I have an application, that has only a service (no UI at all). Other applications can use this service, but service requires permission to run.
Is it possible to request permission from one application for another (so application, that uses service, can request permission). Or the only way to support newest Android versions is to create a notification and activity with permission request like there
One application cannot grant another permission. Permissions are given by application package.
One idea might be to create an Activity A (transparent as R. Zagórski mentioned) that calls your Service within. This activity could check and store your permissions.
Every other application that could want to use your service would just have to send a Broadcast defined by your application and it the service would work fine.
If you are working on a seriously low-level design, there are permission that could be granted by default on system level. Since it is not a common case, please tell me if this is the knowledge you're needing.
Best Regards