How do I change the orientation of a LinearLayout when a device changes orientation? What changes would be needed in the *.xml's associated *.kt file?
For example, the device is in Portrait and displays a LinearLayout with a vertical orientation. When the device turns and becomes Landscape, the LinearLayout should have a horizontal orientation.
I imagine that two different layouts would be called depending on the configuration change but I'm not sure.
You need to use separate folders for your layouts : layout for portrait mode and layout-land for landscape mode, and put two separate xml files with the same name in each one.
One of xml files with LinearLayout with a vertical orientation and another xml file with LinearLayout with horizontal orientation.
For instance look at How to Add/Create Landscape Layout in Android Studio