贪吃蛇小游戏

谁借莪１个温暖的怀抱￠ 2023-01-02 08:28 271阅读 0赞

贪吃蛇游戏是一款比较经典的休闲游戏，文章包括项目的部分源码以及运行界面的一些图片，项目也参考学习了许多大佬的文章，会在文章最后面贴出参考文章，有什么问题也请大家指正。

### 一、游戏界面及游戏简介 ###

![游戏界面][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center]

说明：点击【START】开始游戏，点击【UP】【DOWN】【LEFT】【RIGHT】分别实现蛇头向【上】【下】【左】【右】方向移动，若蛇头位置超过边界则从另一侧穿出，若蛇头碰到随机生成的食物（及蓝色小方块）则蛇长增加；若蛇头碰撞到自己身上的部位，则视为蛇死亡，游戏结束！

### 二、游戏界面的布局xml ###

![布局][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 1]

此布局使用的是ConstraintLayout约束性布局，实现基础游戏界面布局

代码如下

<?xml version="1.0" encoding="utf-8"?>
    <androidx.constraintlayout.widget.ConstraintLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context="com.example.snack.MainActivity">
    
      <com.example.snack.SnakePanelView
          android:id="@+id/snake_view"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:orientation="horizontal"
          android:layout_marginTop="4dp"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toTopOf="parent" />
    
      <Button
          android:id="@+id/top_btn"
          android:layout_width="75dp"
          android:layout_height="45dp"
          android:layout_marginTop="28dp"
          android:background="@drawable/direction_btn_background"
          android:text="UP"
          android:textColor="@android:color/white"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintHorizontal_bias="0.532"
          app:layout_constraintLeft_toLeftOf="parent"
          app:layout_constraintRight_toRightOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/snake_view" />
    
      <Button
          android:id="@+id/left_btn"
          android:layout_width="75dp"
          android:layout_height="45dp"
          android:layout_marginStart="16dp"
          android:layout_marginTop="16dp"
          android:background="@drawable/direction_btn_background"
          android:text="LEFT"
          android:textColor="@android:color/white"
          app:layout_constraintEnd_toStartOf="@+id/top_btn"
          app:layout_constraintHorizontal_bias="0.659"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/top_btn" />
    
      <Button
          android:id="@+id/right_btn"
          android:layout_width="75dp"
          android:layout_height="45dp"
          android:layout_marginTop="8dp"
          android:layout_marginEnd="24dp"
          android:background="@drawable/direction_btn_background"
          android:text="RIGHT"
          android:textColor="@android:color/white"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintHorizontal_bias="0.565"
          app:layout_constraintStart_toEndOf="@+id/top_btn"
          app:layout_constraintTop_toTopOf="@+id/left_btn" />
    
      <Button
          android:id="@+id/bottom_btn"
          android:layout_width="75dp"
          android:layout_height="45dp"
          android:layout_marginBottom="24dp"
          android:background="@drawable/direction_btn_background"
          android:text="DOWN"
          android:textColor="@android:color/white"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintHorizontal_bias="0.532"
          app:layout_constraintLeft_toLeftOf="parent"
          app:layout_constraintRight_toRightOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/top_btn"
          app:layout_constraintVertical_bias="0.334" />
    
      <Button
          android:id="@+id/start_btn"
          android:layout_width="75dp"
          android:layout_height="45dp"
          android:layout_marginStart="36dp"
          android:layout_marginTop="8dp"
          android:background="@drawable/restart_btn_background"
          android:text="START"
          android:textColor="@android:color/white"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/snake_view" />
    
    </androidx.constraintlayout.widget.ConstraintLayout>

### 三、生成食物 ###

随机生成，但不能生成在蛇身上。食物（蓝色小方块）是通过random产生随机坐标，存放到食物的Arraylist中，然后调用父类的方法将图片画在view上。  
![食物][2021010123294464.png_pic_center]

//生成food
      private void generateFood() {
        Random random = new Random();
        int foodX = random.nextInt(mGridSize - 1);
        int foodY = random.nextInt(mGridSize - 1);
        for (int i = 0; i < mSnakePositions.size() - 1; i++) {
          if (foodX == mSnakePositions.get(i).getX() && foodY == mSnakePositions.get(i).getY()) {
       
            foodX = random.nextInt(mGridSize - 1);
            foodY = random.nextInt(mGridSize - 1);
            //如果生成在蛇身上则重新循环
            i = 0;
          }
        }
        mFoodPosition.setX(foodX);
        mFoodPosition.setY(foodY);
        refreshFood(mFoodPosition);
      }

### 四、蛇的移动 ###

蛇的移动是通过界面的重新绘制实现的，点击方向键就改变蛇头的坐标，往某一方向进行x坐标或y坐标的增加。通过遍历食物和障碍物的Arraylist进行检测是否吃到食物或撞到障碍物，如果超过边界坐标，则从另一边穿出。  
![按方向键改变蛇头移动方向][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 2]

