移动到Qt5时的编译错误：“类型”尚未声明

问题描述

使用Qt 5.2.1编译旧的Qt项目（可能由Qt 4.8创建）：
Lan messenger开源：

Use Qt 5.2.1 to compile old Qt Project (maybe created by Qt 4.8):Lan messenger open source:

#ifndef QTSINGLEAPPLICATION_H
#define QTSINGLEAPPLICATION_H

#include <QApplication>

class QtLocalPeer;

#if defined(Q_WS_WIN) || defined(Q_OS_WIN32)
#  if !defined(QT_QTSINGLEAPPLICATION_EXPORT) && !defined(QT_QTSINGLEAPPLICATION_IMPORT)
#    define QT_QTSINGLEAPPLICATION_EXPORT
#  elif defined(QT_QTSINGLEAPPLICATION_IMPORT)
#    if defined(QT_QTSINGLEAPPLICATION_EXPORT)
#      undef QT_QTSINGLEAPPLICATION_EXPORT
#    endif
#    define QT_QTSINGLEAPPLICATION_EXPORT __declspec(dllimport)
#  elif defined(QT_QTSINGLEAPPLICATION_EXPORT)
#    undef QT_QTSINGLEAPPLICATION_EXPORT
#    define QT_QTSINGLEAPPLICATION_EXPORT __declspec(dllexport)
#  endif
#else
#  define QT_QTSINGLEAPPLICATION_EXPORT
#endif

class QT_QTSINGLEAPPLICATION_EXPORT QtSingleApplication : public QApplication
{ Q_OBJECT

public:
QtSingleApplication(int &argc, char **argv, bool GUIenabled = true);
QtSingleApplication(const QString &id, int &argc, char **argv);
QtSingleApplication(int &argc, char **argv, Type type);
#if defined(Q_WS_X11)
QtSingleApplication(Display* dpy, Qt::HANDLE visual = 0, Qt::HANDLE colormap = 0);
QtSingleApplication(Display *dpy, int &argc, char **argv, Qt::HANDLE visual = 0, Qt::HANDLE cmap= 0);
QtSingleApplication(Display* dpy, const QString &appId, int argc, char **argv,     Qt::HANDLE visual = 0, Qt::HANDLE colormap = 0);
#endif

bool isRunning();
QString id() const;

void setActivationWindow(QWidget* aw, bool activateOnMessage = true);
QWidget* activationWindow() const;

// Obsolete:
void initialize(bool dummy = true)
    { isRunning(); Q_UNUSED(dummy) }

public Q_SLOTS:
bool sendMessage(const QString &message, int timeout = 5000);
void activateWindow();


Q_SIGNALS:
void messageReceived(const QString &message);


private:
void sysInit(const QString &appId = QString());
QtLocalPeer *peer;
QWidget *actWin;
};

#endif // QTSINGLEAPPLICATION_H

错误：'类型'已声明

我不知道如何修复这些错误。
任何人会帮助吗？
谢谢。

I dont know how to fix these error.Will anyone help?Thank you.

推荐答案

从Qt仓库中的commit中引用：

Quote from commit in Qt repository :

。

作为一个解决方法，如果你没有在你的QtSingleApplication构造函数中指定类型，那么你可以注释掉它，仍然继续使用QtSingleApplication没有它。

As a workaround if you don't specify the type in your QtSingleApplication constructor then you can comment it out and still keep using QtSingleApplication without it.

qtsingleapplication.h：
line 70：

qtsingleapplication.h:line 70:

//QtSingleApplication(int &argc, char **argv, Type type);

qtsingleapplication.cpp：
第176行：

qtsingleapplication.cpp:line 176:

/*QtSingleApplication::QtSingleApplication(int &argc, char **argv, Type type) :
QApplication(argc, argv, type)
{
    sysInit();
}*/

这篇关于移动到Qt5时的编译错误：“类型”尚未声明的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！