title: Is every activity/fragment's xml implicitly wrapped around with a FrameLayout?
body: <p>Let's say in an activity's xml it's using a LinearLayout as its root layout. And the activity during runtime wants to show a dialog/dialog fragment. Wouldn't the activity's xml have to be implicitly wrapped around with a FrameLayout for this to work due to needing to control the Z axis of views? Like you open the activity's xml and you see LinearLayout. However, behind the scenes, it's wrapped in a FrameLayout. Is this correct?</p>