The Multi-threaded Cabinet

Last week, I had some trouble with my desk cabinet at work. I seemed to have inadvertently locked my top drawer. After fiddling around with the cabinet a bit, the drawer had magically opened. This behavior left me puzzled and it wasn't until today that I figured it out. The cabinet is multi-threaded!

The cabinet is small, black with two drawers. Open either drawer alone and everything's fine. Now, try to open both of them at the same time. Race condition!

It turns out if you have one drawer open, you can't open the other drawer! It's locked, literally :P

I can't fathom what merited this particular design choice. Did the designer think something catastrophic would happen if I had both my drawers open at the same time? Nonetheless, it certainly isn't an intuitive feature, nor easily discoverable. But my mind is just a bit more at ease now that I've solved this particular conundrum. :)

--Arkajit

Pandora Pause Indicator

A few months ago for a 6.813 assignment, I'd suggested Pandora as an example of a good user interface. But I'd noted that one thing that annoyed me was that it was hard to tell whether the player was playing or paused. There was a single play/pause button with one function highlighted in orange. Take a look at this snapshot from the old version of the UI and try to guess if the player is playing or paused:


Does the highlighted function showed the current state or the action that would happen if you pressed the button? (Highlight to reveal answer: current state) I'd always mix this up.

Now, it's true that most of the time, the auditory feedback of hearing the song play would tell you which state the player is in. But when your internet connection is flaky and you're trying to figure out whether Pandora doesn't have a connection or is just paused, the lack of state visibility was very annoying.

I later noticed that there was a hidden indicator in the form of a dynamic url change. When you click pause, the url is appended with a #/paused.

This of course isn't too visible, so I'm glad that Pandora just updated their interface to have a very visible pause indicator: a big black paused icon shows up on top of the song's icon. An incredible improvement in visibility -- well done, Pandora! :)


As an added bonus, the big paused indicator does double-duty as a button. It can be clicked to resume playback.

It is worth noting however that Pandora continues to show the current state (paused) rather than the action that will happen if you press the button (play). Contrast this to Hulu whose video player also displays a big black button when paused, except it displays the action (play).

--Arkajit

Cool Music Sites

I love listening to new music, so I drew up a list of some cool music sites. I stumbled upon the first two a couple days ago. I've used the others for a couple of years now and am including them for completeness.

• Just Hear It: type in any artist, song and get a quick list of youtube clips and music videos. The membership component is in private beta, but the search is still very handy.
  
• Musicovery: pick a mood, a decade or two, and some genres and it will start playing that type of music. It also shows a nice visual graph of the songs its playing and similar songs it will be play next.
• Pandora: create a personalized station by entering a favorite artist or song and it'll play similar songs on that station. Say thumbs up/down to make the station home in on the songs you really like.
  
• Last.fm: a music social networking site, has good suggestions for music and presents several useful charts and other visualizations of your listening habbits. You can "scrobble" songs (i.e. have last.fm track them) you listen on your desktop or stream through their online radio.
• Pandora-FM: this bridges Pandora and Last.fm together allowing you to scrobble your Pandora listens to your Last.fm profile. This was pretty useful since I'm often listening to music on Pandora and would like to track my listening habits (e.g. my most popular artist/track in the last week) with Last.fm.

I hope to get around to writing up a longer post comparing some of these services. And I'll update this entry with more links as I find them. Happy Listening :)

--Arkajit