enum Window {THEM_DAU_SACH, HIEU_CHINH_DAU_SACH, DANH_MUC_SACH, THEM_DOC_GIA, HIEU_CHINH_DOC_GIA, XOA_DOC_GIA, MUON_SACH, TRA_SACH, TOP_TEN}; enum SubWindow {NHAP_SACH, THEM_SACH, HIEU_CHINH_SACH, XAC_NHAN_TRA_SACH, XAC_NHAN_LAM_MAT_SACH}; enum ScanType{ ONLY_NUMBER, ONLY...