1. Create a MFC multi-document project, and the content of the following figure will be automatically generated;
2. Add CMainView: public CFormView (it will bring a Dialog resource, which is a user-defined window) and CMainDoc: public CDocument MFC class ；
3. In the InitInstance() function of DaraProcess.cpp, comment out the window that comes with the system and add custom window information.
4. Realize the function
