| 1 | /**************************************************************************** | 
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| 2 | ** | 
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| 3 | ** Copyright (C) 2016 The Qt Company Ltd. | 
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| 4 | ** Contact: https://www.qt.io/licensing/ | 
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| 5 | ** | 
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| 6 | ** This file is part of the examples of the Qt Toolkit. | 
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| 7 | ** | 
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| 8 | ** $QT_BEGIN_LICENSE:BSD$ | 
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| 9 | ** Commercial License Usage | 
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| 10 | ** Licensees holding valid commercial Qt licenses may use this file in | 
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| 11 | ** accordance with the commercial license agreement provided with the | 
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| 12 | ** Software or, alternatively, in accordance with the terms contained in | 
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| 13 | ** a written agreement between you and The Qt Company. For licensing terms | 
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| 14 | ** and conditions see https://www.qt.io/terms-conditions. For further | 
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| 15 | ** information use the contact form at https://www.qt.io/contact-us. | 
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| 16 | ** | 
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| 17 | ** BSD License Usage | 
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| 18 | ** Alternatively, you may use this file under the terms of the BSD license | 
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| 19 | ** as follows: | 
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| 20 | ** | 
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| 21 | ** "Redistribution and use in source and binary forms, with or without | 
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| 22 | ** modification, are permitted provided that the following conditions are | 
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| 23 | ** met: | 
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| 24 | **   * Redistributions of source code must retain the above copyright | 
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| 25 | **     notice, this list of conditions and the following disclaimer. | 
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| 26 | **   * Redistributions in binary form must reproduce the above copyright | 
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| 27 | **     notice, this list of conditions and the following disclaimer in | 
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| 28 | **     the documentation and/or other materials provided with the | 
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| 29 | **     distribution. | 
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| 30 | **   * Neither the name of The Qt Company Ltd nor the names of its | 
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| 31 | **     contributors may be used to endorse or promote products derived | 
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| 32 | **     from this software without specific prior written permission. | 
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| 33 | ** | 
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| 34 | ** | 
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| 35 | ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | 
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| 36 | ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | 
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| 37 | ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | 
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| 38 | ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | 
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| 39 | ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | 
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| 40 | ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | 
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| 41 | ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | 
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| 42 | ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | 
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| 43 | ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | 
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| 44 | ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | 
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| 45 | ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." | 
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| 46 | ** | 
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| 47 | ** $QT_END_LICENSE$ | 
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| 48 | ** | 
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| 49 | ****************************************************************************/ | 
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| 50 |  | 
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| 51 | #include "coloritem.h" | 
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| 52 |  | 
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| 53 | #include <QApplication> | 
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| 54 | #include <QBitmap> | 
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| 55 | #include <QCursor> | 
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| 56 | #include <QDrag> | 
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| 57 | #include <QGraphicsSceneMouseEvent> | 
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| 58 | #include <QMimeData> | 
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| 59 | #include <QPainter> | 
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| 60 | #include <QRandomGenerator> | 
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| 61 | #include <QWidget> | 
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| 62 |  | 
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| 63 | //! [0] | 
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| 64 | ColorItem::ColorItem() | 
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| 65 | : color(QRandomGenerator::global()->bounded(256), QRandomGenerator::global()->bounded(256), QRandomGenerator::global()->bounded(256)) | 
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| 66 | { | 
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| 67 | setToolTip(QString( "QColor(%1, %2, %3)\n%4") | 
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| 68 | .arg(color.red()).arg(color.green()).arg(color.blue()) | 
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| 69 | .arg( "Click and drag this color onto the robot!")); | 
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| 70 | setCursor(Qt::OpenHandCursor); | 
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| 71 | setAcceptedMouseButtons(Qt::LeftButton); | 
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| 72 | } | 
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| 73 | //! [0] | 
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| 74 |  | 
