What's the purpose of tools:openDrawer=“start” when creating a DrawerLayout (with NavigationView) from the wizard?

Question

Creating an activity with navigation drawer in Android Studio causes this to be shown in the XML code:

Answer 1

It makes the navigation drawer visible on the preview screen in Android Studio essentially mimicking the user swiping the drawer onto the screen.

Without this attribute, you would see only the content view of the main screen.

I haven't tried it but I suspect substituting "start" for "end" would make the drawer on the right of the screen open (assuming there is one of course).