Help with screen redraw / onUpdate()

Former Member over 10 years ago

I've been playing around with a few approaches at building watch faces.

I'm a bit confused by how often the screen is re-drawn, my understanding was that after some activity onUpdate() gets called once per second for six seconds and then once per minute in order to maintain a balance between good watch face aesthetics and battery life.

However, if I start up a new project in eclipse it demonstrates a simple watch face, which calls onUpdate() every second without fail so now I'm a bit confused why this happens. ( Code https://gist.github.com/hyakuhei/c543c41033891f8fccdf )

I'm sure there's some documentation I'm missing somewhere, can someone point me in the right direction please?

-Rob

jim_m_58 over 10 years ago

In the simulator, there is "low power" on the top menu bar, and there you can switch between enter low power, and exit low power. This changes it from every second to every minute, and back.

Former Member over 10 years ago

Thank you, this makes a lot of sense!

Are there some conditions where the watch will only run in low-power? When I try my more elaborate test code, the low power option in the simulator is greyed out... ?

travis.vitek over 10 years ago

The option is greyed out if your primary view does not inherit from Ui.WatchFace. The device runs in low power mode (updates once every 60 seconds) normally. When the user lifts their arm to look at the watch face, it enters normal mode (updates once per second) for 10 seconds, and then returns back to low power mode.

Former Member over 10 years ago

Thank you for your quick reply, I was in fact inheriting from Ui.View (I'm still in the "poke things and see what happens" phase of learning how to write code for these watches).