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# Code for Scribble Example

    /****************************************************************************
    **
    ** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
    **
    ** This file is part of Qt Jambi.
    **
    ** ** 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
    ** General Public Licensing requirements will be met:
    ** http://www.trolltech.com/products/qt/opensource.html
    **
    ** If you are unsure which license is appropriate for your use, please
    ** review the following information:
    ** http://www.trolltech.com/products/qt/licensing.html or contact the
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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.
    **
    ****************************************************************************/

    package com.trolltech.examples;

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

    import java.util.*;

    @QtJambiExample (name = "Scribble")
    public class Scribble extends QMainWindow
    {
        private ScribbleArea scribbleArea;

        private QMenu saveAsMenu;
        private QMenu fileMenu;
        private QMenu optionMenu;
        private QMenu helpMenu;

        private QAction openAct;
        private List<QAction> saveAsActs;
        private QAction exitAct;
        private QAction penColorAct;
        private QAction penWidthAct;
        private QAction printAct;
        private QAction clearScreenAct;
        private QAction aboutAct;
        private QAction aboutQtAct;

        public Scribble()
        {
            scribbleArea = new ScribbleArea();
            setCentralWidget(scribbleArea);

            createActions();
            createMenus();

            setWindowTitle(tr("Scribble"));
            resize(500, 500);
        }

        @Override
        protected void closeEvent(QCloseEvent event)
        {
            if (maybeSave()) {
                event.accept();
            } else {
                event.ignore();
            }
        }

        private void open()
        {
            if (maybeSave()) {
                String fileName = QFileDialog.getOpenFileName(this,
                                    tr("Open File"), QDir.currentPath());
            if (fileName.length() != 0)
                scribbleArea.openImage(fileName);
            }
        }

        private void save()
        {
            QAction action = (QAction) QSignalEmitter.signalSender();
            QByteArray fileFormat = QVariant.toByteArray(action.data());
            saveFile(new String(fileFormat.toByteArray()));
        }

        private void penColor()
        {
            QColor newColor = QColorDialog.getColor(scribbleArea.penColor());
            if (newColor.isValid())
                scribbleArea.setPenColor(newColor);
        }

        private void penWidth()
        {

            Integer newWidth = QInputDialog.getInteger(this, tr("Scribble"),
                                                tr("Select pen width:"),
                                                scribbleArea.penWidth(),
                                                1, 50, 1);
            if (newWidth != null)
                scribbleArea.setPenWidth(newWidth.intValue());
        }

        private boolean maybeSave()
        {
            if (scribbleArea.isModified()) {
               QMessageBox.StandardButton ret;
               ret = QMessageBox.warning(this, tr("Scribble"),
                                  tr("The image has been modified.\n" +
                                     "Do you want to save your changes?"),
                                  new QMessageBox.StandardButtons(QMessageBox.StandardButton.Save, QMessageBox.StandardButton.Discard));

                if (ret == QMessageBox.StandardButton.Save) {
                    return saveFile("png");
                } else if (ret == QMessageBox.StandardButton.Cancel) {
                    return false;
                }
            }
            return true;
        }

        private boolean saveFile(String fileFormat)
        {
            String initialPath = QDir.currentPath() + "/untitled." + fileFormat;

            String fileName = QFileDialog.getSaveFileName(this, tr("Save As"),
                                        initialPath,
                                        new QFileDialog.Filter(fileFormat.toUpperCase() + " Files (*."+
                                        fileFormat + ");;All Files (*)"));
            if (fileName.length() == 0) {
                return false;
            } else {
                return scribbleArea.saveImage(fileName, fileFormat);
            }
        }

