Material-components-web: Implement Expand/Colapse for mdc-list

[KaRkY]

It would be nice to have Expand/Collapse on mdc-list as documented here.

https://material.io/guidelines/components/lists-controls.html#lists-controls-types-of-list-controls

[Garbee]

Related to #46

Same JS logic for both, just slightly different style on top to fit into lists.

[yeelan0319]

Duplicate of #46 , we will close this one.

[vanor89]

This doesn't really count as the "same" anymore since expansion panels are not part of the MDC Spec, but Expandable/Collapsible lists are.

https://material.io/design/components/lists.html#types

@kfranqueiro sorry for reviving but should this remain closed?

[kfranqueiro]

This is somewhat of a timely question, since I believe we'll be discussing scope/prioritization of List features across platforms sometime soon. We'll likely end up entering new issues to reflect the outcome of that discussion after it happens.

[tamalsaha]

@kfranqueiro , is there any update on the fate of Expandable/Collapsible lists / Expansion panel ?

[Garbee]

From the referenced issue this is a dupe of...

This is no longer within scope of the MD spec, so we're no longer planning to add this to the core MDC Web repository.

[tamalsaha]

But the material.io website still shows a Expand and collapse option for List. Is that going to be support in the MDc components?

[calebccff]

Is there any news on this? I'd really like this feature for a website.

[suhailkc]

Any plan to implement Expand/Collapse?
It's necessary !!

[KingFalse]

Need it!

[clevercodenl]

Also need it

[jfbrennan]

I'm comparing Material Web's markup to M- and want to make sure I'm putting out an accurate comparison. Right now I have to put "Unsupported" for Material, but https://material.io/components/lists#types has this example:

Is there at least a code sample somewhere for achieving that?

[c-dinkel]

This is not a duplicate of #46 any longer, since the spec does not contain the Expansion Panel any more.

This is now an issue again, since expanding and collapsing lists are still part of the spec.