what does this mean " error: ISO C++ forbids declaration of --- with no type?

[qtlinuxnewbie]

HI
i am getting this error "error: ISO C++ forbids declaration of ‘-----’ with no type"
when do we get this error ??

Thnkx in advance...

[squidge]

Post some code.

[Kumosan]

Most likely you forgot a necessary forward declaration or include.

[qtlinuxnewbie]

@fatjuicymole
mainwindow.h file.. i am getting the error in this code.

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
 
#include <QThread>
#include <QMessageBox>
 
#include <QtGui/QMainWindow>
 
#include "sampleThread.h"
 
 
namespace Ui
{
    class MainWindow;
}
 
class MainWindow : public QMainWindow
{
    Q_OBJECT
 
public:
    MainWindow(QWidget *parent = 0);
    ~MainWindow();
 
 
private:
    Ui::MainWindow *ui;
 
   sampleThread *newThread;//in this line
};
 
#endif // MAINWINDOW_H

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QThread>
#include <QMessageBox>

#include <QtGui/QMainWindow>

#include "sampleThread.h"


namespace Ui
{
    class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = 0);
    ~MainWindow();


private:
    Ui::MainWindow *ui;

   sampleThread *newThread;//in this line
};

#endif // MAINWINDOW_H

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[wysota]

What is the contents of sampleThread.h?

[qtlinuxnewbie]

#ifndef SAMPLETHREAD_H
#define SAMPLETHREAD_H
#include <QMessageBox>
#include <QThread>
 
#include "mainwindow.h"
 
class sampleThread:public QThread
{
 
    public:
 
    sampleThread();
    void run();
    QWidget *targetWidget;
 
};
 
 
#endif // SAMPLETHREAD_H

#ifndef SAMPLETHREAD_H
#define SAMPLETHREAD_H
#include <QMessageBox>
#include <QThread>

#include "mainwindow.h"

class sampleThread:public QThread
{

    public:

    sampleThread();
    void run();
    QWidget *targetWidget;

};


#endif // SAMPLETHREAD_H

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[Kumosan]

Your thread class in sampleThread.h... Is it really named 'Thread' or 'SampleThread' or 'sampleThread'.... The compiler does not know your 'Tread'.

Interrupted by a colleague. :-)

Try: samleThread *newThread;

[qtlinuxnewbie]

actually it is sampleThread only

[Kumosan]

actually it is sampleThread only

??? Pardon? I don't understand.

It is either:
QThread *newThread;
or:
sampleThread *newThread;

You don't have a class 'Thread'.

[qtlinuxnewbie]

may be i was not clear for u .
it is

sampleThread *newThread

sampleThread *newThread

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[squidge]

In the code you have posted, you use just "Thread", not "sampleThread".

[qtlinuxnewbie]

i changed the posted code to sampleThread and tried to build but i am getting the same error.

[wysota]

You have a loop in your includes - mainwindow.h includes sampleThread.h which again includes mainwindow.h. Use a forward declaration in mainwindow.h instead of including sampleThread.h or don't include mainwindow.h in the other file.