        private void about()
        {
            QMessageBox.about(this, tr("About Scribble"),
                tr("<p>The <b>Scribble</b> example shows how to use QMainWindow as the "
                   +"base widget for an application, and how to reimplement some of "
                   +"QWidget's event handlers to receive the events generated for "
                   +"the application's widgets:</p><p> We reimplement the mouse event "
                   +"handlers to facilitate drawing, the paint event handler to "
                   +"update the application and the resize event handler to optimize "
                   +"the application's appearance. In addition we reimplement the "
                   +"close event handler to intercept the close events before "
                   +"terminating the application.</p><p> The example also demonstrates "
                   +"how to use QPainter to draw an image in real time, as well as "
                   +"to repaint widgets.</p>"));
        }

        private void createActions()
        {
            openAct = new QAction(tr("&Open..."), this);
            openAct.setShortcut(tr("Ctrl+O"));
            openAct.triggered.connect(this, "open()");

            saveAsActs = new LinkedList<QAction>();
            for (QByteArray format : QImageWriter.supportedImageFormats()) {
                String text = new String(format.toByteArray()).toUpperCase() + "...";

                QAction action = new QAction(text, this);
                action.setData(format);
                action.triggered.connect(this, "save()");
                saveAsActs.add(action);
            }

            printAct = new QAction(tr("&Print..."), this);
            printAct.triggered.connect(scribbleArea, "print()");

            exitAct = new QAction(tr("E&xit"), this);
            exitAct.setShortcut(tr("Ctrl+Q"));
            exitAct.triggered.connect(this, "close()");

            penColorAct = new QAction(tr("&Pen Color..."), this);
            penColorAct.triggered.connect(this, "penColor()");

            penWidthAct = new QAction(tr("Pen &Width..."), this);
            penWidthAct.triggered.connect(this, "penWidth()");

            clearScreenAct = new QAction(tr("&Clear Screen"), this);
            clearScreenAct.setShortcut(tr("Ctrl+L"));
            clearScreenAct.triggered.connect(scribbleArea, "clearImage()");

            aboutAct = new QAction(tr("&About"), this);
            aboutAct.triggered.connect(this, "about()");

            aboutQtAct = new QAction(tr("About &Qt"), this);
            aboutQtAct.triggered.connect(QApplication.instance(), "aboutQt()");
        }

        private void createMenus()
        {
            saveAsMenu = new QMenu(tr("&Save As"), this);
            for (QAction action : saveAsActs)
                saveAsMenu.addAction(action);

            fileMenu = new QMenu(tr("&File"), this);
            fileMenu.addAction(openAct);
            fileMenu.addMenu(saveAsMenu);
            fileMenu.addAction(printAct);
            fileMenu.addSeparator();
            fileMenu.addAction(exitAct);

            optionMenu = new QMenu(tr("&Options"), this);
            optionMenu.addAction(penColorAct);
            optionMenu.addAction(penWidthAct);
            optionMenu.addSeparator();
            optionMenu.addAction(clearScreenAct);

            helpMenu = new QMenu(tr("&Help"), this);
            helpMenu.addAction(aboutAct);
            helpMenu.addAction(aboutQtAct);

            menuBar().addMenu(fileMenu);
            menuBar().addMenu(optionMenu);
            menuBar().addMenu(helpMenu);
        }

        class ScribbleArea extends QWidget
        {
            private boolean modified;
            private boolean scribbling;
            private int myPenWidth;
            private QColor myPenColor;
            private QImage image;
            private QPoint lastPoint;

            public ScribbleArea()
            {
                image = new QImage();
                lastPoint = new QPoint();

                setAttribute(Qt.WidgetAttribute.WA_StaticContents);
                modified = false;
                scribbling = false;
                myPenWidth = 1;
                myPenColor = new QColor(Qt.GlobalColor.blue);
            }

            public boolean isModified()
            {
                return modified;
            }

            public QColor penColor()
            {
                return myPenColor;
            }

            public int penWidth()
            {
                return myPenWidth;
            }

            public boolean openImage(String fileName)
            {
                QImage loadedImage = new QImage();
                if (!loadedImage.load(fileName))
                    return false;

