Russian Qt Forum

#ifndef GLASS_H
#define GLASS_H

#include <QObject>
#include <QEvent>
#include <QLabel>
#include <QProgressBar>
#include <QDebug>
#include <QColor>
#include <QPropertyAnimation>

class Glass : public QObject
{
    Q_OBJECT
public:
    Glass(QString message = "", int stepCount = 0);
    ~Glass();
    void setMessage(QString message);
    void setStepCount(int stepCount);
    void setAnimationDuration(int duration);
    void init(QWidget *parent);
    void hideAndDelete();
    void infinitely(QString text);

protected:
    QLabel *glass;
    QLabel *infoText;
    QProgressBar *progressBar;
    bool eventFilter(QObject *object, QEvent *event);

private:
    bool
        _haveMessage,
        _haveProgress;
    int
        _stepCount,
        _animationDuration;
    void createControls();
    void positioning();
    QWidget *_parent;

signals:
    void initailized(int);

private slots:
    void afterInit();

public slots:
    void nextStep(QString text);

};

#endif // GLASS_H

#include "glass.h"
#include <QApplication>

Glass::Glass(QString message, int stepCount)
{
    _haveMessage = ((!message.isEmpty()) ? true : false);
    _haveProgress = ((stepCount > 0) ? true : false);
    createControls();
    if(_haveMessage) setMessage(message);
    if(_haveProgress) setStepCount(stepCount);
}

void Glass::createControls()
{
    glass = new QLabel();
    glass->hide();
    if(_haveMessage)
    {
        infoText = new QLabel(0);
        infoText->hide();
        infoText->setAlignment(Qt::AlignCenter);
        infoText->setWordWrap(true);
        infoText->setStyleSheet("color:#fff;");
    }
    if(_haveProgress)
    {
        progressBar = new QProgressBar(0);
        progressBar->hide();
        progressBar->setObjectName(QString::fromUtf8("progressBar"));
        progressBar->setValue(0);
        progressBar->setMaximum(0);
        progressBar->setAlignment(Qt::AlignCenter);
        progressBar->setTextVisible(true);
        progressBar->setOrientation(Qt::Horizontal);
        progressBar->setInvertedAppearance(false);
        progressBar->setTextDirection(QProgressBar::TopToBottom);
        progressBar->setFormat("%p% (%v/%m)");
    }
    _animationDuration = 300;
}

void Glass::setMessage(QString message)
{
    if(_haveMessage) infoText->setText(message);
}

void Glass::setStepCount(int stepCount)
{
    if(_haveProgress) progressBar->setMaximum(stepCount);
}

void Glass::setAnimationDuration(int duration)
{
    _animationDuration = duration;
}

Glass::~Glass()
{
    glass->setMaximumSize(0, 0);
    glass->hide();
    glass->deleteLater();
}

void Glass::hideAndDelete()
{
    if(_haveMessage) infoText->hide();
    if(_haveProgress) progressBar->hide();
    if(_haveMessage) infoText->deleteLater();
    if(_haveProgress) progressBar->deleteLater();
    QPropertyAnimation *animation = new QPropertyAnimation(glass, "geometry");
    animation->setDuration(_animationDuration);
    animation->setEasingCurve(QEasingCurve::InCubic);
    animation->setStartValue(glass->geometry());
    animation->setEndValue(QRect((glass->geometry().x()+glass->geometry().width())/2, (glass->geometry().y()+glass->geometry().height())/2, 0, 0));
    animation->start();
    connect(animation, SIGNAL(finished()), this, SLOT(deleteLater()));
}

bool Glass::eventFilter(QObject *object, QEvent* event)
{
    if(object != this && object != _parent) return false;
    if(event->type() == QEvent::Resize)
    {
        glass->resize(glass->parentWidget()->size());
        glass->move(0, 0);
        positioning();
        return true;
    }
    glass->setFocus();
    return false;
}

