snow.java

书籍"Java_面向事件编程"的附带光盘代码

import objectdraw.*;
import java.awt.*;

// Program which creates clouds which create snow, sleet, and tomatoes
// when the user clicks
public class Snow extends WindowController {
    
    // dimensions and location of the screen
    private static final int SCREEN_LEFT = 0;
    private static final int SCREEN_TOP = 0;
    private static final int SCREEN_HEIGHT = 400;
    private static final int SCREEN_WIDTH = 500;
    
    // constants for the moon size and location
    private static final int MOON_INSET = 50;
    private static final int MOON_SIZE = 70;
    
    // sizes and locations for the bricks
    private static final double BRICK_LINE = SCREEN_HEIGHT*0.85;
    private static final double BRICK_HEIGHT = SCREEN_HEIGHT*.04;
    private static final double SKYLINE = BRICK_LINE + BRICK_HEIGHT;
    private static final double BRICK_WIDTH = 30;
    private static final double BRICK_SPACING = 3;
    
    // colors of the sky, mortar, and brick
    private final Color NIGHTSKY = new Color(50, 50, 100);
    private final Color MORTAR = new Color(200, 200, 200);
    private final Color BRICKRED = new Color(150, 40, 40);
    
    // image of the snow
    private Image snowPic;
    
    public void begin() {
        
        // where to draw next brick
        double brickPosition;  
        
        // get snow picture
        snowPic = getImage("snow.gif");
        
        // draw solid sky, mortar, and moon
        new FilledRect(0,0,SCREEN_WIDTH,SKYLINE,
                       canvas).setColor(NIGHTSKY);
        new FilledRect(0,SKYLINE,
                       SCREEN_WIDTH,SCREEN_HEIGHT-BRICK_LINE,
                       canvas).setColor(MORTAR);
        new FilledOval(MOON_INSET,MOON_INSET,MOON_SIZE,MOON_SIZE,
                       canvas).setColor(Color.white);
        
        // add the bricks
        brickPosition = 0;
        while ( brickPosition < SCREEN_WIDTH ) {
            new FilledRect(brickPosition, BRICK_LINE,
                           BRICK_WIDTH, BRICK_HEIGHT,
                           canvas).setColor(BRICKRED);
            
            brickPosition = brickPosition + BRICK_WIDTH + BRICK_SPACING;
        }
    }
    
    public void onMouseClick(Location point) {
        // make a new cloud when the user clicks
        new Cloud(snowPic, SCREEN_WIDTH, SCREEN_HEIGHT, canvas);
    }
}