Code review request

[GoogleCodeExporter]

Branch name: music-redesign

Link to the relevant commit(s): 
https://code.google.com/p/oppia/source/detail?r=c94c4e8a4bb8187469f609fad16a5d7e
5ae409a6&name=music-redesign#

Purpose of code changes on this branch: Implement the 'low-hanging' design 
suggestions for the music interaction

When reviewing my code changes, please focus on: code health and UI

(Note: I think I'll do this fix in stages -- the second part, having a shadow 
for the cursor, will be more complicated than I thought. For instance, we'll 
probably have to snap the ghost image to the grid as well.)

After the review, I'll merge this branch into: develop

Original issue reported on code.google.com by s...@seanlip.org on 14 Feb 2015 at 10:53

[GoogleCodeExporter]

LGTM!

As far as the ghost note image goes, does it have to snap to the grid? If we 
just have some javascript that changes the cursor to a transparent whole note 
(eventually - quarter, eight, etc.) and then when a user clicks on a staff line 
it could "drop" the note the same way we do now I think. I'm interested in 
hearing more about your implementation too.

Original comment by wagnerdm...@gmail.com on 15 Feb 2015 at 5:01

• Changed state: Done

[GoogleCodeExporter]

Thanks!

I haven't fully figured out my implementation yet. I was just thinking it would 
be a bit weird if you dropped the note in one location and it immediately 
teleported to another location -- if you look at the current implementation of 
the interaction, the note always falls in the position it's currently visible 
in, and I think that's a good UX pattern to follow.

Original comment by s...@seanlip.org on 15 Feb 2015 at 5:14

[GoogleCodeExporter]

That's a good point, I wouldn't want that either. I'll think about this some 
more.

Original comment by wagnerdm...@gmail.com on 15 Feb 2015 at 5:31