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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "coloritem.h"
#include <QApplication>
#include <QBitmap>
#include <QCursor>
#include <QDrag>
#include <QGraphicsSceneMouseEvent>
#include <QMimeData>
#include <QPainter>
#include <QRandomGenerator>
#include <QWidget>
//! [0]
ColorItem::ColorItem()
: color(QRandomGenerator::global()->bounded(256), QRandomGenerator::global()->bounded(256), QRandomGenerator::global()->bounded(256))
{
setToolTip(QString("QColor(%1, %2, %3)\n%4")
.arg(color.red()).arg(color.green()).arg(color.blue())
.arg("Click and drag this color onto the robot!"));
setCursor(Qt::OpenHandCursor);
setAcceptedMouseButtons(Qt::LeftButton);
}
//! [0]
//! [1]
QRectF ColorItem::boundingRect() const
{
return QRectF(-15.5, -15.5, 34, 34);
}
//! [1]
//! [2]
void ColorItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
Q_UNUSED(option);
Q_UNUSED(widget);
painter->setPen(Qt::NoPen);
painter->setBrush(Qt::darkGray);
painter->drawEllipse(-12, -12, 30, 30);
painter->setPen(QPen(Qt::black, 1));
painter->setBrush(QBrush(color));
painter->drawEllipse(-15, -15, 30, 30);
}
//! [2]
//! [3]
void ColorItem::mousePressEvent(QGraphicsSceneMouseEvent *)
{
setCursor(Qt::ClosedHandCursor);
}
//! [3]
//! [5]
void ColorItem::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
{
if (QLineF(event->screenPos(), event->buttonDownScreenPos(Qt::LeftButton))
.length() < QApplication::startDragDistance()) {
return;
}
QDrag *drag = new QDrag(event->widget());
QMimeData *mime = new QMimeData;
drag->setMimeData(mime);
//! [5]
//! [6]
static int n = 0;
if (n++ > 2 && QRandomGenerator::global()->bounded(3) == 0) {
QImage image(":/images/head.png");
mime->setImageData(image);
drag->setPixmap(QPixmap::fromImage(image).scaled(30, 40));
drag->setHotSpot(QPoint(15, 30));
//! [6]
//! [7]
} else {
mime->setColorData(color);
mime->setText(QString("#%1%2%3")
.arg(color.red(), 2, 16, QLatin1Char('0'))
.arg(color.green(), 2, 16, QLatin1Char('0'))
.arg(color.blue(), 2, 16, QLatin1Char('0')));
QPixmap pixmap(34, 34);
pixmap.fill(Qt::white);
QPainter painter(&pixmap);
painter.translate(15, 15);
painter.setRenderHint(QPainter::Antialiasing);
paint(&painter, nullptr, nullptr);
painter.end();
pixmap.setMask(pixmap.createHeuristicMask());
drag->setPixmap(pixmap);
drag->setHotSpot(QPoint(15, 20));
}
//! [7]
//! [8]
drag->exec();
setCursor(Qt::OpenHandCursor);
}
//! [8]
//! [4]
void ColorItem::mouseReleaseEvent(QGraphicsSceneMouseEvent *)
{
setCursor(Qt::OpenHandCursor);
}
//! [4]
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