"Class not found" in Android XML but can be imported

I have an android project set up with various views. I made this project A a dependency for a second project, B. When I attempt to declare a view in my layout XML file in project B with a view from project A I get the two errors in the screenshot below. ("Class not found" & "unbound prefix"). When I import the same class into the main_activity.java file however, there is no error.