Refactor & allow to specify offset on onKeyDown

[golota60]

hey! thanks for the awesome library
downstream issue: algolia/docsearch#1572

There's an issue downstream in https://github.com/algolia/docsearch where the search results are obstructed when you move up through the list using arrow keys(see downstream issue for more details). It's most likely happening cause scrollIntoView and scrollIntoViewIfNeeded in onKeyDown are not accounting for the sticky header. My proposed fix for it is to replace those with scrollTo/scrollBy
and allow to specify xOffset/yOffset by consumers. That would allow a fix to be implemented downstream.

If you give me a green light I'd be happy to implement it!

[sarahdayan]

Hey @golota60, I replied on the DocSearch ticket since this might be fixable with CSS.

Also, did you mistakenly mentioned onKeyDown in the issue title? This issue doesn't seems related to it, but correct me if I'm wrong.

I'll update this ticket as we move forward.

[golota60]

Hey,
onKeyDown is not responsible for the issue, but that's where they keyup/keydown logic is located, so the potential fix(feature?/change?) would need to be implemented there i think(might be wrong though). That being said, your suggestion in downsteam issue seems to be fixing everything, so we won't need that 😛