#include <qapplication.h>#include <qwidget.h>#include <qlistview.h>class MyMainWindow:public QWidget{ public:    MyMainWindow(); private:    QListView *listview;    QListViewItem *topic1;    QListViewItem *topic2;    QListViewItem *topic3;    QListViewItem *item;};MyMainWindow::MyMainWindow(){ setGeometry(100,100,300,300);  listview = new QListView(this); listview->setGeometry(0,0,400,400); listview->setRootIsDecorated(true); listview->addColumn("Book"); listview->addColumn("Solid Copies"); listview->addColumn("Price"); topic1 = new QListViewItem(listview,"Topic 1"); topic2 = new QListViewItem(listview,"Topic 2"); topic3 = new QListViewItem(listview,"Topic 3"); item = new QListViewItem(topic1,"Book 1","21,000","$29.99"); item = new QListViewItem(topic2,"Book 2","19,000","$24.99"); item = new QListViewItem(topic3,"Book 3","14,000","$99.99"); item = new QListViewItem(topic3,"Book 1","3800,000","$29.99"); item = new QListViewItem(topic3,"Book 2","16,000","$24.99"); item = new QListViewItem(topic3,"Book 3","9,000","$99.99"); item = new QListViewItem(topic3,"Book 1","3800,000","$29.99"); item = new QListViewItem(topic3,"Book 2","16,000","$24.99"); item = new QListViewItem(topic3,"Book 3","9,000","$99.99");}main(int argc,char **argv){ QApplication a(argc,argv); MyMainWindow w; a.setMainWidget(&w); w.show(); a.exec();}