qt 菜单栏创建

.h文件内容：

#pragma once

#include <QtWidgets/QMainWindow>
#include "ui_QtWidgetsApplication2.h"
#include <QLabel>
class QtWidgetsApplication2 : public QMainWindow
{
Q_OBJECT

public:
QtWidgetsApplication2(QWidget *parent = nullptr);
~QtWidgetsApplication2();

QStatusBar *statusbar;
QLabel* label;

public slots:
void OnActionTest();

private:
Ui::QtWidgetsApplication2Class ui;
};

cpp内容：新建文件连接了打开图片得函数用于测试

#include "QtWidgetsApplication2.h"
#include <QMenuBar>
#include <QToolBar>
#include <QStatusBar>
#include <QLabel>
#include <QDockWidget>
#include <QTextEdit>
#include <QFileDialog>
#include <QDebug>
#pragma execution_character_set("utf-8")

QtWidgetsApplication2::QtWidgetsApplication2(QWidget *parent)
: QMainWindow(parent)
{
ui.setupUi(this);

resize(800, 600);//设定窗口大小

QMenuBar *menubar = new QMenuBar(this);
setMenuBar(menubar);

   QMenu * filename = new QMenu("文件", this);
   QMenu *editmenu = new QMenu("编辑", this);
   QMenu *buildname = new QMenu("构建", this);

   //QMenu *filename = menubar->addMenu("文件");
   //QMenu *editmenu = menubar->addMenu("编辑");
   //QMenu *buildname = menubar->addMenu("构建");

   QAction *pActionTest = new QAction("打开图片", this);
   QAction *pActionTest1 = new QAction("打开文件", this);
   QAction *pActionTest2 = new QAction("关闭文件", this);
   filename->addAction(pActionTest);
   filename->addAction(pActionTest1);
   filename->addSeparator();
   filename->addAction(pActionTest2);

   QAction *pActionTest3 = new QAction("恢复", this);
   editmenu->addAction(pActionTest3);
   QAction *pActionTest4 = new QAction("构建所有项目", this);
   buildname->addAction(pActionTest4);

   menubar->addMenu(filename);
   menubar->addMenu(editmenu);
   menubar->addMenu(buildname);

   // ToolBar
   QToolBar *toolbar = new QToolBar(this);
   addToolBar(Qt::TopToolBarArea, toolbar);
   toolbar->addAction("新建");
   toolbar->addSeparator();
   toolbar->addAction("打开");
   toolbar->addSeparator();
   toolbar->addAction("关闭");

   // statusbar
   statusbar = new QStatusBar(this);
   setStatusBar(statusbar);

   QLabel *label1 = new QLabel(this);
   label1->setText("状态栏");
   statusbar->addWidget(label1);

   // DockWidgets 浮动窗口停靠窗口中心部件的停靠位置
   // 验证：浮动窗口是否在中心部件的左侧
   //注意：这里还有问题，小窗口会可能导致菜单栏点击出现BUG
   QDockWidget *dockWidget = new QDockWidget("小窗口", this);
   addDockWidget(Qt::LeftDockWidgetArea, dockWidget);

   // Center Widget 文本编辑器或浏览器部分
   QTextEdit *edit = new QTextEdit(this);
   setCentralWidget(edit);

   label = new QLabel(this);
   label->move(200, 200);                               //将标签移动到(0,100)位置
   label->resize(200, 160); //设定标签大小
   //label->setStyleSheet("border:1px solid black"); //设定边框

connect(pActionTest, &QAction::triggered, this, &QtWidgetsApplication2::OnActionTest);

}
void QtWidgetsApplication2::OnActionTest() {
   QString filename = QFileDialog::getOpenFileName(this, tr("Open Image"), QDir::homePath(), tr("(*.jpg)\n(*.bmp)\n(*.png)")); //打开图片文件，选择图片
   if (filename.isEmpty()) {
       return;
   }
   QImage image = QImage(filename); //图片初始化
   if (!image.isNull())
   {
       label->setPixmap(QPixmap::fromImage(image));
       label->setScaledContents(true);//图片自适应大小
       //label->show();
       statusbar->showMessage(tr("Open Image Success!"), 3000); //打开成功时显示的内容

   }
   else
   {
       statusbar->showMessage(tr("Open Image Failed!"), 3000);
       return;
   }
}
QtWidgetsApplication2::~QtWidgetsApplication2()
{}

效果图展示：

此界面可能会出现一个bug，因为添加了小窗口和文本编辑器，会导致菜单栏点击时有点儿小问题，不用小窗口可以去掉。

qt 菜单栏创建

悦读