When is a watchface app stopped and started?

I have trouble understanding when a watch face app is stopped and started.

Obviously when a watch face is first installed and selected it is started. But does it continuously run until you select a different watchface or turn off the watch? For example if you start an exercise activity, you can swipe right on the screen and go back to the watchface. In such a situation was the watchface stopped when the exercise app was started and then restarted when you did the right swipe? Or was the watchface app still loaded in the background, and onUpdate() called when the right swipe happened.

There are other situations as well, like switching to a widget and then back, or when the watch is plugged in to be charged. I'd like to have a better understanding of this as some behaviour in my app is not as expected and I suspect that the app is getting stopped and restarted. I haven't persisted any of the data thinking that the app was "permanently" loaded.

0 jim_m_58 over 5 years ago

When you go to an activity, the watch face stops, In your case when you right swipe, it's started, but stopped if you move to a widget, or you return to the activity,

When you swipe up/down from a watch face and move to the widgets/glances the watch face is also stopped,

If the watch faces has a background service, that can run when other things are being used, but in general, won't run if you are using a CIQ device app.

0 trudelta over 5 years ago in reply to jim_m_58

I use a background service so I tried to mark the variables that I want to persist with (:background) but this didn't work. The variable values were not persisted. I had to resort to using storage. Thx.