Improve button layout

[ian-r-rose]

Some stylistic updates to the dashboard launcher buttons:

1. Remove default buttons, instead show a "Dashboard not connected" message if there is no valid dashboard (fixes Remove default dashboard plots #198).
2. Alphabetize the buttons so they are in a more predictable location (fixes Sort order of plots #199 )
3. Changes the layout so buttons are one-per-line (I had changed it in prehistory to layout row-wise with overflow so we could fit more buttons in, but I think that made things too busy, and also made it tougher to find buttons)

Screenshots:

[jacobtomlinson]

This looks awesome! Nice work @ian-r-rose.

I wonder if we should provide some kind of tip to the user when the dashboard isn't connected on how to connect one.

[ian-r-rose]

Good idea. There’s plenty of room for a more detailed message

…

On Tue, Jul 20, 2021 at 1:02 PM Jacob Tomlinson ***@***.***> wrote: ***@***.**** commented on this pull request. This looks awesome! Nice work @ian-r-rose <https://github.com/ian-r-rose>. I wonder if we should provide some kind of tip to the user when the dashboard isn't connected on how to connect one. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#200 (review)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABLWQN5AQ6QISUQUAHIZ3JDTYVJTPANCNFSM5AVRAUPA> .

[ian-r-rose]

Now with a more informative message:

[jacobtomlinson]

Awesome!

[ian-r-rose]

Thanks for the review @jacobtomlinson!

[jrbourbeau]

This looks great!

[GenevieveBuckley]

Thanks for doing this @ian-r-rose

I've been using jupyter lab instead of just the notebook more and more these days, and was just coming over here to whinge about exactly this! It's going to be a lot less frustrating now

[ian-r-rose]

Published in dask-labextension==5.1.0

[mrocklin]

Oh man, I am definitely installing that right now

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On Fri, Jul 30, 2021 at 4:06 AM Ian Rose ***@***.***> wrote: Published in dask-labextension==5.1.0 — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#200 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACKZTFT7O62BADCPW23VNDT2JTQJANCNFSM5AVRAUPA> .