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# Code for Fridge Magnets Example

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    package com.trolltech.examples;

    import com.trolltech.qt.core.*;
    import com.trolltech.qt.gui.*;

    @QtJambiExample(name = "Drag and Drop")
    public class FridgeMagnets extends QWidget {

        public static void main(String args[]) {
            QApplication.initialize(args);
            FridgeMagnets fridgeMagnets = new FridgeMagnets(null);
            fridgeMagnets.show();
            QApplication.exec();
        }

        public FridgeMagnets(QWidget parent) {
            super(parent);
            QFile dictionaryFile;
            dictionaryFile = new QFile("classpath:com/trolltech/examples/words.txt");
            dictionaryFile.open(QIODevice.OpenModeFlag.ReadOnly);
            QTextStream inputStream = new QTextStream(dictionaryFile);

            int x = 5;
            int y = 5;

            while (!inputStream.atEnd()) {
                String word = "";
                word = inputStream.readLine();
                if (!word.equals("")) {
                    DragLabel wordLabel = new DragLabel(word, this);
                    wordLabel.move(x, y);
                    wordLabel.show();
                    x += wordLabel.sizeHint().width() + 2;
                    if (x >= 245) {
                        x = 5;
                        y += wordLabel.sizeHint().height() + 2;
                    }
                }
            }
            inputStream.dispose();
            dictionaryFile.dispose();

            QPalette newPalette = palette();
            newPalette.setColor(QPalette.ColorRole.Window, QColor.white);
            setPalette(newPalette);

            setMinimumSize(400, Math.max(200, y));
            setWindowIcon(new QIcon("classpath:com/trolltech/images/qt-logo.png"));
            setWindowTitle(tr("Fridge Magnets"));

            setAcceptDrops(true);
        }

        @Override
        public void dragEnterEvent(QDragEnterEvent event) {
            if (event.mimeData().hasFormat("application/x-fridgemagnet")) {
                if (children().contains(event.source())) {
                    event.setDropAction(Qt.DropAction.MoveAction);
                    event.accept();
                } else {
                    event.acceptProposedAction();
                }
            } else if (event.mimeData().hasText()) {
                event.acceptProposedAction();
            } else {
                event.ignore();
            }
        }

        @Override
        public void dragMoveEvent(QDragMoveEvent event) {
            if (event.mimeData().hasFormat("application/x-fridgemagnet")) {
                if (children().contains(event.source())) {
                    event.setDropAction(Qt.DropAction.MoveAction);
                    event.accept();
                } else {
                    event.acceptProposedAction();
                }
            } else if (event.mimeData().hasText()) {
                event.acceptProposedAction();
            } else {
                event.ignore();
            }
        }

        @Override
        public void dropEvent(QDropEvent event) {
            if (event.mimeData().hasFormat("application/x-fridgemagnet")) {
                com.trolltech.qt.core.QMimeData mime = event.mimeData();
                QByteArray itemData = mime.data("application/x-fridgemagnet");
                QDataStream dataStream = new QDataStream(itemData,
                       new QIODevice.OpenMode(QIODevice.OpenModeFlag.ReadOnly));

                String text = dataStream.readString();
                QPoint offset = new QPoint();
                offset.readFrom(dataStream);

                DragLabel newLabel = new DragLabel(text, this);
                newLabel.move(new QPoint(event.pos().x() - offset.x(),
                                         event.pos().y() - offset.y()));
                newLabel.show();

                if (children().contains(event.source())) {
                    event.setDropAction(Qt.DropAction.MoveAction);
                    event.accept();
                } else {
                    event.acceptProposedAction();
                }
            } else if (event.mimeData().hasText()) {
                String[] pieces = event.mimeData().text().split("\\s+");
                QPoint position = event.pos();

                for (String piece : pieces) {
                    if (piece.equals(""))
                        continue;

                    DragLabel newLabel = new DragLabel(piece, this);
                    newLabel.move(position);
                    newLabel.show();

                    position.add(new QPoint(newLabel.width(), 0));
                }

                event.acceptProposedAction();
            } else {
                event.ignore();
            }
        }

        class DragLabel extends QLabel {
            private String labelText;

            public DragLabel(final String text, QWidget parent) {
                super(parent);

                QFontMetrics metrics = new QFontMetrics(font());
                QSize size = metrics.size(12, text);
                QImage image = new QImage(size.width() + 12, size.height() + 12,
                        QImage.Format.Format_ARGB32_Premultiplied);
                image.fill(0);

                QFont font = new QFont();
                font.setStyleStrategy(QFont.StyleStrategy.ForceOutline);

                QPainter painter = new QPainter();
                painter.begin(image);
                painter.setRenderHint(QPainter.RenderHint.Antialiasing);
                painter.setBrush(QColor.white);
                QRectF frame = new QRectF(0.5, 0.5, image.width() - 1,
                                          image.height() - 1);
                painter.drawRoundRect(frame, 10 * 100 / image.width(), 10 * 100 / image.height());

                painter.setFont(font);
                painter.setBrush(QColor.black);

                QRect rectangle = new QRect(new QPoint(6, 6), size);
                painter.drawText(rectangle, Qt.AlignmentFlag.AlignCenter.value(),
                                 text);
                painter.end();

                setPixmap(QPixmap.fromImage(image));
                labelText = text;
            }

            @Override
            public void mousePressEvent(QMouseEvent event) {
                QByteArray itemData = new QByteArray();
                QDataStream dataStream;
                dataStream = new QDataStream(itemData,
                        new QIODevice.OpenMode(QIODevice.OpenModeFlag.WriteOnly));

                dataStream.writeString(labelText);
                QPoint position = new QPoint(event.pos().x() - rect().topLeft().x(),
                                             event.pos().y() - rect().topLeft().y());
                position.writeTo(dataStream);

                com.trolltech.qt.core.QMimeData mimeData = new com.trolltech.qt.core.QMimeData();
                mimeData.setData("application/x-fridgemagnet", itemData);
                mimeData.setText(labelText);

                QDrag drag = new QDrag(this);
                drag.setMimeData(mimeData);

                drag.setHotSpot(new QPoint(event.pos().x() - rect().topLeft().x(),
                                           event.pos().y() - rect().topLeft().y()));
                drag.setPixmap(pixmap());

                hide();

                if (drag.exec(Qt.DropAction.MoveAction) == Qt.DropAction.MoveAction)
                    close();
                else
                    show();
            }
        }
    }