QMainWindow(一)

mainwindow.h:

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

class MainWindow : public QMainWindow
{
    Q_OBJECT
public slots:
    void foo();
public:
    MainWindow(QWidget *parent = 0);
    ~MainWindow();
private:
    void QMenBar_init();

    };

#endif // MAINWINDOW_H

mainwindow.cpp:

#include "mainwindow.h"
#include<QMenuBar>
#include<QMenu>
#include<QDebug>
MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
 QMenBar_init();
}
void MainWindow::QMenBar_init()
{
this->resize(600,480);
QMenuBar * qm =this->menuBar();
QMenu * wen_jian  = new QMenu("文件(&F)",qm); //快捷方式"Alt+F"
QMenu*bian_ji   = new QMenu("编辑(&E)",qm);
QMenu * gou_jian= new QMenu("构建(&B)",qm);
QMenu* tiao_shi = new QMenu("调试(&D)",qm);
wen_jian->addAction("新建文件或项目(N...)",this,SLOT(foo()),QKeySequence("Ctrl+N"));
wen_jian->addSeparator(); //添加分割线
QMenu* zui_file=wen_jian->addMenu("最近访问的文件(F)");
zui_file->addAction(" ");
zui_file->addSeparator();
zui_file->addAction("清除菜单");

bian_ji->addAction(QIcon("C:/Users/admin/Desktop/QT_Project/untitled/1.png"),"Undo");
tiao_shi->addAction("default")->setCheckable(true);

qm->addMenu(wen_jian);
qm->addMenu(bian_ji);
qm->addMenu(gou_jian);
qm->addMenu(tiao_shi);
}
void MainWindow::foo()
{
    qDebug()<<"打开成功"<<endl;
}
MainWindow::~MainWindow()
{

}

main.cpp:

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

效果: