QT使用右键菜单QMenu

看下面动画

关键代码:

#pragma once
 
#include <QtWidgets/QMainWindow>
#include<QAction>
#include<QMenu>
#include <qmessagebox.h>
#include <qobject.h>
 
#include "ui_MyQmenu.h"
 
class MyQmenu : public QMainWindow
{
  Q_OBJECT
 
public:
  MyQmenu(QWidget *parent = Q_NULLPTR);
 
  private slots:
    void clicked_A();
    void clicked_B();
    void clicked_C();
 
private:
  Ui::MyQmenuClass ui;
  QAction *A ;
  QAction *B;
  QAction *C;
};

#include "MyQmenu.h"
 
MyQmenu::MyQmenu(QWidget *parent)
  : QMainWindow(parent)
{
  ui.setupUi(this);
 
  A = new QAction(QString::fromLocal8Bit("打开(o)"));
  B = new QAction(QString::fromLocal8Bit("新建(n)"));
  C = new QAction(QString::fromLocal8Bit("关闭(q)"));
 
  A->setObjectName("A");
  B->setObjectName("B");
  C->setObjectName("C");
 
  addAction(A);
  addAction(B);
  addAction(C);
 
  setContextMenuPolicy(Qt::ActionsContextMenu);
 
  connect(A, SIGNAL(triggered()), this, SLOT(clicked_A()));
  connect(B, SIGNAL(triggered()), this, SLOT(clicked_B()));
  connect(C, SIGNAL(triggered()), this, SLOT(clicked_C()));
 
}
void MyQmenu::clicked_A()
{
  QMessageBox::about(NULL, "tips", "A"+A->objectName());
}
 
void MyQmenu::clicked_B()
{
  QMessageBox::about(NULL,"tips","B" + B->objectName());
}
 
void MyQmenu::clicked_C()
{
  QMessageBox::about(NULL, "tips", "C" + C->objectName());
}