WIP: Time viewer tool bar with SVG icons

[GuillaumeFavelier]

This PR, following a discussion with @hoechenberger and strongly inspired by cbrnr/mnelab#61, adds a tool bar with useful bindings to the features of _TimeViewer:

It's also an item of #7162 since it adds buttons to the interface.

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This is not compatible with #7592

[GuillaumeFavelier]

I considered removing the main menu but it's still useful when time_viewer=False for taking screenshot

Latest version:

[GuillaumeFavelier]

I also thought about a button like the following:

that would display additionnal informations. It could be used to clarify the auto-scaling feature or time index @larsoner (relevant for #7247 (comment))

[larsoner]

@GuillaumeFavelier any way we can use unicode for the icons rather than bundling new binary images?

[hoechenberger]

any way we can use unicode for the icons rather than bundling new binary images?

I don't think we'd find anything even closely as good-and-balanced-looking, tbh… also if you use a font, the icons could end up looking different on every system! -1 on unicode icons from my side for now :)

[hoechenberger]

@larsoner What could work, potentially, are FontAwesome fonts, but personally I'm in favor of bundling SVG icons

[GuillaumeFavelier]

any way we can use unicode for the icons rather than bundling new binary images?

It should be possible but it may have a totally different result on old version of PyQt5. It may require some particular processing like we did in #7257 (comment)

[hoechenberger]

@cbrnr Since you've probably been through this decision process personally with MNELAB, what's your stance on this?

[hoechenberger]

@GuillaumeFavelier Just tested on macOS and looks and works beautifully. I really like it! Also the availability of buttons now could compensate for some of the shortcomings of PyVista. For example, I don't think we'd need to hold on to the orientation slider, but we could add toolbar buttons for that instead (like in FreeView).

[GuillaumeFavelier]

rather than bundling new binary images

Sorry, we can exclude the images and mne.qrc from MANIFEST.in since they're already built in resources.py

[cbrnr]

I'd go with SVG icons, I didn't even consider using unicode symbols. Just make sure to set app.setAttribute(Qt.AA_UseHighDpiPixmaps) (https://github.com/cbrnr/mnelab/pull/102/files).

[GuillaumeFavelier]

Just to be clear, to make it work with PyQt, only the built resources.py is necessary. So if the issue is about storing the images, they can be hosted in another repo. and reused only when the interface changes to update resources.py.

[GuillaumeFavelier]

Closing in favour of #7592 to move forward. At least a prototype is available here if needed.

[hoechenberger]

LGTM once CI goes green. Thanks for your work, @GuillaumeFavelier

[codecov]

Codecov Report

Merging #7589 into master will increase coverage by 0.07%.
The diff coverage is 90.74%.

@@            Coverage Diff             @@
##           master    #7589      +/-   ##
==========================================
+ Coverage   90.05%   90.12%   +0.07%     
==========================================
  Files         452      454       +2     
  Lines       83035    83387     +352     
  Branches    13127    13208      +81     
==========================================
+ Hits        74780    75156     +376     
+ Misses       5403     5375      -28     
- Partials     2852     2856       +4     

[larsoner]

Works great, thanks @GuillaumeFavelier