Cannot call member function without object

Hi Qt pips,

I'm working with subdirectory project which has 3 subprojects.
Now, I'm having a problem calling the instance of a project to another project.

Here's the code of the header file of project1:

#if !defined(__TRIAL_H__)
#define __TRIAL_H__

#include <qwidget.h>
#include "TrialGlobal.h"

namespace Ui {
class Trial;
}

class TRIALSHARED_EXPORT Trial : public QWidget
{
Q_OBJECT

public:
explicit Trial (QWidget *Parent = 0);
~Trial (void);
Trial *get_instance();

private:

Ui::Trial *Ui;
};

#endif // __TRIAL_H__

source file:

#include <qapplication.h>
#include <qplastiquestyle.h>

#include "Trial.h"
#include "ui_Trial.h"

Trial::Trial (QWidget *Parent) :
QWidget(Parent),
Ui(new Ui::Trial)
{
Ui->setupUi(this);
return;
}

Trial::~Trial (void)
{
delete Ui;
return;
}

Trial *Trial::get_instance()
{
static CAbout TrialInstance;
return &TrialInstance;
}


When trying to instantiate that to project2 using this code:

Trial *newab = Trial::get_instance();
newab->show();

This generates this error:

cannot call member function 'Trial *Trial::get_instance()' without object

Second thing was can I instantiate this without using any static function or static declarations?


Thanks in advance guys.