一.效果
二.实现
ui->menu->setWindowFlags(ui->menu->windowFlags() | Qt::FramelessWindowHint | Qt::NoDropShadowWindowHint);
ui->menu->setAttribute(Qt::WA_TranslucentBackground, true);
ui->menu->setStyleSheet("QMenu{padding: 5px; background-color: white;"
"border: 1px solid rgb(200, 200, 200);"
"border-radius: 5px}"
"QMenu::item:selected{color:black;"
"background-color: rgb(229, 229, 229);}"
"QMenu::separator{"
"height: 2px;"
"background-color: rgb(229,