QT——label显示图片

void DanJi_GridFenHhua::_label_show_picture()//网格化分，让label显示一张图片
{
    //设置具体阴影
    QGraphicsDropShadowEffect* shadow_effect = new QGraphicsDropShadowEffect(this);
    shadow_effect->setOffset(0, 0);

    //阴影颜色
    shadow_effect->setColor(QColor(38, 78, 119, 127));
    //阴影半径
    shadow_effect->setBlurRadius(50);
    ui.label_danji->setGraphicsEffect(shadow_effect);
    QPixmap* pixmap = new QPixmap(IMAGE_PATH("dan_ji.png"));  //加载图片

    pixmap->scaled(ui.label_danji->size(), Qt::KeepAspectRatio, Qt::SmoothTransformation);
    ui.label_danji->setScaledContents(true); //是否可以跟随窗口变化的关键一句
    ui.label_danji->setPixmap(*pixmap); //label 显示图片
}