Google on Monday detailed the display notch requirements it's imposing on original equipment manufacturers seeking to utilize Android P, in addition to sharing some advice for developers who want to make the most of screen cutouts and optimize their apps for smartphones that feature them. Android P is the first iteration of the company's mobile operating system that offers native support for display notches, though the functionality also comes with a number of conditions OEMs need to fulfill.
Any commercial implementation of Android P hence must extend the height of the notification bar to at least match the size of the notch on the host device while the thereof is running apps that don't demand different behavior in portrait mode. Due to that state of affairs, most apps optimized for Android Oreo should also work in Android P with no issues even if their developers choose not to tweak them in order to specifically account for screen cutouts. Some issues may still present themselves during fullscreen mode transitions and in cases of apps that are hard-coded to communicate with the status bar height function, whether in order to alter it or simply read it. Google is recommending developers to use the WindowInsetsCompat class in order to obtain status bar height with minimal risk.
As Android P comes with a dedicated display notch API, developers can decide how their apps will utilize the cutout area, with Google urging them to consider laying out content over it so as to deliver a more immersive, full-screen experience to users. Besides the aforementioned status bar height requirement, OEMs implementing Android P must also ensure the cutout area is fully letterboxed while their devices are used in landscape orientation, Google confirmed. The tech giant is also recommending developers to prioritize targeting 18:9 displays that are presently extremely popular and then shift their resources to taller aspect ratios. Most Android devices with display notches use a 19:9 image format, though more unconventional aspect ratios such as 18.5:9 and 18.9:9 have also been commercialized over the last 18 months. Android P is set to hit the stable channel by early September, according to Google's official OS roadmap.