move 设置一个widget的位置

            MultiChoiceWidget* pWidget = new MultiChoiceWidget(this);

            pWidget->AddPluginList(pluginList);

            QPoint pGlobal = btn->mapToGlobal(btn->rect().center());

            QPoint pHomePage = mapFromGlobal(pGlobal);

            pWidget->move(pHomePage.x() + 25, pHomePage.y() - pWidget->height()/2);