是不是你的代码有问题哦?

newaction=new QAction(tr("&New"),this);
newaction->setIcon(QIcon(":/Images/new.png"));
newaction->setShortcut(QKeySequence::New);
newaction->setStatusTip(tr("Create new file ."));
...
filemenu=menuBar()->addMenu(tr("&File"));
filemenu->addAction(newaction);
...