MRG: Link _TimeViewer time slider with vertical time line

[GuillaumeFavelier]

This PR adds a vertical line to indicate the current time on the matplotlib canvas.

I also did quite the refactor there as _TimeViewer.__init__ was getting too long.

It's an item of #7162

[codecov]

Codecov Report

Merging #7423 into master will increase coverage by 4.45%.
The diff coverage is 75.23%.

@@            Coverage Diff             @@
##           master    #7423      +/-   ##
==========================================
+ Coverage   85.61%   90.07%   +4.45%     
==========================================
  Files         454      454              
  Lines       82227    82358     +131     
  Branches    13003    13025      +22     
==========================================
+ Hits        70397    74182    +3785     
+ Misses       9162     5351    -3811     
- Partials     2668     2825     +157     

[larsoner]

Pushed a commit to enable bidirectional control (clicking in the MPL axis will change the brain and sliders). @GuillaumeFavelier I don't know if it was the cleanest way so feel free to take a look and fix if need be.

Now this works the way I would expect so LGTM +1 for merge from me

[GuillaumeFavelier]

feel free to take a look and fix if need be.

Could not have done better.

I just added to_time_index() to _Brain

[larsoner]

@GuillaumeFavelier can we make that private and also get rid of index_for_time? Things like index_for_time seem like cruft left over from PySurfer that we don't want in the public interface of our new Brain class.

[GuillaumeFavelier]

@larsoner there are multiple places where I consider that time_idx is int (which was guaranteed by index_for_time with the default parameters). This might take more time than expected to refactor.

[larsoner]

Okay, might not be worth it then...

[GuillaumeFavelier]

I took care of it in the latest commit 363e81f, what do you think?

[larsoner]

Thanks @GuillaumeFavelier