很简单，两行代码：
setWindowFlags(Qt::Window|Qt::FramelessWindowHint|
Qt::WindowStaysOnTopHint|Qt::Tool|Qt::X11BypassWindowManagerHint);
this->setWindowOpacity(0.7); //设置窗口透明度
很简单，两行代码：
setWindowFlags(Qt::Window|Qt::FramelessWindowHint|
Qt::WindowStaysOnTopHint|Qt::Tool|Qt::X11BypassWindowManagerHint);
this->setWindowOpacity(0.7); //设置窗口透明度
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