#include <qapplication.h>#include <qwidget.h>#include <qslider.h>#include <qprogressbar.h>class MyMainWindow:public QWidget{ public:    MyMainWindow(); private:    QProgressBar *bar;    QSlider *slider;};MyMainWindow::MyMainWindow(){ setGeometry(100,100,200,90);  bar = new QProgressBar(100,this); bar->setGeometry(10,10,180,30); slider = new QSlider(0,100,10,0,Horizontal,this); slider->setGeometry(10,50,180,30);  connect(slider,SIGNAL(valueChanged(int)),bar,SLOT(setProgress(int)));}main(int argc,char **argv){ QApplication a(argc,argv); MyMainWindow w; a.setMainWidget(&w); w.show(); a.exec();}