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50
51 #include "pieceslist.h"
52
53 #include <QDrag>
54 #include <QDragEnterEvent>
55 #include <QMimeData>
56
PiecesList(int pieceSize,QWidget * parent)57 PiecesList::PiecesList(int pieceSize, QWidget *parent)
58 : QListWidget(parent), m_PieceSize(pieceSize)
59 {
60 setDragEnabled(true);
61 setViewMode(QListView::IconMode);
62 setIconSize(QSize(m_PieceSize, m_PieceSize));
63 setSpacing(10);
64 setAcceptDrops(true);
65 setDropIndicatorShown(true);
66 }
67
dragEnterEvent(QDragEnterEvent * event)68 void PiecesList::dragEnterEvent(QDragEnterEvent *event)
69 {
70 if (event->mimeData()->hasFormat(PiecesList::puzzleMimeType()))
71 event->accept();
72 else
73 event->ignore();
74 }
75
dragMoveEvent(QDragMoveEvent * event)76 void PiecesList::dragMoveEvent(QDragMoveEvent *event)
77 {
78 if (event->mimeData()->hasFormat(PiecesList::puzzleMimeType())) {
79 event->setDropAction(Qt::MoveAction);
80 event->accept();
81 } else {
82 event->ignore();
83 }
84 }
85
dropEvent(QDropEvent * event)86 void PiecesList::dropEvent(QDropEvent *event)
87 {
88 if (event->mimeData()->hasFormat(PiecesList::puzzleMimeType())) {
89 QByteArray pieceData = event->mimeData()->data(PiecesList::puzzleMimeType());
90 QDataStream dataStream(&pieceData, QIODevice::ReadOnly);
91 QPixmap pixmap;
92 QPoint location;
93 dataStream >> pixmap >> location;
94
95 addPiece(pixmap, location);
96
97 event->setDropAction(Qt::MoveAction);
98 event->accept();
99 } else {
100 event->ignore();
101 }
102 }
103
addPiece(const QPixmap & pixmap,const QPoint & location)104 void PiecesList::addPiece(const QPixmap &pixmap, const QPoint &location)
105 {
106 QListWidgetItem *pieceItem = new QListWidgetItem(this);
107 pieceItem->setIcon(QIcon(pixmap));
108 pieceItem->setData(Qt::UserRole, QVariant(pixmap));
109 pieceItem->setData(Qt::UserRole+1, location);
110 pieceItem->setFlags(Qt::ItemIsEnabled | Qt::ItemIsSelectable | Qt::ItemIsDragEnabled);
111 }
112
startDrag(Qt::DropActions)113 void PiecesList::startDrag(Qt::DropActions /*supportedActions*/)
114 {
115 QListWidgetItem *item = currentItem();
116
117 QByteArray itemData;
118 QDataStream dataStream(&itemData, QIODevice::WriteOnly);
119 QPixmap pixmap = qvariant_cast<QPixmap>(item->data(Qt::UserRole));
120 QPoint location = item->data(Qt::UserRole+1).toPoint();
121
122 dataStream << pixmap << location;
123
124 QMimeData *mimeData = new QMimeData;
125 mimeData->setData(PiecesList::puzzleMimeType(), itemData);
126
127 QDrag *drag = new QDrag(this);
128 drag->setMimeData(mimeData);
129 drag->setHotSpot(QPoint(pixmap.width()/2, pixmap.height()/2));
130 drag->setPixmap(pixmap);
131
132 if (drag->exec(Qt::MoveAction) == Qt::MoveAction)
133 delete takeItem(row(item));
134 }
135