Refactoring with Move Method Implementations to Source File provides C/C++ users with an efficient way of moving all methods of a class from a header file to a source file, in a single operation.
Move all implementations of a class by invoking the refactoring from the name of a class, not from one of its methods. The refactoring is available in the Quick Action and Refactoring menu (Shift+Alt+Q).
Select the implementations to move in the dialog that opens.
Implementations from nested classes can be moved in the same operation. If you select the nested class in the initial dialog, a second dialog opens to move its methods.
See the documentation for Move Implementation to Source File regarding the location of implementations and special handling of template implementations.