A question about AE plugin development Panelator template

Hello, I have a question to consult, that is, I use AEGP Panelator this sample template to write a plug-in, I wrote a custom function called GetSelectedLayerNames(). This function is used to get the name of the selected layer. Because this function is used to AEGP_GetNewCollectionFromCompSelection the function, the function inside the first parameter is the ID of the plug-in. So I put the implementation of GetSelectedLayerNames() in Panelator.cpp. Then I created a custom button in PanelatorUI_Plat.cpp that, when pressed, executes GetSelectedLayerNames() in Panelator.cpp. I don't know if my above idea is correct, so I want to instantiate the Panelator object in PanelatorUI_Plat.cpp, but I find that in this example the Panelator class is declared and implemented in panelator.cpp. I can't instantiate him. So should I move the declaration of the Panelator class into panelator.h? Or is there an easier way? Hope to get your answer, thank you!