fullscreennotification.cpp Example File

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#include "fullscreennotification.h"
#include <QGraphicsOpacityEffect>
#include <QPropertyAnimation>
#include <QSequentialAnimationGroup>
FullScreenNotification::FullScreenNotification(QWidget *parent)
    : QLabel(parent)
    , m_previouslyVisible(false)
{
    setText(tr("You are now in full screen mode. Press ESC to quit!"));
    setStyleSheet(
        "font-size: 24px;"
        "color: white;"
        "background-color: black;"
        "border-color: white;"
        "border-width: 2px;"
        "border-style: solid;"
        "padding: 100px");
    setAttribute(Qt::WA_TransparentForMouseEvents);
    auto effect = new QGraphicsOpacityEffect;
    effect->setOpacity(1);
    setGraphicsEffect(effect);
    auto animations = new QSequentialAnimationGroup(this);
    animations->addPause(3000);
    auto opacityAnimation = new QPropertyAnimation(effect, "opacity", animations);
    opacityAnimation->setDuration(2000);
    opacityAnimation->setStartValue(1.0);
    opacityAnimation->setEndValue(0.0);
    opacityAnimation->setEasingCurve(QEasingCurve::OutQuad);
    animations->addAnimation(opacityAnimation);
    connect(this, &FullScreenNotification::shown,
            [animations](){ animations->start(); });
    connect(animations, &QAbstractAnimation::finished,
            [this](){ this->hide(); });
}
void FullScreenNotification::showEvent(QShowEvent *event)
{
    QLabel::showEvent(event);
    if (!m_previouslyVisible && isVisible())
        emit shown();
    m_previouslyVisible = isVisible();
}