volume control

hi
i only posted the reqired code. this is my full code:
form1.cpp
Code:
#include "form1.h"
#include "ui_form1.h"
 
#include "form2.h"  
 
#include <QPixmap>
#include <QPalette>
#include <QDesktopWidget>
#include <QRect>
#include <QSize>
#include <QApplication>
 
//#include <QIcon>
 
#include <QMouseEvent>  
 
 
#include <phonon/MediaObject>
#include <phonon/AudioOutput>
#include <phonon/VolumeSlider>
#include <QLibrary>
#include <windows.h>
 
Form1::Form1(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Form1)
{
    ui->setupUi(this);
 
    connect(ui->pushButton_24,SIGNAL(clicked()),this,SLOT(showMinimized()));  
 
    // These three line is used for remove 'window title bar'
   this->setWindowFlags(Qt::MSWindowsFixedSizeDialogHint);  
   this->setWindowFlags(Qt::CustomizeWindowHint);          
   this->setWindowFlags(Qt::FramelessWindowHint);         
 
 
   //this->setWindowFlags(Qt::SplashScreen);  
 
   //background image using 'pixmap' and 'palette'
   this->setFixedSize(270,350);
 
   QPixmap pixmap1("E:/workplace/image/two.JPG");
   QPalette p = palette();
 
   //resize image if it is larger than screen size.
   QDesktopWidget* desktopWidget = QApplication::desktop();
   QRect rect = desktopWidget->availableGeometry();
 
   QSize size(rect.width() , rect.height());
   //resize as per your requirement..
   //QPixmap pixmap(pixmap1.scaled(size));
   QPixmap pixmap(pixmap1.scaled(270,350));
 
   p.setBrush(QPalette::Background,  pixmap);
   setPalette(p);
 
   //ui->pushButton->setIcon(QIcon("E:/workplace/image/01.gif"));
 
 
  //connect(ui->horizontalSlider,SIGNAL(volumeChanged(Phonon::MediaObject,Phonon::AudioOutput)),
           //this,SLOT(setVolumeDecibel(Phonon::MediaObject,Phonon::AudioOutput)));
 
 
   QLibrary myLib("C:/Windows/System32/MMSYSTEM.DLL");
 
   myLib.load();
 
   if (myLib.isLoaded())
   {
   connect(ui->horizontalSlider,SIGNAL(sliderMoved(int)),this,SLOT(setAudioOutput()));
   }
 
   //Phonon::MediaObject *mediaObject = new Phonon::MediaObject(this);
   //Phonon::AudioOutput *audioOutput = new Phonon::AudioOutput(Phonon::MusicCategory);
   //Phonon::createPath(mediaObject, audioOutput);
   //mediaObject->setCurrentSource(Phonon::MediaSource("C:/Windows/Suiystem32/MMSYSTEM.DLL"));
   //Phonon::VolumeSlider *volumeSlider = new Phonon::VolumeSlider;
   //volumeSlider->setAudioOutput(audioOutput);
 
}
 
Form1::~Form1()
{
    delete ui;
}
 
void Form1::one()    
{
    text1+="1";
    //text1+=ui->pushButton->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::two()    
{
    text1+="2";
    //text1+=ui->pushButton_4->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::three()   
{
    text1+="3";
    //text1+=ui->pushButton_3->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::four()   
{
    text1+="4";
    //text1+=ui->pushButton_2->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::five()   
{
    text1+="5";
    //text1+=ui->pushButton_5->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::six()    
{
    text1+="6";
    //text1+=ui->pushButton_6->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::seven()    
{
    text1+="7";
    //text1+=ui->pushButton_7->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::eight()     
{
    text1+="8";
    //text1+=ui->pushButton_8->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::nine()    
{
    text1+="9";
    //text1+=ui->pushButton_9->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::star()    
{
    text1+="*";
    //text1+=ui->pushButton_10->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::zero()   
    text1+="0";
    //text1+=ui->pushButton_11->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::hash()    
{
    text1+="#";
    //text1+=ui->pushButton_12->text();
    ui->lineEdit->setText(text1);
}
 
void Form1::clear()    
{
    text1 = "";
    ui->lineEdit->clear();
}
 
void Form1::showForm2() 
{
    Form2 *frm2  = new Form2;
    frm2->show();
    //this->close();
    //this->destroy();
 
}
 
 
void Form1::closeSecondWindow()   
{
    this->close();
}
 
void Form1::mouseMoveEvent(QMouseEvent *event)    
{
    if (event->buttons() & Qt::LeftButton)
    {
        move(event->globalPos() - m_dragPosition);
        event->accept();
    }
}
void Form1::mousePressEvent(QMouseEvent *event)   
{
    if (event->button() == Qt::LeftButton)
    {
        m_dragPosition = event->globalPos() - frameGeometry().topLeft();
        event->accept();
    }
}
i have another form named form2.this is not matter. i need to access the windows volume control with sliders(horizontal slider)