【发布时间】：2015-04-16 12:22:36
【问题描述】：
这是Qt项目中的.pro文件：
QT += core gui
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = abc123
TEMPLATE = app
LIBS += -L/usr/local/lib
INCLUDEPATH += /usr/local/include
SOURCES += main.cpp\
mainwindow.cpp
HEADERS += mainwindow.h
FORMS += mainwindow.ui
当我尝试编译这段代码时，Qt 给出了 19 个不同的错误（无论我在类本身中写了什么）：
/Users/user0/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:44: error: variable has incomplete type 'class Q_WIDGETS_EXPORT'
class Q_WIDGETS_EXPORT QSizePolicy
^
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:44: error: expected ';' after top level declarator
class Q_WIDGETS_EXPORT QSizePolicy
^
;
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
Q_DECLARE_OPERATORS_FOR_FLAGS(QSizePolicy::ControlTypes)
^
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:158: error: expected a class or namespace
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:162: error: variable has incomplete type 'Q_WIDGETS_EXPORT'
Q_WIDGETS_EXPORT QDataStream &operator<<(QDataStream &, const QSizePolicy &);
^
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:162: error: expected ';' after top level declarator
Q_WIDGETS_EXPORT QDataStream &operator<<(QDataStream &, const QSizePolicy &);
^
;
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:163: error: redefinition of 'QDataStream'
Q_WIDGETS_EXPORT QDataStream &operator>>(QDataStream &, QSizePolicy &);
^
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:163: error: expected ';' after top level declarator
Q_WIDGETS_EXPORT QDataStream &operator>>(QDataStream &, QSizePolicy &);
^
;
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:167: error: variable has incomplete type 'Q_WIDGETS_EXPORT'
Q_WIDGETS_EXPORT QDebug operator<<(QDebug dbg, const QSizePolicy &);
^
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:167: error: expected ';' after top level declarator
Q_WIDGETS_EXPORT QDebug operator<<(QDebug dbg, const QSizePolicy &);
^
;
/Users/user05/Qt5.4.0/5.4/clang_64/lib/QtWidgets.framework/Headers/qsizepolicy.h:170: error: expected a class or namespace
inline void QSizePolicy::transpose() {
^
/usr/local/include/QtGui/qcursor.h:171: error: must use 'class' tag to refer to type 'QDataStream' in this scope
Q_GUI_EXPORT QDataStream &operator<<(QDataStream &outS, const QCursor &cursor);
^
class
/usr/local/include/QtGui/qcursor.h:171: error: must use 'class' tag to refer to type 'QDataStream' in this scope
Q_GUI_EXPORT QDataStream &operator<<(QDataStream &outS, const QCursor &cursor);
^
class
我使用的是 Qt 5.4.0 版本，我的操作系统是 OS X 10.9.4。您知道可能出了什么问题吗？
【问题讨论】：
-
创建一个非 Qt 项目，如普通 C++ 应用程序。
-
@Md.MinhazulHaque 但我想使用 Qt 项目的功能，即我想在其中使用 GUI 表单创建器。
-
与您当前的错误无关，但在 2015 年使用 opencv 的 c-api 是 no-no
标签： c++ qt opencv makefile qt-creator