- Qt 5.5
- Qt Widgets
- Drag and Drop Robot Example
- robot.cpp Example File
- Qt 5.5.1 Reference Documentation

# robot.cpp Example File

graphicsview/dragdroprobot/robot.cpp

    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
    ** You may use this file under the terms of the BSD license as follows:
    **
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    **     from this software without specific prior written permission.
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    #include <QtWidgets>

    #include "robot.h"

    RobotPart::RobotPart(QGraphicsItem *parent)
        : QGraphicsObject(parent), color(Qt::lightGray), dragOver(false)
    {
        setAcceptDrops(true);
    }

    void RobotPart::dragEnterEvent(QGraphicsSceneDragDropEvent *event)
    {
        if (event->mimeData()->hasColor()) {
            event->setAccepted(true);
            dragOver = true;
            update();
        } else {
            event->setAccepted(false);
        }
    }

    void RobotPart::dragLeaveEvent(QGraphicsSceneDragDropEvent *event)
    {
        Q_UNUSED(event);
        dragOver = false;
        update();
    }

    void RobotPart::dropEvent(QGraphicsSceneDragDropEvent *event)
    {
        dragOver = false;
        if (event->mimeData()->hasColor())
            color = qvariant_cast<QColor>(event->mimeData()->colorData());
        update();
    }

    RobotHead::RobotHead(QGraphicsItem *parent)
        : RobotPart(parent)
    {
    }

    QRectF RobotHead::boundingRect() const
    {
        return QRectF(-15, -50, 30, 50);
    }

    void RobotHead::paint(QPainter *painter,
               const QStyleOptionGraphicsItem *option, QWidget *widget)
    {
        Q_UNUSED(option);
        Q_UNUSED(widget);
        if (pixmap.isNull()) {
            painter->setBrush(dragOver ? color.light(130) : color);
            painter->drawRoundedRect(-10, -30, 20, 30, 25, 25, Qt::RelativeSize);
            painter->setBrush(Qt::white);
            painter->drawEllipse(-7, -3 - 20, 7, 7);
            painter->drawEllipse(0, -3 - 20, 7, 7);
            painter->setBrush(Qt::black);
            painter->drawEllipse(-5, -1 - 20, 2, 2);
            painter->drawEllipse(2, -1 - 20, 2, 2);
            painter->setPen(QPen(Qt::black, 2));
            painter->setBrush(Qt::NoBrush);
            painter->drawArc(-6, -2 - 20, 12, 15, 190 * 16, 160 * 16);
        } else {
            painter->scale(.2272, .2824);
            painter->drawPixmap(QPointF(-15 * 4.4, -50 * 3.54), pixmap);
        }
    }

    void RobotHead::dragEnterEvent(QGraphicsSceneDragDropEvent *event)
    {
        if (event->mimeData()->hasImage()) {
            event->setAccepted(true);
            dragOver = true;
            update();
        } else {
            RobotPart::dragEnterEvent(event);
        }
    }

    void RobotHead::dropEvent(QGraphicsSceneDragDropEvent *event)
    {
        if (event->mimeData()->hasImage()) {
            dragOver = false;
            pixmap = qvariant_cast<QPixmap>(event->mimeData()->imageData());
            update();
        } else {
            RobotPart::dropEvent(event);
        }
    }

    RobotTorso::RobotTorso(QGraphicsItem *parent)
        : RobotPart(parent)
    {
    }

    QRectF RobotTorso::boundingRect() const
    {
        return QRectF(-30, -20, 60, 60);
    }

    void RobotTorso::paint(QPainter *painter,
               const QStyleOptionGraphicsItem *option, QWidget *widget)
    {
        Q_UNUSED(option);
        Q_UNUSED(widget);

        painter->setBrush(dragOver ? color.light(130) : color);
        painter->drawRoundedRect(-20, -20, 40, 60, 25, 25, Qt::RelativeSize);
        painter->drawEllipse(-25, -20, 20, 20);
        painter->drawEllipse(5, -20, 20, 20);
        painter->drawEllipse(-20, 22, 20, 20);
        painter->drawEllipse(0, 22, 20, 20);
    }

    RobotLimb::RobotLimb(QGraphicsItem *parent)
        : RobotPart(parent)
    {
    }

    QRectF RobotLimb::boundingRect() const
    {
        return QRectF(-5, -5, 40, 10);
    }

    void RobotLimb::paint(QPainter *painter,
               const QStyleOptionGraphicsItem *option, QWidget *widget)
    {
        Q_UNUSED(option);
        Q_UNUSED(widget);

        painter->setBrush(dragOver ? color.light(130) : color);
        painter->drawRoundedRect(boundingRect(), 50, 50, Qt::RelativeSize);
        painter->drawEllipse(-5, -5, 10, 10);
    }

    Robot::Robot(QGraphicsItem *parent)
        : RobotPart(parent)
    {
        setFlag(ItemHasNoContents);

