Q_DISABLE_COPY(Systeminfo),'Systeminfo' does not name a type

[shree_121]

i am using systeminfo class from Qt installer framework where i got error as 'Systeminfo' does not name a type. here is my systeminfo.cpp file:

#include "systeminfo.h"
#include <QSysInfo>

namespace QInstaller {

SystemInfo::SystemInfo(QObject *parent) : QObject(parent)
{
}

QString SystemInfo::currentCpuArchitecture() const
{
    return QSysInfo::currentCpuArchitecture();
}

QString SystemInfo::kernelType() const
{
    return QSysInfo::kernelType();
}

QString SystemInfo::kernelVersion() const
{
    return QSysInfo::kernelVersion();
}

QString SystemInfo::productType() const
{
    return QSysInfo::productType();
}

QString SystemInfo::productVersion() const
{
    return QSysInfo::productVersion();
}

QString SystemInfo::prettyProductName() const
{
    return QSysInfo::prettyProductName();
}

} // namespace QInstaller

systeminfo.h

#ifndef SYSTEMINFO_H
#define SYSTEMINFO_H

#include <QObject>

namespace QInstaller {

class SystemInfo : public QObject
{
    Q_OBJECT
    Q_DISABLE_COPY(SystemInfo)

    Q_PROPERTY(QString currentCpuArchitecture READ currentCpuArchitecture CONSTANT)
    Q_PROPERTY(QString kernelType READ kernelType CONSTANT)
    Q_PROPERTY(QString kernelVersion READ kernelVersion CONSTANT)
    Q_PROPERTY(QString productType READ productType CONSTANT)
    Q_PROPERTY(QString productVersion READ productVersion CONSTANT)
    Q_PROPERTY(QString prettyProductName READ prettyProductName CONSTANT)

public:
    explicit SystemInfo(QObject *parent = 0);

    QString currentCpuArchitecture() const;

    QString kernelType() const;
    QString kernelVersion() const;
    QString productType() const;
    QString productVersion() const;
    QString prettyProductName() const;
};

} // namespace QInstaller

#endif // SYSTEMINFO_H

please help to resolve this error.

[Christian Ehrlicher]

Your header compiles fine here. Apart from this - there's no need for this macro there since QObject is not copyable so SystemInfo is also not copyable.

[shree_121]

#there's no need for this macro there since QObject is not copyable so SystemInfo is also not copyable.
hello @Christian-Ehrlicher , do you mean that I should remove Q_DISABLE_COPY(SystemInfo) line and compile again?

[mrjj]

@shree_121
Yes. as QObject handles that for you.
Clean your build folder and try to compile again.

[shree_121]

now i am getting error as 'SystemInfo' has not been declared .

[Christian Ehrlicher]

@shree_121 said in Q_DISABLE_COPY(Systeminfo),'Systeminfo' does not name a type:

now i am getting error as 'SystemInfo' has not been declared .

Then you've another problem somewhere else - please show the complete error message and also make sure that no other header defines 'SYSTEMINFO_H'

[shree_121]

@Christian-Ehrlicher, @mrjj thank you so much now it built successfully, Can you tell me how can i print my OS kernel type in console using QString SystemInfo::kernelType() const.

[mrjj]

@shree_121
use std:.cout ?
if console app ?
or qDebug()

[shree_121]

ohh i used std::cout(console application) but exactly i am not sure where i have to write. Do i have to use signal and slot in main.cpp to execute QString SystemInfo::kernelType() const in systeminfo.cpp. please reply it will really help me.

[mrjj]

Hi
its just a function call so no need for signal or anything complex.
Note that std::xxx is buffered with Qt and you must flush it to print at once.

std::cout << "my type=" << QSysInfo::kernelType().toStdString() << std::flush;

this is for the Qt class. but its the same syntax with your wrapper.

[JonB]

@shree_121
No signals/slots. Did you try something like:

SystemInfo si;
std::cout << si.kernelType().toStdString() << std::flush;

As an architectural comment: all the methods of Qt's QSysInfo are static. Not sure what you are trying to add by creating a wrapper class deriving from QObject, requiring instantiating and with a QObject parent, etc. For example, you could never have written your SystemInfo class and simply called

std::cout << SystemInfo::kernelType().toStdString() << std::flush;

Up to you.

@mrjj

but its the same syntax with your wrapper.

Similar, but the way he's written it a SystemInfo instance will need creating to call his methods.

[mrjj]

@jonb
thx for clearing up the difference between needing an instance and having static functions. :)
Its an important distinction.

[JonB]

@mrjj
The OP's instance approach would be fine if/when he has something to put in the instance to make it have a point. He may well do that, just at the moment there is no indication of what he might store in it, nor what connection it would have to a QObject or parent. Anyway I just mentioned so that he is aware he will need to create an instance, which he might not be.

[mrjj]

@jonb
Indeed.
Also, such wrapper would be useful for exposing it to QML.

[JonB]

@mrjj said in Q_DISABLE_COPY(Systeminfo),'Systeminfo' does not name a type:

Also, such wrapper would be useful for exposing it to QML.

Ah, that I would not have known. As I said, OP may have his reasons.

[shree_121]

@mrjj , @JonB Both ways worked for me. Thank you.