package edu.umd.cs.piccolox;

import javax.swing.JApplet;
import javax.swing.SwingUtilities;

import edu.umd.cs.piccolo.PCanvas;

/**
 * <b>PApplet</b> is meant to be subclassed by applications that just need a
 * PCanvas embedded in a web page.
 * 
 * @version 1.0
 * @author Jesse Grosjean
 */
public class PApplet extends JApplet {

    private PCanvas canvas;

    public void init() {
        setBackground(null);

        canvas = createCanvas();
        getContentPane().add(canvas);
        validate();
        canvas.requestFocus();
        beforeInitialize();

        // Manipulation of Piccolo's scene graph should be done from Swings
        // event dispatch thread since Piccolo is not thread safe. This code
        // calls initialize() from that thread once the PFrame is initialized,
        // so you are safe to start working with Piccolo in the initialize()
        // method.
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                PApplet.this.initialize();
                repaint();
            }
        });
    }

    public PCanvas getCanvas() {
        return canvas;
    }

    public PCanvas createCanvas() {
        return new PCanvas();
    }

    // ****************************************************************
    // Initialize
    // ****************************************************************

    /**
     * This method will be called before the initialize() method and will be
     * called on the thread that is constructing this object.
     */
    public void beforeInitialize() {
    }

    /**
     * Subclasses should override this method and add their Piccolo
     * initialization code there. This method will be called on the swing event
     * dispatch thread. Note that the constructors of PFrame subclasses may not
     * be complete when this method is called. If you need to initailize some
     * things in your class before this method is called place that code in
     * beforeInitialize();
     */
    public void initialize() {
    }
}