【QT】QT透明及阴影

窗口透明属性,取值0~1,0表示完全透明，1表示完全不透明
setWindowOpacity(0.5);

 setWindowFlags(Qt::FramelessWindowHint);//设置无边框
 setAttribute(Qt::WA_TranslucentBackground);//设置背景透明

QGraphicsOpacityEffect *opacityEffect = new QGraphicsOpacityEffect ;
opacityEffect->setOpacity(0.1);
ui->label->setGraphicsEffect(opacityEffect);

    //阴影效果
    QGraphicsDropShadowEffect *shadowEffect = new QGraphicsDropShadowEffect;
     //阴影色，透明度
    shadowEffect->setColor(QColor(100,100,100));
    shadowEffect->setBlurRadius(20);//阴影模糊半径
    shadowEffect->setOffset(20);//阴影的偏移值
    ui->label->setGraphicsEffect(shadowEffect);