Simply put, glass is molecularly geometric - building actuated buttons into the glass itself isn't very probable. But a film of actuated buttons could be added much like with capacitive touch sensors today.
Microfluidics is near the 100nm range today. Throw in a bit of ferrofluid and something like this is at least plausible. The challenge is in making all this transparent. The microfluidic channels would need to not create a 'screen door effect' and the fluid transparent.
The Royal Society of Chemistry's 'Lab on Chip' Youtube Channel [1] is a good place to daydream about the future of such things.
@1m18s you see a syringe of fluid - so it's something similar. Maybe two laser-cut capacitive films with non-conductive fluid pumped through to make static 'buttons'. Probably a better MVP than what I suggested earlier :).
Microfluidics is near the 100nm range today. Throw in a bit of ferrofluid and something like this is at least plausible. The challenge is in making all this transparent. The microfluidic channels would need to not create a 'screen door effect' and the fluid transparent.
The Royal Society of Chemistry's 'Lab on Chip' Youtube Channel [1] is a good place to daydream about the future of such things.
[1] http://www.youtube.com/user/labonachipVideos/videos