今天学习了下拉框实现与简单游戏的实现

package com.Cra2iTeT.snake;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.Random;

public class GamePanel extends JPanel implements KeyListener, ActionListener {
int length;//蛇的长度
int[] snakeX = new int[600];//蛇的x坐标
int[] snakeY = new int[500];//蛇的y坐标
String fx = "R";//R:右,L:左,U:上,D:下

boolean isStart = false;//游戏开始标志

Timer timer = new Timer(100, this);//定时器

int foodX;//食物的x坐标  
int foodY;//食物的y坐标  
Random random = new Random();

boolean isFail = false;//游戏失败标识

int score;//积分

//构造器  
public GamePanel() {  
    init();  
    this.setFocusable(true);  
    this.addKeyListener(this);  
    timer.start();  
}

//初始化方法  
public void init() {  
    length = 3;  
    snakeX\[0\] = 100;  
    snakeY\[0\] = 100;  
    snakeX\[1\] = 75;  
    snakeY\[1\] = 100;  
    snakeX\[2\] = 50;  
    snakeY\[2\] = 100;  
    foodX = 25 + 25 \* random.nextInt(34);  
    foodY = 75 + 25 \* random.nextInt(24);  
    score = 0;  
}

//食物坐标生成

@Override  
protected void paintComponent(Graphics g) {  
    super.paintComponent(g);  
    this.setBackground(Color.white);

    Data.header.paintIcon(this, g, 25, 11);//顶部广告栏

    g.fillRect(25, 75, 850, 600);

    //绘制静态的蛇  
    if (fx.equals("R")) {  
        Data.right.paintIcon(this, g, snakeX\[0\], snakeY\[0\]);  
    } else if (fx.equals("L")) {  
        Data.left.paintIcon(this, g, snakeX\[0\], snakeY\[0\]);  
    } else if (fx.equals("U")) {  
        Data.up.paintIcon(this, g, snakeX\[0\], snakeY\[0\]);  
    } else if (fx.equals("D")) {  
        Data.down.paintIcon(this, g, snakeX\[0\], snakeY\[0\]);  
    }  
    for (int i = 1; i < length; i++) {  
        Data.body.paintIcon(this, g, snakeX\[i\], snakeY\[i\]);  
    }

    //积分系统  
    g.setColor(Color.white);  
    g.setFont(new Font("微软雅黑", Font.BOLD, 18));  
    g.drawString("长度：" + length, 750, 35);  
    g.drawString("分数：" + score, 750, 50);

    //绘制食物  
    Data.food.paintIcon(this, g, foodX, foodY);

    //游戏开始判断  
    if (isStart == false) {  
        g.setColor(Color.white);  
        g.setFont(new Font("微软雅黑", Font.BOLD, 40));//设置字体格式  
        g.drawString("按下空格键开始游戏", 300, 350);  
    }

    //游戏失败判断  
    if (isFail) {  
        g.setColor(Color.red);  
        g.setFont(new Font("微软雅黑", Font.BOLD, 40));//设置字体格式  
        g.drawString("游戏失败，按下空格键重新开始", 175, 350);  
    }  
}

@Override  
public void keyPressed(KeyEvent e) {  
    int keyCode = e.getKeyCode();

    if (keyCode == KeyEvent.VK\_SPACE) {  
        if (isFail) {  
            isFail = false;  
            init();//重新初始化游戏  
        } else {  
            isStart = !isStart;  
        }  
        repaint();//刷新  
    }

    if (keyCode == KeyEvent.VK\_LEFT) {  
        fx = "L";  
    } else if (keyCode == KeyEvent.VK\_RIGHT) {  
        fx = "R";  
    } else if (keyCode == KeyEvent.VK\_UP) {  
        fx = "U";  
    } else if (keyCode == KeyEvent.VK\_DOWN) {  
        fx = "D";  
    }  
}

@Override  
public void keyTyped(KeyEvent e) {

}

@Override  
public void keyReleased(KeyEvent e) {

}

@Override  
public void actionPerformed(ActionEvent e) {  
    if (isStart && isFail == false) {  
        for (int i = length - 1; i > 0; i--) {  
            snakeX\[i\] = snakeX\[i - 1\];  
            snakeY\[i\] = snakeY\[i - 1\];  
        }  
        if (fx.equals("R")) {  
            snakeX\[0\] = snakeX\[0\] + 25;  
            //边界判断  
            if (snakeX\[0\] > 850) {  
                snakeX\[0\] = 25;  
            }  
        } else if (fx.equals("L")) {  
            snakeX\[0\] = snakeX\[0\] - 25;  
            //边界判断  
            if (snakeX\[0\] < 25) {  
                snakeX\[0\] = 850;  
            }  
        } else if (fx.equals("U")) {  
            snakeY\[0\] = snakeY\[0\] - 25;  
            //边界判断  
            if (snakeY\[0\] < 75) {  
                snakeY\[0\] = 650;  
            }  
        } else if (fx.equals("D")) {  
            snakeY\[0\] = snakeY\[0\] + 25;  
            //边界判断  
            if (snakeY\[0\] > 650) {  
                snakeY\[0\] = 75;  
            }  
        }

        //是否吃到食物判断  
        if (snakeX\[0\] == foodX && snakeY\[0\] == foodY) {  
            length++;//长度增加

            //新的食物生成  
            foodX = 25 + 25 \* random.nextInt(34);  
            foodY = 75 + 25 \* random.nextInt(24);

            score += 10;//增加积分  
        }

        //结束判断  
        for (int i = 1; i < length; i++) {  
            if (snakeX\[0\] == snakeX\[i\] && snakeY\[0\] == snakeY\[i\]) {  
                isFail = true;  
            }  
        }  
        repaint();//刷新  
    }  
    timer.start();  
}  

}

以上是游戏面板以及游戏其他主体部分的实现

在初始阶段绘制一条固定位置的静态小蛇与屏幕中部的“按下空格开始游戏”提示

利用事件监听获得按键方向从而控制小蛇移动

小蛇的移动是通过坐标复制实现的，即数组从末尾往起始位置复制，使用repaint方法刷新画面，画出新的画，可以通过定时器Timer来控制刷新的间隔长

明天学习网络编程部分的知识