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50
51#include "puzzlewidget.h"
52#include "pieceslist.h"
53
54#include <QDrag>
55#include <QDragEnterEvent>
56#include <QMimeData>
57#include <QPainter>
58
59PuzzleWidget::PuzzleWidget(int imageSize, QWidget *parent)
60 : QWidget(parent), m_ImageSize(imageSize)
61{
62 setAcceptDrops(true);
63 setMinimumSize(minw: m_ImageSize, minh: m_ImageSize);
64 setMaximumSize(maxw: m_ImageSize, maxh: m_ImageSize);
65}
66
67void PuzzleWidget::clear()
68{
69 pieces.clear();
70 highlightedRect = QRect();
71 inPlace = 0;
72 update();
73}
74
75void PuzzleWidget::dragEnterEvent(QDragEnterEvent *event)
76{
77 if (event->mimeData()->hasFormat(mimetype: PiecesList::puzzleMimeType()))
78 event->accept();
79 else
80 event->ignore();
81}
82
83void PuzzleWidget::dragLeaveEvent(QDragLeaveEvent *event)
84{
85 QRect updateRect = highlightedRect;
86 highlightedRect = QRect();
87 update(updateRect);
88 event->accept();
89}
90
91void PuzzleWidget::dragMoveEvent(QDragMoveEvent *event)
92{
93 QRect updateRect = highlightedRect.united(r: targetSquare(position: event->pos()));
94
95 if (event->mimeData()->hasFormat(mimetype: PiecesList::puzzleMimeType())
96 && findPiece(pieceRect: targetSquare(position: event->pos())) == -1) {
97
98 highlightedRect = targetSquare(position: event->pos());
99 event->setDropAction(Qt::MoveAction);
100 event->accept();
101 } else {
102 highlightedRect = QRect();
103 event->ignore();
104 }
105
106 update(updateRect);
107}
108
109void PuzzleWidget::dropEvent(QDropEvent *event)
110{
111 if (event->mimeData()->hasFormat(mimetype: PiecesList::puzzleMimeType())
112 && findPiece(pieceRect: targetSquare(position: event->pos())) == -1) {
113
114 QByteArray pieceData = event->mimeData()->data(mimetype: PiecesList::puzzleMimeType());
115 QDataStream dataStream(&pieceData, QIODevice::ReadOnly);
116 Piece piece;
117 piece.rect = targetSquare(position: event->pos());
118 dataStream >> piece.pixmap >> piece.location;
119
120 pieces.append(t: piece);
121
122 highlightedRect = QRect();
123 update(piece.rect);
124
125 event->setDropAction(Qt::MoveAction);
126 event->accept();
127
128 if (piece.location == piece.rect.topLeft() / pieceSize()) {
129 inPlace++;
130 if (inPlace == 25)
131 emit puzzleCompleted();
132 }
133 } else {
134 highlightedRect = QRect();
135 event->ignore();
136 }
137}
138
139int PuzzleWidget::findPiece(const QRect &pieceRect) const
140{
141 for (int i = 0, size = pieces.size(); i < size; ++i) {
142 if (pieces.at(i).rect == pieceRect)
143 return i;
144 }
145 return -1;
146}
147
148void PuzzleWidget::mousePressEvent(QMouseEvent *event)
149{
150 QRect square = targetSquare(position: event->pos());
151 const int found = findPiece(pieceRect: square);
152
153 if (found == -1)
154 return;
155
156 Piece piece = pieces.takeAt(i: found);
157
158 if (piece.location == square.topLeft() / pieceSize())
159 inPlace--;
160
161 update(square);
162
163 QByteArray itemData;
164 QDataStream dataStream(&itemData, QIODevice::WriteOnly);
165
166 dataStream << piece.pixmap << piece.location;
167
168 QMimeData *mimeData = new QMimeData;
169 mimeData->setData(mimetype: PiecesList::puzzleMimeType(), data: itemData);
170
171 QDrag *drag = new QDrag(this);
172 drag->setMimeData(mimeData);
173 drag->setHotSpot(event->pos() - square.topLeft());
174 drag->setPixmap(piece.pixmap);
175
176 if (drag->exec(supportedActions: Qt::MoveAction) != Qt::MoveAction) {
177 pieces.insert(i: found, t: piece);
178 update(targetSquare(position: event->pos()));
179
180 if (piece.location == square.topLeft() / pieceSize())
181 inPlace++;
182 }
183}
184
185void PuzzleWidget::paintEvent(QPaintEvent *event)
186{
187 QPainter painter(this);
188 painter.fillRect(r: event->rect(), c: Qt::white);
189
190 if (highlightedRect.isValid()) {
191 painter.setBrush(QColor("#ffcccc"));
192 painter.setPen(Qt::NoPen);
193 painter.drawRect(r: highlightedRect.adjusted(xp1: 0, yp1: 0, xp2: -1, yp2: -1));
194 }
195
196 for (const Piece &piece : pieces)
197 painter.drawPixmap(r: piece.rect, pm: piece.pixmap);
198}
199
200const QRect PuzzleWidget::targetSquare(const QPoint &position) const
201{
202 return QRect(position / pieceSize() * pieceSize(),
203 QSize(pieceSize(), pieceSize()));
204}
205
206int PuzzleWidget::pieceSize() const
207{
208 return m_ImageSize / 5;
209}
210
211int PuzzleWidget::imageSize() const
212{
213 return m_ImageSize;
214}
215

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