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| 75 | //! [1] | 
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| 76 | QRectF ColorItem::boundingRect() const | 
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| 77 | { | 
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| 78 | return QRectF(-15.5, -15.5, 34, 34); | 
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| 79 | } | 
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| 80 | //! [1] | 
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| 81 |  | 
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| 82 | //! [2] | 
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| 83 | void ColorItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget) | 
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| 84 | { | 
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| 85 | Q_UNUSED(option); | 
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| 86 | Q_UNUSED(widget); | 
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| 87 | painter->setPen(Qt::NoPen); | 
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| 88 | painter->setBrush(Qt::darkGray); | 
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| 89 | painter->drawEllipse(-12, -12, 30, 30); | 
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| 90 | painter->setPen(QPen(Qt::black, 1)); | 
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| 91 | painter->setBrush(QBrush(color)); | 
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| 92 | painter->drawEllipse(-15, -15, 30, 30); | 
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| 93 | } | 
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| 94 | //! [2] | 
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| 95 |  | 
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| 96 | //! [3] | 
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| 97 | void ColorItem::mousePressEvent(QGraphicsSceneMouseEvent *) | 
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| 98 | { | 
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| 99 | setCursor(Qt::ClosedHandCursor); | 
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| 100 | } | 
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| 101 | //! [3] | 
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| 102 |  | 
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| 103 | //! [5] | 
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| 104 | void ColorItem::mouseMoveEvent(QGraphicsSceneMouseEvent *event) | 
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| 105 | { | 
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| 106 | if (QLineF(event->screenPos(), event->buttonDownScreenPos(Qt::LeftButton)) | 
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| 107 | .length() < QApplication::startDragDistance()) { | 
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| 108 | return; | 
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| 109 | } | 
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| 110 |  | 
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| 111 | QDrag *drag = new QDrag(event->widget()); | 
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| 112 | QMimeData *mime = new QMimeData; | 
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| 113 | drag->setMimeData(mime); | 
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| 114 | //! [5] | 
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| 115 |  | 
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| 116 | //! [6] | 
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| 117 | static int n = 0; | 
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| 118 | if (n++ > 2 && QRandomGenerator::global()->bounded(3) == 0) { | 
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| 119 | QImage image( ":/images/head.png"); | 
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| 120 | mime->setImageData(image); | 
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| 121 |  | 
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| 122 | drag->setPixmap(QPixmap::fromImage(image).scaled(30, 40)); | 
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| 123 | drag->setHotSpot(QPoint(15, 30)); | 
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| 124 | //! [6] | 
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| 125 | //! [7] | 
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| 126 | } else { | 
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| 127 | mime->setColorData(color); | 
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| 128 | mime->setText(QString( "#%1%2%3") | 
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| 129 | .arg(color.red(), 2, 16, QLatin1Char('0')) | 
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| 130 | .arg(color.green(), 2, 16, QLatin1Char('0')) | 
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| 131 | .arg(color.blue(), 2, 16, QLatin1Char('0'))); | 
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| 132 |  | 
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| 133 | QPixmap pixmap(34, 34); | 
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| 134 | pixmap.fill(Qt::white); | 
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| 135 |  | 
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| 136 | QPainter painter(&pixmap); | 
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| 137 | painter.translate(15, 15); | 
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| 138 | painter.setRenderHint(QPainter::Antialiasing); | 
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| 139 | paint(&painter, nullptr, nullptr); | 
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| 140 | painter.end(); | 
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| 141 |  | 
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| 142 | pixmap.setMask(pixmap.createHeuristicMask()); | 
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| 143 |  | 
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| 144 | drag->setPixmap(pixmap); | 
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| 145 | drag->setHotSpot(QPoint(15, 20)); | 
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| 146 | } | 
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| 147 | //! [7] | 
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| 148 |  | 
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| 149 | //! [8] | 
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| 150 | drag->exec(); | 
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| 151 | setCursor(Qt::OpenHandCursor); | 
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| 152 | } | 
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| 153 | //! [8] | 
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| 154 |  | 
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| 155 | //! [4] | 
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| 156 | void ColorItem::mouseReleaseEvent(QGraphicsSceneMouseEvent *) | 
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| 157 | { | 
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| 158 | setCursor(Qt::OpenHandCursor); | 
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| 159 | } | 
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| 160 | //! [4] | 
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| 161 |  | 
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