WatchOS beta5: CMSensorRecorder working again (almost)

The Journey of Instability is alive and well.

I have been working the last 4 days to get around this error when attempting to dequeue CMSensorRecorder messages (filed as bug 22300167):

Aug 16 18:23:43 Gregs-AppleWatch sensor WatchKit Extension[174] <Error>: CoreLocation: Error occurred while trying to retrieve accelerometer records!

During a couple dozen debug attempts I was able to see data flowing only once.

Again, it is fun to be on the pre-release train with Apple. Yes, they work hard to improve features at the expense of stability. The balance between getting things working and presenting a stable interface is a tough one to manage. I know this looks better inside the company, where folks can know in advance to not use experimental interfaces. From the outside, the every-two-week, do it a different approach way is tiring. This will slow the adoption of novel features I'm sure.

Here's what the workflow was like to get to this point:

• beta5 upgrade of XCode, iOS9, WatchOS2 (~ 5 hours)
• discover that the metadata in the existing sensor project is somehow incompatible
• manually copy over the code to a newly generated project, now simulator and hardware are working (~ 8 hours)
• port the sensor recorder using the new protocol (a mere 20 minutes)
• after numerous sessions to real hardware (simulator doesn't support accelerometer) realize that I don't know how to work around the above bug (~ 8 hours)

As many of you have lived; the repeated reboots, hard starts, 'disconnect and reconnect', yet another restart because the iPhone screen is wedged, restart debug session because it times out, etc. isn't the most productive development environment. But I persist.

Code is updated here. Works most of the time now. Working on additional tests around restart, etc.