Qt实战项目——贪吃蛇

一、项目介绍

本项目是一个使用Qt框架开发的经典贪吃蛇游戏，旨在通过简单易懂的游戏机制和精美的用户界面，为玩家提供娱乐和编程学习的机会。

游戏展示

二、主要功能

2.1 游戏界面

游戏主要是由三个界面构成，分别是游戏大厅、难度选择和游戏内界面，因此需要建立三个.cpp文件，分别对应的是gamehall.cpp、gameselect.cpp和gameroom.cpp。

2.1.1 gamehall.cpp

在游戏大厅界面，需要将图片设置到背景板上，并且创建一个"开始游戏"按钮

GameHall::GameHall(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::GameHall)
{
    ui->setupUi(this);

    // 设置窗口大小、图标、名字
    this->setFixedSize(1080,720);
    this->setWindowIcon(QIcon(":Resource/icon.png"));
    this->setWindowTitle("贪吃蛇大作战");

    // 设置开始按钮
    QFont font("华文行楷",18);
    QPushButton* pushButton_start = new QPushButton(this);
    pushButton_start->setText("开始游戏");
    pushButton_start->setFont(font);
    pushButton_start->move(520,400);
    pushButton_start->setGeometry(440,520,160,90);
    pushButton_start->setStyleSheet("QPushButton{border:0px;}");

    // 点击"开始游戏"按钮进入难度选择界面
    GameSelect* gameSelect = new GameSelect;
    connect(pushButton_start,&QPushButton::clicked,[=](){
       this->close();
       gameSelect->setGeometry(this->geometry());
       gameSelect->show();

       QSound::play(":Resource/clicked.wav");
    });
}

GameHall::~GameHall()
{
    delete ui;
}

void GameHall::paintEvent(QPaintEvent *event)
{
    (void) *event;
    // 实例化画家
    QPainter painter(this);

    // 实例化绘图设备
    QPixmap pix(":Resource/game_hall.png");

    // 绘图
    painter.drawPixmap(0,0,this->width(),this->height(),pix);
}

2.1.2 gameselect.cpp

在游戏选择界面中，同样是需要设置背景，创建按钮等操作。

其中点击"简单模式"、"正常模式"、"困难模式"可以直接进入游戏房间内，而查阅"历史战绩"时会弹出一个新窗口显示战绩。

GameSelect::GameSelect(QWidget *parent) : QWidget(parent)
{
    // 设置"难度选择"界面的图标、名字
    this->setFixedSize(1080,720);
    this->setWindowIcon(QIcon(":Resource/icon.png"));
    this->setWindowTitle("难度选择");

    QFont font("华文行楷",24);
    GameRoom* gameRoom = new GameRoom;

    // 设置选择难度按钮和历史战绩按钮
    QPushButton* pushButton_easy = new QPushButton(this);
    pushButton_easy->move(460,160);
    pushButton_easy->setGeometry(460,160,150,80);
    pushButton_easy->setText("简单模式");
    pushButton_easy->setFont(font);
    pushButton_easy->setStyleSheet("QPushButton{border:0px;color:white}");

    QPushButton* pushButton_normal = new QPushButton(this);
    pushButton_normal->move(460,280);
    pushButton_normal->setGeometry(460,280,150,80);
    pushButton_normal->setText("正常模式");
    pushButton_normal->setFont(font);
    pushButton_normal->setStyleSheet("QPushButton{border:0px;color:white}");

    QPushButton* pushButton_hard = new QPushButton(this);
    pushButton_hard->move(460,400);
    pushButton_hard->setGeometry(460,400,150,80);
    pushButton_hard->setText("困难模式");
    pushButton_hard->setFont(font);
    pushButton_hard->setStyleSheet("QPushButton{border:0px;color:white}");

    QPushButton* pushButton_record = new QPushButton(this);
    pushButton_record->move(460,520);
    pushButton_record->setGeometry(460,520,150,80);
    pushButton_record->setText("历史战绩");
    pushButton_record->setFont(font);
    pushButton_record->setStyleSheet("QPushButton{border:0px;color:white}");

