

# .pro文件
QT += widgetsrequires(qtConfig(filedialog))HEADERS = mainwindow.hSOURCES = main.cpp \mainwindow.cppRESOURCES = sdi.qrc# installtarget.path = $$[QT_INSTALL_EXAMPLES]/widgets/mainwindows/sdiINSTALLS += targetDISTFILES += \document1.txt
## requires(qtConfig(filedialog))
在Qt中,requires(qtConfig(filedialog)) 是一种条件编译的语法。它用于在编译和构建过程中检查是否启用了文件对话框功