        QGraphicsObject *torsoItem = new RobotTorso(this);
        QGraphicsObject *headItem = new RobotHead(torsoItem);
        QGraphicsObject *upperLeftArmItem = new RobotLimb(torsoItem);
        QGraphicsObject *lowerLeftArmItem = new RobotLimb(upperLeftArmItem);
        QGraphicsObject *upperRightArmItem = new RobotLimb(torsoItem);
        QGraphicsObject *lowerRightArmItem = new RobotLimb(upperRightArmItem);
        QGraphicsObject *upperRightLegItem = new RobotLimb(torsoItem);
        QGraphicsObject *lowerRightLegItem = new RobotLimb(upperRightLegItem);
        QGraphicsObject *upperLeftLegItem = new RobotLimb(torsoItem);
        QGraphicsObject *lowerLeftLegItem = new RobotLimb(upperLeftLegItem);

        headItem->setPos(0, -18);
        upperLeftArmItem->setPos(-15, -10);
        lowerLeftArmItem->setPos(30, 0);
        upperRightArmItem->setPos(15, -10);
        lowerRightArmItem->setPos(30, 0);
        upperRightLegItem->setPos(10, 32);
        lowerRightLegItem->setPos(30, 0);
        upperLeftLegItem->setPos(-10, 32);
        lowerLeftLegItem->setPos(30, 0);

        QParallelAnimationGroup *animation = new QParallelAnimationGroup(this);

        QPropertyAnimation *headAnimation = new QPropertyAnimation(headItem, "rotation");
        headAnimation->setStartValue(20);
        headAnimation->setEndValue(-20);
        QPropertyAnimation *headScaleAnimation = new QPropertyAnimation(headItem, "scale");
        headScaleAnimation->setEndValue(1.1);
        animation->addAnimation(headAnimation);
        animation->addAnimation(headScaleAnimation);

        QPropertyAnimation *upperLeftArmAnimation = new QPropertyAnimation(upperLeftArmItem, "rotation");
        upperLeftArmAnimation->setStartValue(190);
        upperLeftArmAnimation->setEndValue(180);
        animation->addAnimation(upperLeftArmAnimation);

        QPropertyAnimation *lowerLeftArmAnimation = new QPropertyAnimation(lowerLeftArmItem, "rotation");
        lowerLeftArmAnimation->setStartValue(50);
        lowerLeftArmAnimation->setEndValue(10);
        animation->addAnimation(lowerLeftArmAnimation);

        QPropertyAnimation *upperRightArmAnimation = new QPropertyAnimation(upperRightArmItem, "rotation");
        upperRightArmAnimation->setStartValue(300);
        upperRightArmAnimation->setEndValue(310);
        animation->addAnimation(upperRightArmAnimation);

        QPropertyAnimation *lowerRightArmAnimation = new QPropertyAnimation(lowerRightArmItem, "rotation");
        lowerRightArmAnimation->setStartValue(0);
        lowerRightArmAnimation->setEndValue(-70);
        animation->addAnimation(lowerRightArmAnimation);

        QPropertyAnimation *upperLeftLegAnimation = new QPropertyAnimation(upperLeftLegItem, "rotation");
        upperLeftLegAnimation->setStartValue(150);
        upperLeftLegAnimation->setEndValue(80);
        animation->addAnimation(upperLeftLegAnimation);

        QPropertyAnimation *lowerLeftLegAnimation = new QPropertyAnimation(lowerLeftLegItem, "rotation");
        lowerLeftLegAnimation->setStartValue(70);
        lowerLeftLegAnimation->setEndValue(10);
        animation->addAnimation(lowerLeftLegAnimation);

        QPropertyAnimation *upperRightLegAnimation = new QPropertyAnimation(upperRightLegItem, "rotation");
        upperRightLegAnimation->setStartValue(40);
        upperRightLegAnimation->setEndValue(120);
        animation->addAnimation(upperRightLegAnimation);

        QPropertyAnimation *lowerRightLegAnimation = new QPropertyAnimation(lowerRightLegItem, "rotation");
        lowerRightLegAnimation->setStartValue(10);
        lowerRightLegAnimation->setEndValue(50);
        animation->addAnimation(lowerRightLegAnimation);

        QPropertyAnimation *torsoAnimation = new QPropertyAnimation(torsoItem, "rotation");
        torsoAnimation->setStartValue(5);
        torsoAnimation->setEndValue(-20);
        animation->addAnimation(torsoAnimation);

        for (int i = 0; i < animation->animationCount(); ++i) {
            QPropertyAnimation *anim = qobject_cast<QPropertyAnimation *>(animation->animationAt(i));
            anim->setEasingCurve(QEasingCurve::SineCurve);
            anim->setDuration(2000);
        }

        animation->setLoopCount(-1);
        animation->start();
    }

    QRectF Robot::boundingRect() const
    {
        return QRectF();
    }

    void Robot::paint(QPainter *painter,
                      const QStyleOptionGraphicsItem *option, QWidget *widget)
    {
        Q_UNUSED(painter);
        Q_UNUSED(option);
        Q_UNUSED(widget);
    }