(FrameLayout) findViewById - returns null?
You're inflating the layout from travel_map_activity. Xml which only contains one ID: R.id. TravelMapView .
You cannot select items from other layouts ( with a few small exceptions that are more like abuses of the system ).
Are those two Views you are finding (travelMapView and mapFrame) in the same layout travel_map_activity. Because the layout you provided isn't holding travelMapView at all, yet you don't get a NullPointerException there.
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