How to detect which frontends are connected #11920

Activity

1. tacaswell commented on Oct 20, 2019

   

   tacaswell

   on Oct 20, 2019

   Contributor

   More actions

   It is impossible to tell by design. It is possible for more than one front end to connect which makes any automatic configuration based on that problematic.
2. hmaarrfk commented on Oct 20, 2019

   

   hmaarrfk

   on Oct 20, 2019

   Author

   More actions

   Hmmm. Is it possible to tell which frontend is running the current lines of code?
3. tacaswell commented on Oct 23, 2019

   

   tacaswell

   on Oct 23, 2019

   Contributor

   More actions

   I think the protocol is carefully designed to make sure you can not tell. I have gone down this road with Matplotlib and concluded it was not possible (and mostly agree with the design).
4. hmaarrfk commented on Oct 23, 2019

   

   hmaarrfk

   on Oct 23, 2019

   Author

   More actions

   So how does matplotlib detect which backwnd to use? Could other libraries use the same detection mechanism? Qt vs Web vs tk???
5. ccordoba12 commented on Oct 23, 2019

   

   ccordoba12

   on Oct 23, 2019

   Member

   More actions

   So how does matplotlib detect which backwnd to use?

   I think it doesn't. It's up to the frontend to try to use the Matplotlib backend set by the user.

   For example, if you set %matplotlib notebook then interactive plots will be rendered as expected inside the notebook, but nothing will be shown in Spyder (and no error will be generated) because qtconsole can't handle Javascript content.

   This limitation will be overcome in our side once we add a new pane in Spyder capable of rendering any web content that comes from the kernel. This is our top priority for Spyder 5, to be released next year.
6. tacaswell commented on Oct 24, 2019

   

   tacaswell

   on Oct 24, 2019

   Contributor

   More actions

   The only 'auto' thing we do is try to detect if there is a running GUI event loop and we use that one (which is something that is fully on the kernel side of things, see https://github.com/matplotlib/matplotlib/blob/349e2e9e8a33c5a45d2935aae86561bdea10e55b/lib/matplotlib/cbook/__init__.py#L39-L76 ).