Ambient pressure and pressure history don't match

The blog post is now part of the FAQ.

https://developer.garmin.com/connect-iq/connect-iq-faq/how-do-i-create-a-connect-iq-background-service/

There's also a thread about backgrounding:

forums.garmin.com/.../very-simple-sample-of-a-watch-face-with-a-background-process

Awesome, thanks Jim!

Hey Jim, got the blog post code working and put it on my own watch as I want to use AP which isn't supported in the simulator and no matter how long I leave it in the background, when I go back to the WF, it only returns 1 result. I read in the documentation it will collect and store if multiple temporals run in the background but when ever I print out the "bgData" or data, it is just 1 value. Any ideas how I can collect multiple and read them out?

Also I assume the background process works by storing only when in background and you need to add those values to an array in the WF and once you read the background data, it empties and when in WF mode, you collect as normal, only when you go out of it you top up the main array with the background data when you return to it? That right?

Thanks again for your help :)

In the background, you use 

So you mean in this method (from your example I downloaded):

function onTemporalEvent() {

    var pres = Activity.getActivityInfo().ambientPressure;

        Background.exit(pres);

    }

I should be using Background.getBackgroundData();, append the pres reading and then return the whole thing? So something like:

function onTemporalEvent() {

    var pres = Activity.getActivityInfo().ambientPressure;

var bgstuff = Background.getBackgroundData()

        Background.exit(bgstuff + "," +pres);

    }

That what you mean? In the WF example I downloaded you don't use Background.getBackgroundData() so not sure if that is used before sending the data or if I should use it in the main App or WF to get everything?

Thanks again

Yes.  And in onPackgroundData you need to handle the complex data it may see,

in onTemporalEvent, you may also want to limit the size of what you return - strip off old data if it gets too large.

Thanks Jim, makes sense. And finally, what puts the data into the backgrounddata method? I don't see that part... cannot figure it out from the docs  I understand the .exit method but feels like I should be pushing the data into the background method for it to queue when it .exits? Maybe this is beyond my coding skills but feels like I am very close... 

Thanks again!

The background can run without the main app running.  If that happens, what's returned by Background.exit() is in getBackgroundData().  Let's say that you are recording a run activity.  Your WF doesn't run during that time, but the bacckground will.  So it may queue up a number of samples during that time.

After hours of playing with this and trying things, I finally have it working! Thanks Jim

BTW is there a split type method for a comma delimited string or do I need to write my own method for this? Cannot find any string splitters or array conversion methods. Just Find which would require iterating through the string I guess... 

Thanks again! Huge help :) 

Instead of a comma separated sting, try an array, where you use add() to append something new, and slice() if you need to reduce the size.  That way you can just walk the array .