (MRs) to confirm changes were analyzed for conformity with the project's guidelines, security and accessibility.
Toggle the acceptance checklist
Conformity
- The “What does this MR do?” section in the MR description is filled out, explaining the reasons for and scope of the proposed changes, per “Say why not just what”.
- For example, if the MR is focused on usage guidelines, addressing accessibility challenges could be added in a separate MR.
- Relevant label(s) are applied to the MR.
- The MR is added to a milestone.
- Added the
~"component:*"label(s) if applicable. - A changeset is added when this MR will do a patch, minor, or major update. More information can be found in
doc/publishing-packages.md.
Components
- GitLab UI's contributing guidelines.
- If the MR changes a component's API, integration MR(s) have been opened (see integrations above).
Documentation
- If creating a new component page from scratch, it follows the page template structure.
- Content follows the Pajamas voice and tone guidelines, falling back on the GitLab Documentation Style Guide when needed.
- Related pages are cross-linked, where helpful. Component pages have related components and patterns defined in their Markdown front matter.
- If embedding a Figma file, it follows the Figma embed guide.
- Review requested from any GitLab designer or directly from a maintainer or trainee maintainer.
- Maintainer review follows the Pajamas UX maintainer review checklist.
Security
If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:
- Label as security and @ mention
@gitlab-com/gl-security/appsec - Security reports checked/validated by a reviewer from the AppSec team
Accessibility
If this MR adds or modifies a component, take a few moments to review the following:
- All actions and functionality can be done with a keyboard.
- Links, buttons, and controls have a visible focus state.
- All content is presented in text or with a text equivalent. For example, alt text for SVG, or
aria-labelfor icons that have meaning or perform actions. - Changes in a component’s state are announced by a screen reader. For example, changing
aria-expanded="false"toaria-expanded="true"when an accordion is expanded. - Color combinations have sufficient contrast.
Edited by Austin Regnery