jfreechart example source code file (SWTStrokeCanvas.java)

This example jfreechart source code file (SWTStrokeCanvas.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jfreechart tags/keywords

awt, basic, basicstroke, basicstroke, can, canvas, image, paintlistener, rectangle, runtimeexception, stroke, swtstrokecanvas, swtstrokecanvas, transform, transform

The jfreechart SWTStrokeCanvas.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2006, by Object Refinery Limited and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * This library is free software; you can redistribute it and/or modify it 
 * under the terms of the GNU Lesser General Public License as published by 
 * the Free Software Foundation; either version 2.1 of the License, or 
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
 * USA.  
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
 * in the United States and other countries.]
 *
 * --------------------
 * SWTStrokeCanvas.java
 * --------------------
 * (C) Copyright 2006, by Henry Proudhon and Contributors.
 *
 * Original Author:  Henry Proudhon (henry.proudhon AT ensmp.fr);
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * Changes
 * -------
 * 01-Aug-2006 : New class (HP);
 * 
 */

package org.jfree.experimental.chart.swt.editor;

import java.awt.BasicStroke;
import java.awt.Stroke;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.graphics.Transform;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;

/**
 * A control for displaying a <code>Stroke sample.
 */
class SWTStrokeCanvas extends Canvas {
    
    /**
     * Creates a new instance.
     * 
     * @param parent  the parent.
     * @param style  the style.
     * @param image  the image.
     */
    public SWTStrokeCanvas(Composite parent, int style, Image image) {
        this(parent, style);
    }

    /**
     * Creates a new instance.
     * 
     * @param parent  the parent.
     * @param style  the style.
     */
    public SWTStrokeCanvas(Composite parent, int style) {
        super(parent, style);
        addPaintListener(new PaintListener() {
            public void paintControl(PaintEvent e) {
                BasicStroke stroke = (BasicStroke) getStroke();
                if (stroke != null) {
                    int x, y;
                    Rectangle rect = getClientArea();
                    x = (rect.width - 100) / 2;
                    y = (rect.height - 16) / 2;
                    Transform swtTransform = new Transform(e.gc.getDevice()); 
                    e.gc.getTransform(swtTransform);
                    swtTransform.translate(x, y);
                    e.gc.setTransform(swtTransform);
                    swtTransform.dispose();
                    e.gc.setBackground(getDisplay().getSystemColor(
                            SWT.COLOR_BLACK));
                    e.gc.setLineWidth((int) stroke.getLineWidth());
                    e.gc.drawLine(10, 8, 90, 8);
                }
            }
        });
    }
    
    /**
     * Sets the stroke.
     * 
     * @param stroke  the stroke.
     */
    public void setStroke(Stroke stroke) {
        if (stroke instanceof BasicStroke) {
            setData(stroke);
        }
        else { 
            throw new RuntimeException(
                "Can only handle 'Basic Stroke' at present.");
        }
    }

    /**
     * Returns the stroke.
     * 
     * @return The stroke.
     */
    public BasicStroke getStroke() {
        return (BasicStroke) this.getData();
    }
}