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c++windowswinapiatlwtl

Set dialog box window class name

What's the proper way to subclass a dialog so that its class name will change to a specified one, so it would be later found with FindWindow (from another process)?

class CMyDialog : public CDialogImpl<CMyDialog, CWindow> {
public:
    enum { IDD = IDD_MAIN };

    // error: CDialogImpl doesn't support GetWndClassInfo
    DECLARE_WND_CLASS(L"unique class name") 
};
Solution

  • After some additional search I found How to provide your own Window class name for an MFC dialog box. There is nothing MFC specific though.

    In summary:

    • Add CLASS "your class name" field to the dialog resource. It can be done from within the GUI: disable MFC Mode on the resource file properties, then Class Name property appears in the dialog properties.

    • Subclass the WC_DIALOG class as follows:

      WNDCLASSEXW wc;
wc.cbSize = sizeof(WNDCLASSEX);
::GetClassInfoExW(0, WC_DIALOG, &wc);
wc.lpszClassName = "your window class";
wc.style &= ~CS_GLOBALCLASS;
::RegisterClassExW(&wc);

    Extra reading: https://blogs.msdn.microsoft.com/oldnewthing/20100215-00/?p=14943/