Qt 实现启动动画

受bilibili客户端启发，同款效果动画

初始化

void MainWindow::initOverlayLabelAnimation()
{

    // 在central widget上创建一个覆盖的label
    overlayLabel = new QLabel(this);
    // 加载logo图片
    QPixmap pix = QPixmap(PNG_LINEX);
    float scaled = 0.3;
    overlayLabel->setPixmap(pix.scaled(pix.width() * scaled, pix.height() * scaled, Qt::KeepAspectRatio, Qt::SmoothTransformation));
    overlayLabel->setAlignment(Qt::AlignCenter);
    overlayLabel->setGeometry(0, 0, geometry().width(), geometry().height());
    if (mInterfaceColor == QColor(Qt::black)) {
        overlayLabel->setStyleSheet(QString("background-color: rgb(12,12,12);"));
    }
    else {
        overlayLabel->setStyleSheet(QString("background-color: rgba(%1, %2, %3, %4);").arg(mInterfaceColor.red()).arg(mInterfaceColor.green()).arg(mInterfaceColor.blue()).arg(mInterfaceColor.alpha()));
    }

    // 设置透明度效果
    QGraphicsOpacityEffect* opacityEffect = new QGraphicsOpacityEffect(overlayLabel);
    overlayLabel->setGraphicsEffect(opacityEffect);
    opacityEffect->setOpacity(1);

    // 创建渐变动画
    mOverlayLabelAnimation = new QPropertyAnimation(opacityEffect, "opacity");
    mOverlayLabelAnimation->setDuration(600); // 持续时间ms
    mOverlayLabelAnimation->setStartValue(1);
    mOverlayLabelAnimation->setEndValue(0);
    mOverlayLabelAnimation->setEasingCurve(QEasingCurve::InOutQuad);

    // 设置动画结束的操作
    connect(mOverlayLabelAnimation, &QPropertyAnimation::finished, overlayLabel, &QLabel::hide);
    connect(mOverlayLabelAnimation, &QPropertyAnimation::finished, mOverlayLabelAnimation, &QPropertyAnimation::deleteLater);
    connect(mOverlayLabelAnimation, &QPropertyAnimation::finished, this, &MainWindow::SignalOverlayLabelAnimationFinished);

}

启动

void MainWindow::showWindow()
{
    this->show();
    
    // 延时1秒后启动动画
    QTimer::singleShot(1000, this, [=]() {
        mOverlayLabelAnimation->start();
        });
}