blurpicker.cpp Example File

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 #include "blurpicker.h"

 #include <QtWidgets>

 #include "blureffect.h"

 #ifndef M_PI
 #define M_PI 3.14159265358979323846
 #endif

 BlurPicker::BlurPicker(QWidget *parent): QGraphicsView(parent), m_index(0.0), m_animation(this, "index")
 {
     setBackgroundBrush(QPixmap(":/images/background.jpg"));
     setScene(new QGraphicsScene(this));

     setupScene();
     setIndex(0);

     m_animation.setDuration(400);
     m_animation.setEasingCurve(QEasingCurve::InOutSine);

     setRenderHint(QPainter::Antialiasing, true);
     setFrameStyle(QFrame::NoFrame);
 }

 qreal BlurPicker::index() const
 {
     return m_index;
 }

 void BlurPicker::setIndex(qreal index)
 {
     m_index = index;

     qreal baseline = 0;
     for (int i = 0; i < m_icons.count(); ++i) {
         QGraphicsItem *icon = m_icons[i];
         qreal a = ((i + m_index) * 2 * M_PI) / m_icons.count();
         qreal xs = 170 * sin(a);
         qreal ys = 100 * cos(a);
         QPointF pos(xs, ys);
         pos = QTransform().rotate(-20).map(pos);
         pos -= QPointF(40, 40);
         icon->setPos(pos);
         baseline = qMax(baseline, ys);
         static_cast<BlurEffect *>(icon->graphicsEffect())->setBaseLine(baseline);
     }

     scene()->update();
 }

 void BlurPicker::setupScene()
 {
     scene()->setSceneRect(-200, -120, 400, 240);

     QStringList names;
     names << ":/images/accessories-calculator.png";
     names << ":/images/accessories-text-editor.png";
     names << ":/images/help-browser.png";
     names << ":/images/internet-group-chat.png";
     names << ":/images/internet-mail.png";
     names << ":/images/internet-web-browser.png";
     names << ":/images/office-calendar.png";
     names << ":/images/system-users.png";

     for (int i = 0; i < names.count(); i++) {
         QPixmap pixmap(names[i]);
         QGraphicsPixmapItem *icon = scene()->addPixmap(pixmap);
         icon->setZValue(1);
         icon->setGraphicsEffect(new BlurEffect(icon));
         m_icons << icon;
     }

     QGraphicsPixmapItem *bg = scene()->addPixmap(QPixmap(":/images/background.jpg"));
     bg->setZValue(0);
     bg->setPos(-200, -150);
 }

 void BlurPicker::keyPressEvent(QKeyEvent *event)
 {
     int delta = 0;
     switch (event->key())
     {
     case Qt::Key_Left:
         delta = -1;
         break;
     case  Qt::Key_Right:
         delta = 1;
         break;
     default:
         break;
     }
     if (m_animation.state() == QAbstractAnimation::Stopped && delta) {
         m_animation.setEndValue(m_index + delta);
         m_animation.start();
         event->accept();
     }
 }

 void BlurPicker::resizeEvent(QResizeEvent */*event*/)
 {
 }

 void BlurPicker::mousePressEvent(QMouseEvent *event)
 {
     int delta = 0;
     if(event->x() > (width() / 2))
     {
         delta = 1;
     }
     else
     {
         delta = -1;
     }

     if (m_animation.state() == QAbstractAnimation::Stopped && delta) {
         m_animation.setEndValue(m_index + delta);
         m_animation.start();
         event->accept();
     }
 }