                QSize newSize = loadedImage.size().expandedTo(size());
                loadedImage = resizeImage(loadedImage, newSize);
                image = loadedImage;
                modified = false;
                update();
                return true;
            }

            public boolean saveImage(String fileName, String fileFormat)
            {
                QImage visibleImage = image;
                visibleImage = resizeImage(visibleImage, size());

                if (visibleImage.save(fileName, fileFormat)) {
                    modified = false;
                    return true;
                } else {
                    return false;
                }
            }

            public void setPenColor(QColor newColor)
            {
                myPenColor = newColor;

            }

            public void setPenWidth(int newWidth)
            {
                myPenWidth = newWidth;
            }

            public void clearImage()
            {
                image.fill(new QColor(Qt.GlobalColor.white).rgb());
                modified = true;
                update();
            }

            @Override
            protected void mousePressEvent(QMouseEvent event)
            {
                if (event.button() == Qt.MouseButton.LeftButton) {
                    lastPoint = event.pos();
                    scribbling = true;
                }
            }

            @Override
            protected void mouseMoveEvent(QMouseEvent event)
            {
                if ((event.buttons().isSet(Qt.MouseButton.LeftButton)) && scribbling)
                    drawLineTo(event.pos());
            }

            @Override
            protected void mouseReleaseEvent(QMouseEvent event)
            {
                if (event.button() == Qt.MouseButton.LeftButton && scribbling) {
                    drawLineTo(event.pos());
                    scribbling = false;
                }
            }

            @Override
            protected void paintEvent(QPaintEvent event)
            {
                QPainter painter = new QPainter(this);
                painter.save();
                painter.drawImage(new QPoint(0, 0), image);
                painter.restore();
            }

            @Override
            protected void resizeEvent(QResizeEvent event)
            {
                if (width() > image.width() || height() > image.height()) {
                    int newWidth = Math.max(width() + 128, image.width());
                    int newHeight = Math.max(height() + 128, image.height());
                    image = resizeImage(image, new QSize(newWidth, newHeight));
                    update();
                }
                super.resizeEvent(event);
            }

            private void drawLineTo(QPoint endPoint)
            {
                QPainter painter = new QPainter(image);
                painter.setPen(new QPen(myPenColor, myPenWidth, Qt.PenStyle.SolidLine, Qt.PenCapStyle.RoundCap,
                                    Qt.PenJoinStyle.RoundJoin));
                painter.drawLine(lastPoint, endPoint);
                modified = true;

                int rad = (myPenWidth / 2) + 2;
                update(new QRect(lastPoint, endPoint).normalized()
                                                 .adjusted(-rad, -rad, +rad, +rad));
                lastPoint = endPoint;

                painter.end();
            }

            public QImage resizeImage(QImage image, QSize newSize)
            {
                if (image.size() == newSize)
                    return image;

                QImage newImage = new QImage(newSize, QImage.Format.Format_RGB32);
                newImage.fill(new QColor(Qt.GlobalColor.white).rgb());
                QPainter painter = new QPainter(newImage);
                painter.drawImage(new QPoint(0, 0), image);
                painter.end();

                return newImage;
            }

            public void print()
            {
                QPrinter printer = new QPrinter(QPrinter.PrinterMode.HighResolution);

                QPrintDialog printDialog = new QPrintDialog(printer, this);
                if (printDialog.exec() == QDialog.DialogCode.Accepted.value()) {
                    QPainter painter = new QPainter(printer);
                    QRect rect = painter.viewport();
                    QSize size = image.size();
                    size.scale(rect.size(), Qt.AspectRatioMode.KeepAspectRatio);
                    painter.setViewport(rect.x(), rect.y(), size.width(), size.height());
                    painter.setWindow(image.rect());
                    painter.drawImage(0, 0, image);
                    painter.end();
                }
            }
        }

        public static void main(String args[])
        {
            QApplication.initialize(args);

            new Scribble().show();

            QApplication.exec();
        }
    }