SimplePaint.java

/**

 * 

 */

package test;

import java.awt.BorderLayout;

import java.awt.Color;

import java.awt.Component;

import java.awt.Dimension;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.Point;

import java.awt.RenderingHints;

import java.awt.Shape;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.MouseAdapter;

import java.awt.event.MouseEvent;

import java.awt.geom.Line2D;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import javax.swing.JButton;

import javax.swing.JColorChooser;

import javax.swing.JComponent;

import javax.swing.JFrame;

import javax.swing.JLabel;

import javax.swing.JSpinner;

import javax.swing.JToggleButton;

import javax.swing.JToolBar;

import javax.swing.SpinnerNumberModel;

import javax.swing.event.ChangeEvent;

import javax.swing.event.ChangeListener;

/**

 * @author Christoph Läubrich

 */

public class SimplePaint extends JComponent {

    private static final long serialVersionUID = -268370314148601306L;

    /* (non-Javadoc)

     * @see javax.swing.JComponent#paintComponent(java.awt.Graphics)

     */

    @Override

    protected void paintComponent(Graphics g) {

        Graphics2D graphics = (Graphics2D) g.create();

        try {

            Dimension dimension = getSize();

            if (isOpaque()) {

                g.setColor(Color.WHITE);

                g.fillRect(0, 0, dimension.width, dimension.height);

            }

            drawCanvas(graphics, dimension);

        } finally {

            graphics.dispose();

        }

    }

    private final List<PaintObject> paintObjects = new ArrayList<SimplePaint.PaintObject>();

    private PaintObject             previewObject;

    /**

     * Zeichnet den Aktuellen Zustand auf das angegeben Grafikobjekt

     * 

     * @param g

     * @param dimension

     */

    public void drawCanvas(Graphics2D g, Dimension dimension) {

        //Anti alias off

        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF);

        g.scale(zoom, zoom);

        synchronized (paintObjects) {

            for (PaintObject object : paintObjects) {

                paintShape(g, object);

            }

        }

        if (previewObject != null) {

            paintShape(g, previewObject);

        }

    }

    protected void paintShape(Graphics2D g, PaintObject object) {

        g.setColor(object.getColor());

        g.draw(object.getShape());

    }

    public static class PaintObject {

        public PaintObject(Shape shape, Color color) {

            super();

            this.shape = shape;

            this.color = color;

        }

        private Shape shape;

        private Color color;

        public void setShape(Shape shape) {

            this.shape = shape;

        }

        public Shape getShape() {

            return shape;

        }

        public void setColor(Color color) {

            this.color = color;

        }

        public Color getColor() {

            return color;

        }

    }

    /**

     * @return the current value of paintObjects

     */

    public List<PaintObject> getPaintObjects() {

        synchronized (paintObjects) {

            return Collections.unmodifiableList(paintObjects);

        }

    }

    public void insertShape(PaintObject object) {

        synchronized (paintObjects) {

            paintObjects.add(object);

        }

    }

    public void setPreview(PaintObject object) {

        this.previewObject = object;

    }

    public void setZoomFactor(double zoom) {

        this.zoom = zoom;

    }

    public double getZoomFactor() {

        return this.zoom;

    }

    private static Color currentColor = Color.RED;

    private double       zoom         = 1.0;

    public static void main(String[] args) {

        SimplePaint paint = new SimplePaint();

        JFrame frame = new JFrame("Test");

        frame.add(getToolbar(paint), BorderLayout.NORTH);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.add(paint);

        frame.setLocationRelativeTo(null);

        frame.setSize(800, 600);

        frame.setVisible(true);

    }

    /**

     * @return

     */

    private static Component getToolbar(final SimplePaint paint) {

        final JToolBar toolBar = new JToolBar("my Toolbar");

        final JButton button = new JButton("Choose Color");

        final JLabel colorLabel = new JLabel("   ");

        colorLabel.setOpaque(true);

        colorLabel.setBackground(currentColor);

        button.addActionListener(new ActionListener() {

            @Override

            public void actionPerformed(ActionEvent e) {

                currentColor = JColorChooser.showDialog(toolBar, "Choose Color", currentColor);

                colorLabel.setBackground(currentColor);

            }

        });

        final JToggleButton drawLine = new JToggleButton("draw line");

        drawLine.addActionListener(new ActionListener() {

            @Override

            public void actionPerformed(ActionEvent e) {

                paint.setZoomFactor(1);

                paint.repaint();

            }

        });

        MouseAdapter lineMouse = new MouseAdapter() {

            private Point start;

            @Override

            public void mouseReleased(MouseEvent e) {

                if (drawLine.isSelected()) {

                    paint.insertShape(new PaintObject(new Line2D.Double(start, e.getPoint()), currentColor));

                    paint.setPreview(null);

                    paint.repaint();

                    start = null;

                }

            }

            @Override

            public void mousePressed(MouseEvent e) {

                if (drawLine.isSelected()) {

                    start = e.getPoint();

                }

            }

            /* (non-Javadoc)

             * @see java.awt.event.MouseAdapter#mouseDragged(java.awt.event.MouseEvent)

             */

            @Override

            public void mouseDragged(MouseEvent e) {

                if (drawLine.isSelected() && start != null) {

                    final Line2D.Double shape = new Line2D.Double(start, e.getPoint());

                    paint.setPreview(new PaintObject(shape, currentColor));

                    paint.repaint();

                }

            }

        };

        paint.addMouseListener(lineMouse);

        paint.addMouseMotionListener(lineMouse);

        final JSpinner spinner = new JSpinner(new SpinnerNumberModel(100, 10, 400, 10));

        spinner.addChangeListener(new ChangeListener() {

            @Override

            public void stateChanged(ChangeEvent e) {

                drawLine.setSelected(false);

                paint.setZoomFactor(((Number) spinner.getValue()).doubleValue() / 100.0);

                paint.repaint();

            }

        });

        toolBar.add(colorLabel);

        toolBar.addSeparator();

        toolBar.add(button);

        toolBar.add(drawLine);

        toolBar.addSeparator();

        toolBar.add(new JLabel("Zoom"));

        toolBar.add(spinner);

        toolBar.addSeparator();

        return toolBar;

    }

}