qt2.3.7退出程序

#include <qapplication.h> #include <qpushbutton.h> #include <qfont.h> class MyWidget : public QWidget { public: MyWidget( QWidget *parent=0, const char *name=0 ); }; MyWidget::MyWidget( QWidget *parent, const char *name ) : QWidget( parent, name ) { setMinimumSize( 400, 400 ); setMaximumSize( 400, 400 ); QPushButton *quit = new QPushButton( "Quit", this, "quit" ); quit->setGeometry( 62, 40, 300, 300 ); quit->setFont( QFont( "Times", 18, QFont::Bold ) ); connect( quit, SIGNAL(clicked()), qApp, SLOT(quit()) ); } int main( int argc, char **argv ) { QApplication a( argc, argv ); MyWidget w; w.setGeometry( 100, 100, 400, 400 ); a.setMainWidget( &w ); w.show(); return a.exec(); }