HTMLNode is a Piccolo node for rendering HTML text.

HTMLNode.java

/* Copyright 2005, University of Colorado */

/*
 * CVS Info -
 * Filename : $Source$
 * Branch : $Name$
 * Modified by : $Author$
 * Revision : $Revision$
 * Date modified : $Date$
 */

package edu.colorado.phet.common.piccolophet.nodes;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Rectangle;

import javax.swing.JLabel;
import javax.swing.plaf.basic.BasicHTML;
import javax.swing.text.View;

import edu.umd.cs.piccolo.PNode;
import edu.umd.cs.piccolo.util.PPaintContext;

/**
 * HTMLNode is a Piccolo node for rendering HTML text.
 *
 * @author Chris Malley (cmalley@pixelzoom.com)
 * @author Sam Reid
 * @author seanh
 * @version $Revision$
 */
public class HTMLNode extends PNode {

    //----------------------------------------------------------------------------
    // Class data
    //----------------------------------------------------------------------------
    private static final Font DEFAULT_FONT = new JLabel().getFont();
    private static final Color DEFAULT_HTML_COLOR = Color.BLACK;    //----------------------------------------------------------------------------
    // Instance data
    //----------------------------------------------------------------------------
    private String html;
    private Font font;
    private Color htmlColor;
    private JLabel htmlLabel;
    private View htmlView;
    private final Rectangle htmlBounds; // BasicHTML$Renderer.paint requires a Rectangle

    //----------------------------------------------------------------------------
    // Constructors
    //----------------------------------------------------------------------------
    public HTMLNode() {
        this(null, DEFAULT_FONT, DEFAULT_HTML_COLOR);
    }

    public HTMLNode(String html) {
        this(html, DEFAULT_FONT, DEFAULT_HTML_COLOR);
    }

    public HTMLNode(String html, Color htmlColor) {
        this(html, DEFAULT_FONT, htmlColor);
    }

    public HTMLNode(String html, Font font, Color htmlColor) {
        this.html = html;
        this.font = font;
        this.htmlColor = htmlColor;
        htmlLabel = new JLabel();
        htmlBounds = new Rectangle();
        update();
    }
    
    //----------------------------------------------------------------------------
    // Accessors
    //----------------------------------------------------------------------------
    /**
     * Gets the HTML string.
     *
     * @return HTML string
     */
    public String getHTML() {
        return html;
    }

    /**
     * Sets the HMTL string.
     *
     * @param html
     */
    public void setHTML(String html) {
        if ((this.html != null && html == null) || (this.html == null && html != null) || (!this.html.equals(html))) {
            this.html = html;
            update();
        }
    }

    /**
     * Gets the font.
     *
     * @return the font
     */
    public Font getFont() {
        return font;
    }

    /**
     * Sets the font.
     *
     * @param font
     */
    public void setFont(Font font) {
        this.font = font;
        update();
    }

    /**
     * Gets the color used to render the HTML.
     * If you want to get the paint used for the node, use getPaint.
     *
     * @return the color used to render the HTML.
     */
    public Color getHTMLColor() {
        return htmlColor;
    }

    /**
     * Sets the color used to render the HTML.
     * If you want to set the paint used for the node, use setPaint.
     *
     * @param color
     */
    public void setHTMLColor(Color color) {
        htmlColor = color;
        update();
    }

    //----------------------------------------------------------------------------
    // Update handler
    //----------------------------------------------------------------------------

    /*
     * Updates everything that is involved in rendering the HTML string.
     * This method is called when one the HTML-related properties is modified.
     */
    private void update() {
        htmlLabel.setText(html);
        htmlLabel.setFont(font);
        htmlLabel.setForeground(htmlColor);
        htmlLabel.setSize(htmlLabel.getPreferredSize());
        htmlView = BasicHTML.createHTMLView(htmlLabel, html == null ? "" : html);
        htmlBounds.setRect(0, 0, getBounds().getWidth(), getBounds().getHeight());
        repaint();
    }
    
    //----------------------------------------------------------------------------
    // PNode overrides
    //----------------------------------------------------------------------------

    @Override
    public boolean setBounds(double x, double y, double width, double height) {
        boolean boundsChanged = super.setBounds(x,y,width,height);
        update();
        return boundsChanged;
    }
    
    @Override
    public boolean setBounds(java.awt.geom.Rectangle2D newBounds) {
        boolean boundsChanged = super.setBounds(newBounds);
        update();
        return boundsChanged;
    }
    
    /*
     * Paints the node.
     * The HTML string is painted last, so it appears on top of any child nodes.
     * 
     * @param paintContext
     */
    @Override
    protected void paint(PPaintContext paintContext) {
        super.paint(paintContext);
        if (htmlLabel.getWidth() == 0 || htmlLabel.getHeight() == 0) {
            return;
        }
        Graphics2D g2 = paintContext.getGraphics();
        htmlView.paint(g2, htmlBounds);
    }
}