I'm still a bit new to these concepts but am thinking maybe I can figure out a way to refactor this to be done with composition instead of inheritance. Not totally sure what that would look like though, since I need access to the fragment lifecycle callbacks

Check this out: https://github.com/MarcinMoskala/KotlinAcademyApp/blob/master/android/mobile/src/main/java/org/kotlinacademy/mobile/view/BaseActivity.kt

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