class FMyDialog : public FModalDialog {
        Fxxxxx c_xxxxx;
        ...... .......;
public:
        FMyDialog()
          : FModalDialog()
          {}

        int DoModal(FWnd *pOwner);
        Bool Create(FWnd *pOwner);
protected:
        Bool CreateControls();
};

int FMyDialog::DoModal(FWnd *pOwner) {
        return FModalDialog::DoModal(pOwner,zzzzz);
}

Bool FMyDialog::Create(FWnd *pOwner) {
        return FModalDialog::Create(pOwner,zzzz);
}

Bool FMyDialog::CreateControls() {
        if(!FModalDialog::CreateControls())
                return False;
        if(!c_xxxxx.Create(this,yyyyy))
                return False;
        ...
        return True;
}