gann-cdf / graphics

import javax.swing.*;

import java.awt.*;

/**

 * <p>Extendable window controller for {@link DrawingPanel} objects</p>

 *

 * <p>Extend this class to create your own drawings. Override the abstract method {@link #setup()} to make your drawing

 * instructions. The recommended approach is to create a new Java class file and to type exactly this (replacing

 * {@code MyDrawingApp} with your preferred name, of course):</p>

 *

 * <pre>

 *   public class MyDrawingApp extends AppWindow {}

 * </pre>

 *

 * <p>This will generate a number of errors in your IDE. Go ahead and let the IDE fix them automagically. The IDE will

 * import the AppWindow class, and then create a method stub for {@code setup()}, resulting in something like this:</p>

 *

 * <pre>

 *   import org.gannacademy.cdf.graphics.ui.*;

 *

 *   public class MyDrawingApp extends AppWindow {

 *     @Override

 *     public void setup() {

 *

 *     }

 *   }

 * </pre>

 *

 * <p>Instantiate a {@code MyDrawingApp} object to create a window containing your drawing.</p>

 *

 * <p>Additional overrideable methods include {@link #loop()} and {@link #done()}. {@code loop()} will be

 * called repeatedly (inside a loop!) while {@code done()} returns {@code false} — when {@code done()} returns

 * {@code true}, the control loop ends (although the application will continue running until the window is closed).</p>

 *

 * @author <a href="https://github.com/gann-cdf/graphics/issues" target="_blank">Seth Battis</a>

 */

public abstract class AppWindow extends JFrame {

    public static final String DEFAULT_TITLE = "Gann Graphics App";

    public static final boolean DEFAULT_FULLSCREEN = false;

    public static final long DEFAULT_REPAINT_DELAY = 10;

    private DrawingPanel drawingPanel;

    /**

     * Construct a new {@link DrawingPanel} in a window with the default title

     */

    public AppWindow() {

        this(DEFAULT_TITLE, DEFAULT_FULLSCREEN, DEFAULT_REPAINT_DELAY);

    }

    /**

     * Construct a new {@link DrawingPanel} in a window with a custom name

     *

     * @param title The title of the window (shown in the draggable titlebar)

     */

    public AppWindow(String title) {

        this(title, DEFAULT_FULLSCREEN, DEFAULT_REPAINT_DELAY);

    }

    public AppWindow(String title, boolean isFullScreen) {

        this(title, isFullScreen, DEFAULT_REPAINT_DELAY);

    }

    /**

     * <p>Construct a new {@link DrawingPanel} in a window</p>

     *

     * <p>Full screen windows default to the main display.</p>

     *

     * @param title        for the window

     * @param isFullScreen whether or not the window is framed or full screen

     */

    public AppWindow(String title, boolean isFullScreen, long repaintDelay) {

        super(title);

        AppWindow self = this;

        SwingUtilities.invokeLater(new Runnable() {

            @Override

            public void run() {

                setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

                drawingPanel = new DrawingPanel();

                add(drawingPanel);

                if (isFullScreen) {

                    setExtendedState(JFrame.MAXIMIZED_BOTH);

                    setUndecorated(true);

                    DisplayMode display = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices()[0].getDisplayMode();

                    setSize(display.getWidth(), display.getHeight());

                }

                pack();

                setup();

                setLocationRelativeTo(null);

                setVisible(true);

                (new Repainter(self, repaintDelay)).execute();

                (new Animator(self)).execute();

            }

        });

    }

    private void repaintOnEDT() {

        SwingUtilities.invokeLater(new Runnable() {

            @Override

            public void run() {

                repaint();

            }

        });

    }

    private static class Animator extends SwingWorker<Void,Void> {

        AppWindow window;

        Animator(AppWindow window) {

            this.window = window;

        }

        @Override

        protected Void doInBackground() throws Exception {

            while(!window.done()) {

                window.loop();

                window.repaintOnEDT();

            }

            return null;

        }

    }

    private static class Repainter extends SwingWorker<Void,Void> {

        AppWindow window;

        long delay;

        Repainter(AppWindow window, long delay) {

            this.window = window;

            this.delay = Math.max(1, delay);

        }

        @Override

        protected Void doInBackground() throws Exception {

            //noinspection InfiniteLoopStatement

                window.repaintOnEDT();

                //noinspection BusyWait

                Thread.sleep(delay);

            }

        }

    }

    /**

     * Set the size of the window

     *

     * @param width  in pixels

     * @param height in pixels

     */

    /**

     * Pause the control loop

     *

     * @param delay in milliseconds

     */

    protected void sleep(long delay) {

        try {

            Thread.sleep(delay);

        }

    }

    /**

     * <p>Override this method to define your drawing</p>

     *

     * <p>This method is called before the window is made visible. All drawing components that need to be rendered at the

     * start of the program run should be defined in this method.</p>

     */

    protected abstract void setup();

    /**

     * <p>Override this method to update drawings in the control loop</p>

     *

     * <p>This method represents a <i>single</i> iteration of the control loop. Care should be taken to avoid writing

     * blocking code in this method (e.g. {@code for} loops designed to animate a single object) — rather, drawing

     * components should be adjusted based on the values of instance variables, whose values are changed incrementally

     * in each call to this method. For example:</p>

     *

     * <pre>

     *   private double x, y;

     *   private Rectangle r;

     *

     *   // setup() and other methods…

     *

     *   @Override

     *   public void loop() {

     *     x += 1;

     *     y = 20 * Math.sin(x * 20);

     *     r.moveTo(x, y);

     *   }

     * </pre>

     *

     * <p>The above code animates a rectangle moving elegantly in a sine wave (scaled up 20&times;)across the window.</p>

     */

    protected void loop() {

    }

    /**

     * <p>Override this method to set the condition that ends the control loop</p>

     *

     * <p>By default, this method will always return {@code false}, so that the control loop runs indefinitely.</p>

     *

     * @return {@code true} if the control loop should end, {@code false} otherwise

     */

    protected boolean done() {

        return false;

    }

    /**

     * <p>Access the {@link DrawingPanel} object contained in this window</p>

     *

     * <p>All drawing instructions require a drawing panel on which to execute them. This is the default drawing panel.</p>

     *

     * @return The drawing panel in this window

     */

    public DrawingPanel getDrawingPanel() {

        return drawingPanel;

    }

}