dock1=new QDockWidget(tr("treeview"),this);
dock1->setAllowedAreas(Qt::LeftDockWidgetArea);
addDockWidget(Qt::LeftDockWidgetArea, dock1);
display_frameMenu->addAction(dock1->toggleViewAction());//让树形列表显示和不显示,
dock1->setMinimumWidth(250);
dock1->showMinimized();