Behave consistent around dark theme

Kind (Required)

• Proposal / Discussion

Overview (Required)

• Currently app is themed with system settings (related: #465) on launch. It seems to behave like MODE_NIGHT_FOLLOW_SYSTEM so switching system dark settings updates switch in app as well.
• However, once check/uncheck the dark theme switch, it behaves as MODE_NIGHT_YES/MODE_NIGHT_NO. At that time, switching system dark settings no longer updates switch in app.
• It is good to add MODE_NIGHT_FOLLOW_SYSTEM so that user can choose fixed(dark/light) or system dependent.

How about it?

Links

• https://medium.com/androiddevelopers/appcompat-v23-2-daynight-d10f90c83e94

[ytRino]

yes, I intended what you said maybe. I’m planing that of Gmail app. Both dark/light is app overridables and default is system dependent. If we implement #465 without this, we can no longer have system dependent once user switched it in app. What user will see in preferences screen in app (after #465 )

	without this	with this
launch (not selected any)	“dark” or “light” (behavior is system default)	“system default”
launch with “system default”	(not available)	“system default”
launch with “dark”	“dark”	“dark”
launch with “light”	“light”	“light”

[ytRino]

Thanks! I’ll continue working on this.