consul/ui/packages/consul-ui/app/modifiers/aria-menu.mdx

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# aria-menu
Modifier based `{{aria-menu}}` helper based on GitHub top menu keyboard interactions.
Functionality is based on a11y focussed keyboard navigation of aria menus and currently only supports vertical-like navigation (but feel free to add horizontal, it should be straight forwards.
Features:
- `Enter`/`Space` to open the menu and immediately focus the first item
- Click to open the menu but _not_ focus the first item
- `Escape` to close the menu and focus the original trigger (`aria-labelledby`)
- When open, arrow keys will cycle through the menu items, and therefore not leave the menu.
- When open, tabbing through the menu items will _not_ cycle but instead return to the natural DOM tabbing flow once the start/end is reached.
ARIA attributes are not automatically added for you and you should make use of `role="menu"`, `role="menuitem"`, `role="none"` and `role="separator"` (if required). You should also take care to use the `aria-labelledby` attribute along with a correct `id` attribute on the trigger for the menu.
You should also take care to use `aria-haspopup="menu"` and `aria-controls="id"` if required. BUt only if you require the additional disclosure type functionality. These additional aria attributes are not functionally relevant to `{{aria-menu}}` itself.
Clicking outside will _not_ close the menu by default, if you require this functionality please combine with our `{{on-outside 'click'}}` modifier (see example).
In the example below, the Before Trigger and After Trigger don't do anything, they are only there to demonstrate tabbing functionality with natural DOM tabbing order.
```hbs preview-template
<div
style={{style-map
(array 'display' 'flex')
}}
>
<button
type="button"
>
Before trigger
</button>
<div
style={{style-map
(array 'position' 'relative')
}}
>
<button
{{on 'click'
(queue
(set this 'event')
(set this 'open' (not this.open))
)
}}
id="trigger"
type="button"
aria-haspopup="menu"
aria-controls="menu-id"
>
Trigger
</button>
{{#if this.open}}
<ul
id="menu-id"
style={{style-map
(array 'position' 'absolute')
(array 'padding' '1rem')
(array 'border' '1px solid var(--token-color-foreground-faint)')
(array 'top' '2rem')
(array 'background-color' 'var(--token-color-surface-primary)')
}}
role="menu"
aria-labelledby="trigger"
{{on-outside 'click' (set this 'open' false)}}
{{aria-menu
openEvent=this.event
onclose=(set this 'open' false)
}}
>
<li role="none">
<button type="button" role="menuitem">Item 1</button>
</li>
<li role="none">
<button type="button" role="menuitem">Item 2</button>
</li>
<li role="none">
<button type="button" role="menuitem">Item 3</button>
</li>
</ul>
{{/if}}
</div>
<button
type="button"
>
After trigger
</button>
</div>
```
## Named Arguments
| Argument | Type | Default | Description |
| --- | --- | --- | --- |
| `openEvent` | `Event` | | The Event used to open the menu, if `pointerType` is empty the first menu element is focussed when open |
| `onclose` | `function` | | A callback called when the menu is closed |