![穿出][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 3]

private void moveSnake(int snakeDirection) {
        switch (snakeDirection) {
          case GameType.LEFT:
            if (mSnakeHeader.getX() - 1 < 0) {//边界判断：如果到了最左边 让他穿过屏幕到最右边
              mSnakeHeader.setX(mGridSize - 1);
            } else {
              mSnakeHeader.setX(mSnakeHeader.getX() - 1);
            }
            mSnakePositions.add(new GridPosition(mSnakeHeader.getX(), mSnakeHeader.getY()));
            break;
          case GameType.TOP:
            if (mSnakeHeader.getY() - 1 < 0) {
              mSnakeHeader.setY(mGridSize - 1);
            } else {
              mSnakeHeader.setY(mSnakeHeader.getY() - 1);
            }
            mSnakePositions.add(new GridPosition(mSnakeHeader.getX(), mSnakeHeader.getY()));
            break;
          case GameType.RIGHT:
            if (mSnakeHeader.getX() + 1 >= mGridSize) {
              mSnakeHeader.setX(0);
            } else {
              mSnakeHeader.setX(mSnakeHeader.getX() + 1);
            }
            mSnakePositions.add(new GridPosition(mSnakeHeader.getX(), mSnakeHeader.getY()));
            break;
          case GameType.BOTTOM:
            if (mSnakeHeader.getY() + 1 >= mGridSize) {
              mSnakeHeader.setY(0);
            } else {
              mSnakeHeader.setY(mSnakeHeader.getY() + 1);
            }
            mSnakePositions.add(new GridPosition(mSnakeHeader.getX(), mSnakeHeader.getY()));
            break;
        }
      }

### 五、判断碰撞（生或死） ###

通过遍历食物和障碍物的Arraylist进行检测是否吃到食物或撞到自己，若撞到自己则游戏结束。  
![游戏结束][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 4]

private void checkCollision() {
        //检测是否咬到自己
        GridPosition headerPosition = mSnakePositions.get(mSnakePositions.size() - 1);
        for (int i = 0; i < mSnakePositions.size() - 2; i++) {
          GridPosition position = mSnakePositions.get(i);
          if (headerPosition.getX() == position.getX() && headerPosition.getY() == position.getY()) {
            //咬到自己 停止游戏
            mIsEndGame = true;
            showMessageDialog();
            return;
          }
        }
    
        //判断是否吃到食物，吃到食物蛇长加一，游戏继续
        if (headerPosition.getX() == mFoodPosition.getX()
            && headerPosition.getY() == mFoodPosition.getY()) {
          mSnakeLength++;
          generateFood();
        }
      }
      
      
     //结束游戏的弹窗 
      private void showMessageDialog() {
        post(new Runnable() {
          @Override
          public void run() {
            new AlertDialog.Builder(getContext()).setMessage("Game " + "Over!")
                .setCancelable(false)
                .setPositiveButton("重新开始", new DialogInterface.OnClickListener() {
                  @Override
                  public void onClick(DialogInterface dialog, int which) {
                    dialog.dismiss();
                    reStartGame();
                  }
                })
                .setNegativeButton("退出", new DialogInterface.OnClickListener() {
                  @Override
                  public void onClick(DialogInterface dialog, int which) {
                    dialog.dismiss();
                  }
                })
                .create()
                .show();
          }
        });
      }

### 六、Mainactivity ###

在窗体中设置一些按键的监听

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    
      private SnakePanelView mSnakePanelView;
    
      @Override
      protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    
        mSnakePanelView = findViewById(R.id.snake_view);
    
        findViewById(R.id.left_btn).setOnClickListener(this);
        findViewById(R.id.right_btn).setOnClickListener(this);
        findViewById(R.id.top_btn).setOnClickListener(this);
        findViewById(R.id.bottom_btn).setOnClickListener(this);
        findViewById(R.id.start_btn).setOnClickListener(this);
      }
    
      @Override
      public void onClick(View v) {
        switch (v.getId()) {
          case R.id.left_btn:
            mSnakePanelView.setSnakeDirection(GameType.LEFT);
            break;
          case R.id.right_btn:
            mSnakePanelView.setSnakeDirection(GameType.RIGHT);
            break;
          case R.id.top_btn:
            mSnakePanelView.setSnakeDirection(GameType.TOP);
            break;
          case R.id.bottom_btn:
            mSnakePanelView.setSnakeDirection(GameType.BOTTOM);
            break;
          case R.id.start_btn:
            mSnakePanelView.reStartGame();
            break;
        }
      }
    }

[参考文章][Link 1]

作者：刘淑慧  
[原文地址][Link 2]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center]: /images/20221120/d69a6ba203674cb0913122e976b70e15.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221120/c2a717f8344b45e78894cd58e60e7990.png
[2021010123294464.png_pic_center]: /images/20221120/8a31189b1db84f97b57c783efe0c7ab6.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 2]: /images/20221120/652a2f974b0b46fca93ef94729e6038b.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 3]: /images/20221120/c48b8f74492f4f0c9d3f8b73e902b1d8.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NTczODA2OQ_size_16_color_FFFFFF_t_70_pic_center 4]: /images/20221120/a5730525ff8141bcb0b2852538a04df8.png
[Link 1]: https://blog.csdn.net/weixin_44799020/article/details/107295624?utm_medium=distribute.pc_relevant.none-task-blog-OPENSEARCH-2.control&depth_1-utm_source=distribute.pc_relevant.none-task-blog-OPENSEARCH-2.control
[Link 2]: https://blog.csdn.net/weixin_45738069/article/details/112079482