窗体部件之QMenu

QMenu常见的分为以下几种：

（1）右键菜单

void Widget::contextMenuEvent(QContextMenuEvent *event){    m_menu = new QMenu(this);    m_act = new QAction("hello", m_menu);    m_menu->addAction(m_act);    //注意exec和popup两种方式的区别//    m_menu->exec(QCursor::pos());//    m_menu->popup(QCursor::pos());    m_menu->popup(mapToGlobal(event->pos()));}

（2）按钮菜单

    pushBtn = new QPushButton("hello", this);    menu = new QMenu(this);    act1 = new QAction("1", menu);    act2 = new QAction("2", menu);    menu->addAction(act1);    menu->addAction(act2);    pushBtn->setMenu(menu);    //去掉按钮显示下标    pushBtn->setStyleSheet("QPushButton::menu-indicator{image:None;}");

（3）托盘菜单

    QSystemTrayIcon *systemTrayIcon = new QSystemTrayIcon(this);    systemTrayIcon ->setToolTip(QString("hello"));    systemTrayIcon ->setIcon(QIcon(":/icon.png"));    QMenu *menu = new QMenu(this);    QAction *act = new QAction("hello", menu);    menu->addAction(act);    systemTrayIcon->setContextMenu(menu);    systemTrayIcon->show();    systemTrayIcon->showMessage(QString("托盘"), QString("hello"));