Backlight detection?

Spinal 28 days ago

I have just started coding my first watchface and would like to add a colour feature that would depend on knowing if the backlight is activated or not.

I couldn't find anything at first glance, but I might have missed it.

Is it possible to detect if the backlight is on or off in a watchface?

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Johnny.ConnectIQ 27 days ago in reply to FlowState +1

That's correct for MIP screen, we don't have a way to tell if the backlight is on, however for AMOLED products, since system 7, we introduced a new API "System.getDisplayMode" that can be used to…

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0 Johnny.ConnectIQ 28 days ago

"backlight" is a term that's kinda out dated, as more Garmin devices are now using AMOLED screens, which doesn't have a "backlight".

if you are coding for watchface, there are "WatchFace.onEnterSleep" and "WatchFace.onExitSleep" that you can use to detect screen power mode.

You can consider the screen has backlight is on, a.k.a "High Power Mode", after "WatchFace.onExitSleep" .

0 Spinal 28 days ago in reply to Johnny.ConnectIQ

Cool, it seems to be the info I need, but the screens only seems to update a second or two after the light is changed...

[update] Not what I need, even on an MIP screen, it checks when you're 'looking at the watch', whic seems like a stupid feature for an always on screen. So the effect was being applied even when the light was off.

0 FlowState 27 days ago in reply to Spinal

Spinal said:
even on an MIP screen, it checks when you're 'looking at the watch', whic seems like a stupid feature for an always on screen

I get where you're coming from, but for MIP devices, low power mode is in effect when you're "not looking at the watch" to save energy. CIQ watchfaces can still update the screen once per second, but there's a power budget which has to be followed.

On AMOLED devices, the motivation is to save energy *and* prevent burn-in, and there's different restrictions on how the screen can be updated.

Couple of references:

[https://forums.garmin.com/developer/connect-iq/f/discussion/5156/1hz-watch-faces---q-a]

[https://forums.garmin.com/developer/connect-iq/f/discussion/192673/how-to-enable-an-always-on-mode-for-venu-amoled]

[https://forums.garmin.com/developer/connect-iq/f/discussion/367507/10-lit-pixels-or-10-brightness]

0 FlowState 27 days ago in reply to Spinal

Spinal said:
So the effect was being applied even when the light was off.

Yeah I don't think there's any way for CIQ to detect backlight (MIP) or full brightness (AMOLED) per se. For example, the user could change their settings so that backlight / full brightness is not applied on the wrist turn gesture, but a watchface would still go into high power mode when the user turns their wrist.

0 Johnny.ConnectIQ 27 days ago in reply to FlowState

That's correct for MIP screen, we don't have a way to tell if the backlight is on, however for AMOLED products, since system 7, we introduced a new API "System.getDisplayMode" that can be used to return LOW, HIGH or OFF for AMOLED screen. I'd recommend using that to replace "onEnter/ExitSleep".

You can either call "System.getDisplayMode" in onUpdate call, then act accordingly, or switch power mode logic by listening to the new "Application.onDisplayModeChanged" function, similar to what you would typically do in "onEnter/ExitSleep"

see:

https://developer.garmin.com/connect-iq/api-docs/Toybox/System.html#getDisplayMode-instance_function

https://developer.garmin.com/connect-iq/api-docs/Toybox/Application/AppBase.html#onDisplayModeChanged-instance_function

Note: there are some documentation errors regarding the display mode, those will get fixed soon.