Killer Game Programming in Java

The Sounds Panel

SoundsPanel implements a JPanel that draws a white background and four images. The interesting part of the code is the setting up and use of the images' hot spots (rectangular areas the same size as each image). If a mouse press is inside one of the hot spots, then LoadersTests' playClip() plays the associated clip.

The SoundsPanel constructor stores a reference to LoadersTests, calls initImages(), and sets up the MouseListener to call selectImage():

    // globals
    private static final int PWIDTH = 350;     // size of this panel
    private static final int PHEIGHT = 350;

    private LoadersTests topLevel;


    public SoundsPanel(LoadersTests sts)
    { topLevel = sts;
      setPreferredSize( new Dimension(PWIDTH, PHEIGHT) );
      initImages();
      addMouseListener( new MouseAdapter() {
        public void mousePressed( MouseEvent e)
        { selectImage( e.getX(), e.getY());  }
      } );
    }

initImages() uses ImagesLoader to load the four GIFs, whose names are hard-wired into the code in the names[] array. The width and height of each image is used to build the array of Rectangle objects that represent the hot spots:

 // globals // clip image names private final static String[] names = {"dog", "cat", "sheep", "chicken"}; // on-screen top-left coords for the images private final static int[] xCoords = {20, 210, 20, 210}; private final static int[] yCoords = {25, 25, 170, 170}; // location of image and sound info private final static String IMS_FILE = "imagesInfo.txt"; private int numImages; private BufferedImage[] images; private ...