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50
51#include "puzzlewidget.h"
52
53#include <QtWidgets>
54
55PuzzleWidget::PuzzleWidget(int imageSize, QWidget *parent)
56 : QWidget(parent), m_ImageSize(imageSize)
57{
58 setAcceptDrops(true);
59 setMinimumSize(minw: m_ImageSize, minh: m_ImageSize);
60 setMaximumSize(maxw: m_ImageSize, maxh: m_ImageSize);
61}
62
63void PuzzleWidget::clear()
64{
65 pieces.clear();
66 highlightedRect = QRect();
67 inPlace = 0;
68 update();
69}
70
71void PuzzleWidget::dragEnterEvent(QDragEnterEvent *event)
72{
73 if (event->mimeData()->hasFormat(mimetype: "image/x-puzzle-piece"))
74 event->accept();
75 else
76 event->ignore();
77}
78
79void PuzzleWidget::dragLeaveEvent(QDragLeaveEvent *event)
80{
81 QRect updateRect = highlightedRect;
82 highlightedRect = QRect();
83 update(updateRect);
84 event->accept();
85}
86
87void PuzzleWidget::dragMoveEvent(QDragMoveEvent *event)
88{
89 QRect updateRect = highlightedRect.united(r: targetSquare(position: event->pos()));
90
91 if (event->mimeData()->hasFormat(mimetype: "image/x-puzzle-piece")
92 && findPiece(pieceRect: targetSquare(position: event->pos())) == -1) {
93
94 highlightedRect = targetSquare(position: event->pos());
95 event->setDropAction(Qt::MoveAction);
96 event->accept();
97 } else {
98 highlightedRect = QRect();
99 event->ignore();
100 }
101
102 update(updateRect);
103}
104
105void PuzzleWidget::dropEvent(QDropEvent *event)
106{
107 if (event->mimeData()->hasFormat(mimetype: "image/x-puzzle-piece")
108 && findPiece(pieceRect: targetSquare(position: event->pos())) == -1) {
109
110 QByteArray pieceData = event->mimeData()->data(mimetype: "image/x-puzzle-piece");
111 QDataStream dataStream(&pieceData, QIODevice::ReadOnly);
112 Piece piece;
113 piece.rect = targetSquare(position: event->pos());
114 dataStream >> piece.pixmap >> piece.location;
115
116 pieces.append(t: piece);
117
118 highlightedRect = QRect();
119 update(piece.rect);
120
121 event->setDropAction(Qt::MoveAction);
122 event->accept();
123
124 if (piece.location == piece.rect.topLeft() / pieceSize()) {
125 inPlace++;
126 if (inPlace == 25)
127 emit puzzleCompleted();
128 }
129 } else {
130 highlightedRect = QRect();
131 event->ignore();
132 }
133}
134
135int PuzzleWidget::findPiece(const QRect &pieceRect) const
136{
137 for (int i = 0, size = pieces.size(); i < size; ++i) {
138 if (pieces.at(i).rect == pieceRect)
139 return i;
140 }
141 return -1;
142}
143
144void PuzzleWidget::mousePressEvent(QMouseEvent *event)
145{
146 QRect square = targetSquare(position: event->pos());
147 int found = findPiece(pieceRect: square);
148
149 if (found == -1)
150 return;
151
152 Piece piece = pieces.takeAt(i: found);
153
154 if (piece.location == square.topLeft() / pieceSize())
155 inPlace--;
156
157 update(square);
158
159 QByteArray itemData;
160 QDataStream dataStream(&itemData, QIODevice::WriteOnly);
161
162 dataStream << piece.pixmap << piece.location;
163
164 QMimeData *mimeData = new QMimeData;
165 mimeData->setData(mimetype: "image/x-puzzle-piece", data: itemData);
166
167 QDrag *drag = new QDrag(this);
168 drag->setMimeData(mimeData);
169 drag->setHotSpot(event->pos() - square.topLeft());
170 drag->setPixmap(piece.pixmap);
171
172 if (drag->exec(supportedActions: Qt::MoveAction) == Qt::IgnoreAction) {
173 pieces.insert(i: found, t: piece);
174 update(targetSquare(position: event->pos()));
175
176 if (piece.location == QPoint(square.x() / pieceSize(), square.y() / pieceSize()))
177 inPlace++;
178 }
179}
180
181void PuzzleWidget::paintEvent(QPaintEvent *event)
182{
183 QPainter painter(this);
184 painter.fillRect(r: event->rect(), c: Qt::white);
185
186 if (highlightedRect.isValid()) {
187 painter.setBrush(QColor("#ffcccc"));
188 painter.setPen(Qt::NoPen);
189 painter.drawRect(r: highlightedRect.adjusted(xp1: 0, yp1: 0, xp2: -1, yp2: -1));
190 }
191
192 for (const Piece &piece : pieces)
193 painter.drawPixmap(r: piece.rect, pm: piece.pixmap);
194}
195
196const QRect PuzzleWidget::targetSquare(const QPoint &position) const
197{
198 return QRect(position / pieceSize() * pieceSize(),
199 QSize(pieceSize(), pieceSize()));
200}
201
202int PuzzleWidget::pieceSize() const
203{
204 return m_ImageSize / 5;
205}
206
207int PuzzleWidget::imageSize() const
208{
209 return m_ImageSize;
210}
211

source code of qtbase/examples/widgets/itemviews/puzzle/puzzlewidget.cpp