NativeScript: Declarative UI not updating?

stop-nsThis is just a heads up so that others don't waste the time I wasted; trying to figure it out...

So, I've been working all day on a really cool NS app for a client; made LOTS of graphical changes;  Gradients, shadows, borders, opacity, custom built fonts, themes, tap effects, etc -- looks and acts really sweet...

So I start the app up again and it changes several fields frequently so all of a sudden the display appears locked up; none of the values are changing while just watching it...   I click on a button and the display updates; properly.  Weird.  So I do it again, and again it freezes about 10 seconds into doing updates; interacting with certain things in the app and bam the display starts updating again; and 5 seconds later it the ui stops and is no longer updating again...   Argh...  Inconsistent issues are hard to trace..

So I run the copy of the app that I had deployed to my actual phone from this morning; and everything works great -- not as pretty; but no display glitches.

Ok, so now I'm thinking some change I did has broken the Observables some how, maybe the Obs notification is crashing, or being eaten.  So I start debugging and basically waste about a bit of time tracing things back and even add code to verify that the Observable is sending property change notices properly...   So, after doing a bit of work, everything programmatically looks correct; everything is still bound, the binding context is still valid; the Observable is sending the updates properly; everything looks correct in memory; just the labels don't update...

I start writing up an issue in the NS repo to ask for some more pointers on how to trace down why an Observable is sending notifications, the label is bound and listening; and the label actually shows the updates for a random numbers of seconds but then just randomly stops updating (but can be "kicked" by doing things in the app)..  Yes, that weird of a problem.

Well, before I finish writing up the issue I decide to try a hail-mary as my dad would say.  I killed the emulator; started it back up and....   Everything works....    Ugh, wasted a lot of time; but the good new is it wasn't my app -- my app works great...

So the point of this story -- if you start getting any unexpected random display update glitches; try rebooting the emulator...

 

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