call the other dialog through dialog

[narumi]

hi..

Im new to Qt and this is my first time programming c++ along with Qt. Im now working on my undergraduate project to create a front-end to mencoder utility. I develop this application using KDevelop and this is what I want to do right now:
- call the other dialog from one running dialog

my project consists of several form, I got one main form that will call other form with a click of button. let say in my main form I want to call 'settings' form. So my main window source file i did this:

#include "mainwindow.h"
#include "configuration.h"
 
mainWindow::mainWindow(QWidget* parent, Qt::WFlags fl)
: QWidget( parent, fl ), Ui::mainWindow()
{
	setupUi(this);
}
 
mainWindow::~mainWindow()
{
	connect(btnSettings, SIGNAL(clicked()),this,SLOT(settings()));
}
 
void mainWindow::settings()
{
	configuration * conf = new configuration();
	conf->show();
}

#include "mainwindow.h"
#include "configuration.h"

mainWindow::mainWindow(QWidget* parent, Qt::WFlags fl)
: QWidget( parent, fl ), Ui::mainWindow()
{
	setupUi(this);
}

mainWindow::~mainWindow()
{
	connect(btnSettings, SIGNAL(clicked()),this,SLOT(settings()));
}

void mainWindow::settings()
{
	configuration * conf = new configuration();
	conf->show();
}

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but it did not work after I've compile it and click on the button. Where did I made a mistake?