feat(Listbox): Allow Listbox to be found in content projection

[alkrobinson]

Feature Description

The Listbox cdk directive could be used as a select component's options. This would be nice because it has built in accessibilty features and keyboard interactions. The problem is if those select component options are content projected they cannot find their parent listbox directive.

Use Case

So if I wanted my custom select component implementation to look like this:

The custom select options are being content projected and the custom select logic would look something like this:

The select option that is not content projected is working as expected but the content projected ones are not finding their parent listbox and therefore not behaving correctly.

Stackblitz for reference : https://stackblitz.com/edit/angular-ivy-tcfqrs?embed=1&file=src/app/select/select.component.ts

[lukonik]

Hey there,
Do you have any plans to develop this feature?
cdkListbox is nice feature, and because of this issue, we can't create generic components like select, and multi-select with content-projection options