screenshotOff method
Return true if screenshot capabilities has been
successfully disabled or is currently disabled and false otherwise.
throw UnmimplementedError if not implement
Always returns false when an iOS build runs on a Mac
("Designed for iPhone/iPad" on Apple silicon) — screenshot
prevention is not supported there, though overlays and
screenshot/recording detection still work.
On iOS, also returns false if no window is available yet (e.g.
called before the first frame is rendered). The request is
remembered and protection engages on the next app activation.
Implementation
@override
Future<bool> screenshotOff() async {
_enableProtection();
return true;
}