Filebrowser paging draft

[cnydw]

Addressing issue https://github.com/jupyter-server/jupyter_server/issues/538

Added a page parameter to the request, to select the pages. The updated API is not mature , would love to hear suggestions.

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[mwakaba2]

Hi @cnydw, any updates on this? It'd be great to make the filebrowser experience more performant.

[cnydw]

@mwakaba2 @vidartf

I made a simple update, however I feel my paging design is far from ideal. The paging design like https://github.com/jupyter-server/jupyter_server/issues/538#issuecomment-856884253 isn't very intuitive. Most file browsers don't have pages, instead they only utilize the scrollbar.

A better design would probably abandon the page selection, and will look just like the original file browser. When opening a folder, It will display a small number of files, and when the scrollbar moves to the end, it activates loading more items (if there is any). However this scrollbar activated design will probably not work with my current simple implementation in the jupyter_server backend.

More discussion with JupyterLab side is probably needed.