Android 9.0 P will be released to the public in August 2018, but beta testers can already install it on Google's own Pixel devices and a few other smartphones. In the latest release, there's a pretty hidden setting that lets you turn on a system-wide, dark design that changes the look of your Quick Settings panel and other menus.
It's similar to the automatic system theme introduced in Android 8.1 Oreo except you do not have to use black or dark wallpaper to trigger it. Instead, you can manually pick a bright theme, a dark theme, or the existing automatic theme.
To try it out, make sure you're running the latest beta version of Android P, then go to your phone's main menu and tap "View." From there, press "Advanced" to expand further options. At the bottom is the topic "Device" ̵
The Settings menu does not change the colors or your apps. But there are still many places where the dark theme applies. For more information, see