setVisibility
Sets the visibility of all floor layers.
If the map is in the process of being destroyed, the method exits early and returns false. When isVisible is true, only the current floor (identified by mCurFloorId) is made visible. When isVisible is false, all floor layers are hidden if they are currently visible.
Return
true if the operation was attempted; false if the map is being destroyed
Parameters
isVisible
true to show the current floor, false to hide all floors