相关头文件

#include <QGraphicsBlurEffect>
#include <QGraphicsDropShadowEffect>
#include <QGraphicsColorizeEffect>
#include <QGraphicsOpacityEffect>

代码如下：

EffectDialog::EffectDialog(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::EffectDialog)
{
    ui->setupUi(this);

    QGraphicsDropShadowEffect *shadow = new QGraphicsDropShadowEffect();
    shadow->setXOffset(5);
    shadow->setYOffset(5);
    ui->label->setGraphicsEffect(shadow);

    QGraphicsBlurEffect *blur = new QGraphicsBlurEffect();
    blur->setBlurRadius(3);
    ui->label_2->setGraphicsEffect(blur);

    QGraphicsColorizeEffect *colorize = new QGraphicsColorizeEffect();
    colorize->setColor(QColor(255, 125, 0));
    ui->label_3->setGraphicsEffect(colorize);

    QGraphicsOpacityEffect *opacity = new QGraphicsOpacityEffect();
    opacity->setOpacity(0.7);
    ui->label_4->setGraphicsEffect(opacity);
}

效果如下：

多谢，亲爱的美美。