GameView.java

package vooga.scroller.view;

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import java.util.Collection;
import java.util.Collections;
import java.util.Set;
import java.util.TreeSet;
import javax.swing.JComponent;
import javax.swing.Timer;
import vooga.scroller.scrollingmanager.ScrollingManager;
import vooga.scroller.util.Renderable;
import vooga.scroller.util.Renderer;
import vooga.scroller.util.mvc.Gaming;
import vooga.scroller.model.Model;


/**
 *
 * @author Ross Cahoon
 */
public class GameView extends JComponent implements Renderer<Gaming>{
    // default serialization ID
    private static final long serialVersionUID = 1L;
    // animate 25 times per second if possible
    public static final int FRAMES_PER_SECOND = 25;
    // better way to think about timed events (in milliseconds)
    public static final int ONE_SECOND = 1000;
    public static final int DEFAULT_DELAY = ONE_SECOND / FRAMES_PER_SECOND;
    // input state
    public static final int NO_KEY_PRESSED = -1;

    // drives the animation
    private Timer myTimer;
    // game to be animated
    private Model myGame;
    // input state
    private int myLastKeyPressed;
    private Point myLastMousePosition;
    // MULTIPLE KEY SUPPORT
    private Set<Integer> myKeys;
    private ScrollingManager myScrollManager;


    /**
     * Create a panel so that it knows its size
     */
    public GameView (Dimension size, ScrollingManager sm) {
        // set size (a bit of a pain)
        setPreferredSize(size);
        setSize(size);
        // prepare to receive input
        setFocusable(true);
        requestFocus();
        setInputListeners();
        setScrollManager(sm);
    }

    private void setScrollManager (ScrollingManager sm) {
        myScrollManager = sm;
        myScrollManager.initView(this);
        
    }

    /**
     * Paint the contents of the canvas.
     * 
     * Never called by you directly, instead called by Java runtime
     * when area of screen covered by this container needs to be
     * displayed (i.e., creation, uncovering, change in status)
     * 
     * @param pen used to paint shape on the screen
     */
    @Override
    public void paintComponent (Graphics pen) {

        // first time needs to be special cased :(
        if (myGame != null && myScrollManager != null) {
               myScrollManager.viewPaint(pen);
        }      
    }

    /**
     * Returns last key pressed by the user or -1 if nothing is pressed.
     */
    public int getLastKeyPressed () {
        return myLastKeyPressed;
    }

    /**
     * Returns all keys currently pressed by the user.
     */
    // MULTIPLE KEY SUPPORT
    public Collection<Integer> getKeysPressed () {
        return Collections.unmodifiableSet(myKeys);
    }

    /**
     * Returns last position of the mouse in the canvas.
     */
    public Point getLastMousePosition () {
        return myLastMousePosition;
    }

    /**
     * Start the animation.
     */
    public void start () {
        final int stepTime = DEFAULT_DELAY;
        // create a timer to animate the canvas
        Timer timer = new Timer(stepTime, 
                                new ActionListener() {
            public void actionPerformed (ActionEvent e) {
                myGame.update((double) stepTime / ONE_SECOND);
                repaint();
            }
        });
        // start animation
        myScrollManager.initModel(myGame);
        timer.start();
    }
    
    public void setModel (Model m) {
        myGame = m;
    }

    /**
     * Stop the animation.
     */
    public void stop () {
        myTimer.stop();
    }

    /**
     * Create listeners that will update state based on user input.
     */
    private void setInputListeners () {
        // initialize input state
        myLastKeyPressed = NO_KEY_PRESSED;
        // MULTIPLE KEY SUPPORT
        myKeys = new TreeSet<Integer>();
        addKeyListener(new KeyAdapter() {
            @Override
            public void keyPressed (KeyEvent e) {
                myLastKeyPressed = e.getKeyCode();
                // MULTIPLE KEY SUPPORT
                myKeys.add(e.getKeyCode());
            }
            @Override
            public void keyReleased (KeyEvent e) {
                myLastKeyPressed = NO_KEY_PRESSED;
                // MULTIPLE KEY SUPPORT
                myKeys.remove((Integer)e.getKeyCode());
            }
        });
        myLastMousePosition = new Point();
        addMouseMotionListener(new MouseMotionAdapter() {
            @Override
            public void mouseMoved (MouseEvent e) {
                myLastMousePosition = e.getPoint();
            }
        });
    }

    @Override
    public void render (Renderable<Gaming> renderable) {
        setModel((Model) renderable);
    }


    @Override
    public Renderable<Gaming> getRenderable () {
        return myGame;
    }

    @Override
    public void setRenderable (Renderable<Gaming> renderable) {
        setModel((Model) renderable);        
    }

}