This is a good question, i am currently creating an app for Navigation (ships).
The main activity layout with all the buttons and global information is loaded, and then depending on the type of information the operator wants to display i have different layouts loaded into a panel (that take up about 66% of the screen area).
This way the globall info is always there and the user selected items is displayed within the panel (these panels display, positional info, engine and shaf RPM, Thruster Info and also things like doors that are open or closed for safety).
I wasn't sure if this was best practice but it just seemed logical to me and works well.
Not sure i answered your question, i just think sometimes one way works better than another.
Regards
Stu