void Glass::init(QWidget *parent)
{
    _parent = parent;
    qApp->installEventFilter(this);
    glass->setStyleSheet("background-color: rgba(90, 90, 90, 127);");
    glass->setParent(parent);
    glass->show();
    qApp->installEventFilter(this);
    QPropertyAnimation *animation = new QPropertyAnimation(glass, "geometry");
    animation->setDuration(_animationDuration);
    animation->setEasingCurve(QEasingCurve::InCubic);
    animation->setStartValue(QRect(parent->geometry().width()/2, parent->geometry().height()/2, 0, 0));
    animation->setEndValue(QRect(0, 0, parent->geometry().width(), parent->geometry().height()));
    animation->start();
    connect(animation, SIGNAL(finished()), this, SLOT(afterInit()));
}

void Glass::afterInit()
{
    _stepCount = 0;
    if(_haveMessage)
    {
        infoText->setParent(_parent);
        infoText->show();
    }
    if(_haveProgress)
    {
        _stepCount = progressBar->maximum();
        progressBar->setParent(_parent);
        progressBar->show();
    }
    positioning();
    emit initailized(_stepCount);
}

void Glass::positioning()
{
    int
        pww = glass->parentWidget()->geometry().width(),
        pwh = glass->parentWidget()->geometry().height();
    if(_haveProgress) { progressBar->setGeometry(pww/4, pwh/2-10, pww/2, 21); qDebug() << progressBar->parentWidget() << progressBar->geometry(); }
    if(_haveMessage) infoText->setGeometry(20, pwh/2-31, pww-40, 21);
    qDebug() << "positioning" << _haveProgress << _haveMessage;
}

void Glass::nextStep(QString text)
{
    if(_haveProgress) progressBar->setValue(progressBar->value()+1);
    if(_haveMessage) setMessage(text);
    qApp->processEvents();
}

void Glass::infinitely(QString text)
{
    qDebug() << _haveProgress << _haveMessage;
    if(!_haveProgress)
    {
        progressBar = new QProgressBar(0);
        progressBar->hide();
        progressBar->setObjectName(QString::fromUtf8("progressBar"));
        progressBar->setValue(0);
        progressBar->setMaximum(0);
        progressBar->setAlignment(Qt::AlignCenter);
        progressBar->setTextVisible(false);
        progressBar->setOrientation(Qt::Horizontal);
        progressBar->setInvertedAppearance(false);
        progressBar->setParent(_parent);
    }
    progressBar->setMinimum(0);
    progressBar->setMaximum(0);
    progressBar->startTimer(0);
    if(!_haveMessage)
    {
        infoText = new QLabel(0);
        infoText->hide();
        infoText->setAlignment(Qt::AlignCenter);
        infoText->setWordWrap(true);
        infoText->setStyleSheet("color:#fff;");
        infoText->setParent(_parent);
    }
    infoText->setText(text);
    infoText->show();
    progressBar->show();
    _haveProgress = true;
    _haveMessage = true;
    positioning();
}

    // например, в слоте для QPushButton::clicked()
    ...
    Glass *glass = new Glass("Step #1", 152);
    glass->setAnimationDuration(200);
    connect(glass, SIGNAL(initailized(int)), this, SLOT(steps(int)));
    glass->init(qobject_cast<QWidget *>(sender()->parent()));
    ...

void MainWindow::steps(int steps)
{
    Glass *glass = qobject_cast<Glass *>(sender());
    if(steps > 0)
    {
        QTime time;
        time.start();
        for(int i=0; i<steps; )
        {
            if(time.elapsed() > 20)
            {
                time.start();
                ++i;
                glass->nextStep(QString("Step #%1").arg(i+1));
            }
        }
    }
    else
    {
        QTime time;
        time.start();
        glass->infinitely("loading...");
        while(time.elapsed() < 5000)
        {
            qApp->processEvents();
        }
    }
    glass->hideAndDelete();
}