Sticky header/footer for non-body scroll elements.

[Danielku15]

This PR implements the feature requested in #80. When the corresponding new "relative mode" is enabled via setting the header is positioned within the next parent scrollable element.

[DataTables]

Awesome - thanks for this! Any chance of adding an example for it? Also to confirm, this is one level of relative scrolling? It wouldn't work nested inside two or more scrolling containers. I think that's a fairly unlikely use case, in fairness, but I just want to confirm that wasn't a goal here.

One other thing, are you happy for this to be included under the MIT license?

[Danielku15]

I would have to check how it behaves if you have nested scroll elements. It listens globally for all scroll events on all elements (capture event). The position calculation works then relatively to the parent. It could work since I also check if the scroll parent is visible and positioning is happening absolute. But there might be cases where this does not work out. I'll try to prepare a small sample in JSFiddle.

[Danielku15]

Sample 1: Simple usage (Header Only)
https://jsfiddle.net/ndd45j47/1/

Sample 2: Footer and Header
https://jsfiddle.net/f2wtd6tn/1/

I also tried the nested behavior but it might not be fully as expected for some use cases. The header sticks to the top of the inner scroll window, it does not take any outer scroll into account. It's not directly wrong and would definitly need a setting to switch between the behaviors: https://jsfiddle.net/f2wtd6tn/2/

I also needed to make some fixes, I was accidentally using a jQuery UI specific function that was available in our application. I pulled a copy of the function with slight adjustments.

PS: Yes, I feel fine with including this under MIT in this library.

[jdano1092]

When do you think this will become available? If not already. The examples look great.

[CarlChilton]

Hi all, was this published? I'm experiencing the same issues and the examples look perfect for my purposes. Best wishes.

[DataTables]

Not yet. Still on my (extensive) backlog I'm afraid.

[viicslen]

Hello, any news on this commit?

[CarlChilton]

I found a workaround, which is to disable data tables fixed header and use CSS to set the elements to position sticky with a top of 0. Works perfectly.

[alveri]

Hi. Any news on it?

[DataTables]

No sorry. This issue will be updated when I've been able to make time to dig into this.