puzzlewidget.cpp Example File
draganddrop/puzzle/puzzlewidget.cpp
/****************************************************************************
**
** Copyright (C) 2005-2005 Trolltech AS. All rights reserved.
**
** This file is part of the documentation of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file. Please review the following information to ensure GNU
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** review the following information:
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** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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****************************************************************************/
#include <QtGui>
#include "puzzlewidget.h"
PuzzleWidget::PuzzleWidget(QWidget *parent)
: QWidget(parent)
{
setAcceptDrops(true);
setMinimumSize(400, 400);
setMaximumSize(400, 400);
}
void PuzzleWidget::clear()
{
pieceLocations.clear();
piecePixmaps.clear();
pieceRects.clear();
highlightedRect = QRect();
inPlace = 0;
update();
}
void PuzzleWidget::dragEnterEvent(QDragEnterEvent *event)
{
if (event->mimeData()->hasFormat("image/x-puzzle-piece"))
event->accept();
else
event->ignore();
}
void PuzzleWidget::dragLeaveEvent(QDragLeaveEvent *event)
{
QRect updateRect = highlightedRect;
highlightedRect = QRect();
update(updateRect);
event->accept();
}
void PuzzleWidget::dragMoveEvent(QDragMoveEvent *event)
{
QRect updateRect = highlightedRect.unite(targetSquare(event->pos()));
if (event->mimeData()->hasFormat("image/x-puzzle-piece")
&& findPiece(targetSquare(event->pos())) == -1) {
highlightedRect = targetSquare(event->pos());
event->setDropAction(Qt::MoveAction);
event->accept();
} else {
highlightedRect = QRect();
event->ignore();
}
update(updateRect);
}
void PuzzleWidget::dropEvent(QDropEvent *event)
{
if (event->mimeData()->hasFormat("image/x-puzzle-piece")
&& findPiece(targetSquare(event->pos())) == -1) {
QByteArray pieceData = event->mimeData()->data("image/x-puzzle-piece");
QDataStream dataStream(&pieceData, QIODevice::ReadOnly);
QRect square = targetSquare(event->pos());
QPixmap pixmap;
QPoint location;
dataStream >> pixmap >> location;
pieceLocations.append(location);
piecePixmaps.append(pixmap);
pieceRects.append(square);
highlightedRect = QRect();
update(square);
event->setDropAction(Qt::MoveAction);
event->accept();
if (location == QPoint(square.x()/80, square.y()/80)) {
inPlace++;
if (inPlace == 25)
emit puzzleCompleted();
}
} else {
highlightedRect = QRect();
event->ignore();
}
}
int PuzzleWidget::findPiece(const QRect &pieceRect) const
{
for (int i = 0; i < pieceRects.size(); ++i) {
if (pieceRect == pieceRects[i]) {
return i;
}
}
return -1;
}
void PuzzleWidget::mousePressEvent(QMouseEvent *event)
{
QRect square = targetSquare(event->pos());
int found = findPiece(square);
if (found == -1)
return;
QPoint location = pieceLocations[found];
QPixmap pixmap = piecePixmaps[found];
pieceLocations.removeAt(found);
piecePixmaps.removeAt(found);
pieceRects.removeAt(found);
if (location == QPoint(square.x()/80, square.y()/80))
inPlace--;
update(square);
QByteArray itemData;
QDataStream dataStream(&itemData, QIODevice::WriteOnly);
dataStream << pixmap << location;
QMimeData *mimeData = new QMimeData;
mimeData->setData("image/x-puzzle-piece", itemData);
QDrag *drag = new QDrag(this);
drag->setMimeData(mimeData);
drag->setHotSpot(event->pos() - square.topLeft());
drag->setPixmap(pixmap);
if (!(drag->start(Qt::MoveAction) == Qt::MoveAction)) {
pieceLocations.insert(found, location);
piecePixmaps.insert(found, pixmap);
pieceRects.insert(found, square);
update(targetSquare(event->pos()));
if (location == QPoint(square.x()/80, square.y()/80))
inPlace++;
}
}
void PuzzleWidget::paintEvent(QPaintEvent *event)
{
QPainter painter;
painter.begin(this);
painter.fillRect(event->rect(), Qt::white);
if (highlightedRect.isValid()) {
painter.setBrush(QColor("#ffcccc"));
painter.setPen(Qt::NoPen);
painter.drawRect(highlightedRect.adjusted(0, 0, -1, -1));
}
for (int i = 0; i < pieceRects.size(); ++i) {
painter.drawPixmap(pieceRects[i], piecePixmaps[i]);
}
painter.end();
}
const QRect PuzzleWidget::targetSquare(const QPoint &position) const
{
return QRect(position.x()/80 * 80, position.y()/80 * 80, 80, 80);
}