Scroll left toc to active entry

[fekete-robert]

Useful when the left-side toc is longer than the screen.
Fixes #348 and #257

This is an update of the original patch of narrenfrei

Notes:

• It seems that on Firefox there is a side-effect of using https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollIntoView that causes the page to scroll its main content even if it's not needed. I haven't seen this problem in Chrome and Safari
• It might be better to use https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollIntoViewIfNeeded but that's not yet supported in every browser

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[LisaFC]

@narrenfrei do you want to take a look at this?

[fekete-robert]

Hi @LisaFC and @narrenfrei, have you had a chance to review this PR?

[raum51]

I think in the netlify preview the functionality doesn't work, because the sample page ist built with the cached sidebar sidebar_cache_limit: 10.

Also the script that adapts the sidebar menu when the sidebar cache is use have to set the id of the span to td-sidebar-nav-active-item. Actually only a class get added.

docsy/layouts/partials/sidebar.html

Line 11 in 6488360

$("#td-section-nav #{{ $mid }}-li span").addClass("td-sidebar-nav-active-item");

[fekete-robert]

Many thanks for the comments, I'll try to fix them later this week

[fekete-robert]

@raum51 : I've added a line to add the id to the span, but if the cache limit is low, the scrolling doesn't work for some reason. Any ideas?