3_5.cpp

一个qt设计的教程

#include <qapplication.h>
#include <qwidget.h>
#include <qpushbutton.h>
#include <qfont.h>
#include <qlabel.h>

class MyMainWindow:public QWidget
{
 public:
    MyMainWindow();
 private:
    QPushButton *b1;
    QLabel *label;
};

MyMainWindow::MyMainWindow()
{
 setGeometry(100,100,200,170);
 
 b1 = new QPushButton("Quit",this);
 b1->setGeometry(20,20,160,80);
 b1->setFont(QFont("Times",18,QFont::Bold));

 label = new QLabel(this);
 label->setGeometry(10,110,180,50);
 label->setText("If you click the button above,
                 the whole program will exit");
 label->setAlignment(AlignCenter);

 connect(b1,SIGNAL(clicked()),qApp,SLOT(quit()));
}

main(int argc,char **argv)
{
 QApplication a(argc,argv);
 MyMainWindow w;

 a.setMainWidget(&w);
 w.show();
 a.exec();
}