1 MainWindow::MainWindow(QWidget *parent) : 2     QMainWindow(parent), 3     ui(new Ui::MainWindow) 4 { 5     ui->setupUi(this); 6     //设置最小大小 7     this->setMinimumSize(200,100); 8  9     QPushButton *push=new QPushButton("quit",this);10     //设置大小和位置11     push->setGeometry(64,40,76,33);12     //设置字体13     push->setFont(QFont("Times",25,QFont::Bold));14     //程序结构15     connect(push,SIGNAL(clicked(bool)),qApp,SLOT(quit()));16 }