PlatformColor's theme update without useColorScheme on Android

[svbutko]

Hi there!

I have an interest and idea to improve PlatformColor support on Android in order to align it with the way it's implemented on iOS

Problem

Currently, to work with theme updates and updating colors is made possible by Appearance module via useColorScheme and utilizing context based on example.

This is a common approach but it has following issues:

• Context has to be created
• Multiple styles and merging of them needs to be done
• Component updates

PlatformColor

There's PlatformColor which helps to get rid of style updates, creation of additional code, and the color can simply be used inside of StyleSheet and no listeners and context hast to be created to simply updated the color on the fly... BUT only on iOS, since on Android we either need to update the whole activity (which is sub-optiomal).

Possible solution

While searching for a solution and going through the code, I noticed that when providing backgroundColor to View (I'm taking View as an example, it's the same logic with other components), in BaseViewManager here, the actual value is being converted from Object to Integer and underlying ReactViewGroup and others receive a simple Integer.

Would it be more rational to provide Object down to ReactViewGroup and other components, and do a conversion there while keeping the original Object and adding onConfigurationChanged (inside the same ReactViewGroup), and when new configuration comes then simply re-apply the color?

While it sounds as something simple, I'm wondering whether it would be correct to do it the way I described? Since the core logic and tests rely on to Integer everywhere. Or is there other place where it could be applied which I missed?

I will be more than happy to create a PR with changes to properties and tests if this is the way, since I believe it will simplify the workload which can be done with theme switching. Thank you!