plane.java

《j2me开发精解〉（詹健飞）CD-rom附带源码。用netbeans

package com.j2medev.chapter5.example.hold;

import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.Sprite;

import com.j2medev.chapter5.utility.ImageUtilities;

public class Plane extends Sprite {
    final static public int STATE_NORMAL = 1;// 正常状态
    
    final static public int STATE_REST = 2;// 无敌状态
    
    final static public int STATE_EXPLOSION = 3;// 爆炸状态
    
    final static public int STATE_DEAD = 4;// 爆炸状态
    
    public int state = 0;// 状态变量
    
    public int bombnum;
    
    public Sprite rest;// 无敌效果
    
    public Sprite explosion;
    
    public GameWorld world;
    
    protected Plane(Image img, int w, int h) {
        super(img, w, h);
    }
    
    public void update() {
        switch (state) {// 根据状态，更新逻辑和画面
            case STATE_NORMAL:
                input();// 处理输入
                setVisible(true);
                rest.setVisible(false);
                explosion.setVisible(false);
                break;
            case STATE_REST:
                input();// 处理输入
                rest.setVisible(true);
                rest.nextFrame();
                rest.setRefPixelPosition(this.getRefPixelX(), this.getRefPixelY());
                world.bullets.killbullets(this, 28);
                if (rest.getFrame() == rest.getFrameSequenceLength() - 1) {
                    state = STATE_NORMAL;
                }
                break;
            case STATE_EXPLOSION:
                input();// 处理输入
                explosion.setVisible(true);
                explosion.nextFrame();
                explosion.setRefPixelPosition(this.getRefPixelX(), this
                        .getRefPixelY());
                if (explosion.getFrame() == explosion.getFrameSequenceLength() - 1) {
                    state = STATE_DEAD;
                }
                break;
            case STATE_DEAD:
                explosion.setVisible(false);
                rest.setVisible(false);
                setVisible(false);
                break;
        }
    }
    
    public void reset() {
        state = STATE_NORMAL;
        setFrame(0);
        setPosition(world.width / 2, world.height / 2);
        defineReferencePixel(getWidth() / 2, getHeight() / 2);
        rest.setFrame(rest.getFrameSequenceLength() - 1);
        rest.setVisible(false);
        rest.defineReferencePixel(rest.getWidth() / 2, rest.getHeight() / 2);
        explosion.setFrame(explosion.getFrameSequenceLength() - 1);
        explosion.setVisible(false);
        explosion.defineReferencePixel(explosion.getWidth() / 2, explosion
                .getHeight() / 2);
        bombnum = 3;
    }
    
    public void collides() {
        state = STATE_EXPLOSION;
    }
    
    public static Plane createPlane(GameWorld world) {
        Image img = ImageUtilities.createImage(("/plane.png"));
        Plane p = new Plane(img, 40, 40);
        p.world = world;
        img = ImageUtilities.createImage(("/rest.png"));
        Sprite s = new Sprite(img, 65, 65);
        p.rest = s;
        img = ImageUtilities.createImage(("/explosion.png"));
        s = new Sprite(img, 71, 100);
        p.explosion = s;
        p.reset();
        return p;
    }
    
    public void input() {
        boolean hasInput = false;
        if (world.upAction.isPressed()) {
            hasInput = true;
            if (getY() - 3 >= 0)
                move(0, -3);
            setFrame(0);
            setTransform(Sprite.TRANS_NONE);
        }
        if (world.downAction.isPressed()) {
            hasInput = true;
            if (getY() + getHeight() + 3 < world.viewport_height)
                move(0, 3);
            setFrame(0);
            setTransform(Sprite.TRANS_NONE);
        }
        if (world.leftAction.isPressed()) {
            hasInput = true;
            if (getX() - 3 >= 0)
                move(-3, 0);
            setFrame(1);
            setTransform(Sprite.TRANS_NONE);
        }
        if (world.rightAction.isPressed()) {
            hasInput = true;
            if (getX() + getWidth() + 3 < world.viewport_width)
                move(3, 0);
            setFrame(1);
            setTransform(Sprite.TRANS_MIRROR);
        }
        if (world.fireAction.isPressed()) {
            hasInput = true;
            if (state == STATE_NORMAL && bombnum > 0) {
                state = STATE_REST;
                bombnum--;
            }
            System.out.println("fire");
        }
        if (!hasInput) {
            setFrame(0);
            setTransform(Sprite.TRANS_NONE);
        }
    }
    
}