    // 点击不同困难模式按钮进入游戏房间
    connect(pushButton_easy,&QPushButton::clicked,[=](){
        this->close();
        gameRoom->setGeometry(this->geometry());
        gameRoom->show();
        QSound::play(":Resource/clicked.wav");
        gameRoom->setTimeout(300);
    });

    connect(pushButton_normal,&QPushButton::clicked,[=](){
        this->close();
        gameRoom->setGeometry(this->geometry());
        gameRoom->show();
        QSound::play(":Resource/clicked.wav");
        gameRoom->setTimeout(200);
    });

    connect(pushButton_hard,&QPushButton::clicked,[=](){
        this->close();
        gameRoom->setGeometry(this->geometry());
        gameRoom->show();
        QSound::play(":Resource/clicked.wav");
        gameRoom->setTimeout(100);
    });

    // 设置历史战绩窗口
    connect(pushButton_record,&QPushButton::clicked,[=](){
        QWidget* widget = new QWidget;
        widget->setWindowTitle("历史战绩");
        widget->setWindowIcon(QIcon(":Resource/icon.png"));
        widget->setFixedSize(500,300);
        QSound::play(":Resource/clicked.wav");

        QTextEdit* edit = new QTextEdit(widget);
        edit->setFont(font);
        edit->setFixedSize(500,300);

        QFile file("D:/bite/C-program/project/Snake/gamedata.txt");
        file.open(QIODevice::ReadOnly);

        QTextStream in(&file);
        int data = in.readLine().toInt();
        edit->append("历史得分为：");
        edit->append(QString::number(data));

        widget->show();
    });
}

void GameSelect::paintEvent(QPaintEvent *event)
{
    (void) *event;
    QPainter painter(this);
    QPixmap pix(":Resource/game_select.png");
    painter.drawPixmap(0,0,this->width(),this->height(),pix);
}

同时在这个界面中，我们需要创建一个"回退"按钮，点击可回退到游戏大厅界面

    // 设置回退按钮
    QPushButton* pushButton_back = new QPushButton(this);
    pushButton_back->move(1000,640);
    pushButton_back->setGeometry(1000,640,60,60);
    pushButton_back->setIcon(QIcon(":Resource/back.png"));

    // 点击回退按钮回到上一页
    connect(pushButton_back,&QPushButton::clicked,[=](){
        this->close();
        GameHall* gameHall = new GameHall;
        gameHall->show();
        QSound::play(":Resource/clicked.wav");
    });

2.1.3 gameroom.cpp

在游戏房间界面中，我们可以看到许多元素，其中不仅有"开始"、"暂停"、"退出"三个按钮，还有控制小蛇移动的方向键按钮，还有计分板等等元素。

我们首先要做的是设计背景以及创建各个按钮。

    // 设置游戏房间大小、图标、名字
    this->setFixedSize(1080,720);
    this->setWindowIcon(QIcon(":Resource/icon.png"));
    this->setWindowTitle("游戏房间");

    // 开始游戏、暂停游戏
    QFont font("楷体",20);

    QPushButton* pushButton_start = new QPushButton(this);
    pushButton_start->move(890,460);
    pushButton_start->setGeometry(890,460,100,60);
    pushButton_start->setText("开始");
    pushButton_start->setFont(font);
    connect(pushButton_start,&QPushButton::clicked,[=](){
        isGameStart = true;
        timer->start(moveTimeout);
        sound = new QSound(":Resource/Trepak.wav");
        sound->play();
        sound->setLoops(-1);
    });

    QPushButton* pushButton_stop = new QPushButton(this);
    pushButton_stop->move(890,540);
    pushButton_stop->setGeometry(890,540,100,60);
    pushButton_stop->setText("暂停");
    pushButton_stop->setFont(font);
    connect(pushButton_stop,&QPushButton::clicked,[=](){
        isGameStart = false;
        timer->stop();
        sound->stop();
    });

    // 设置方向键的位置、大小、图标和快捷键
    QPushButton* pushButton_up = new QPushButton(this);
    pushButton_up->move(900,220);
    pushButton_up->setGeometry(900,220,80,60);
    pushButton_up->setIcon(QIcon(":Resource/up1.png"));
    connect(pushButton_up,&QPushButton::clicked,[=](){
        if(moveDirect != SnakeDirect::DOWN)
            moveDirect = SnakeDirect::UP;
    });
    pushButton_up->setShortcut(QKeySequence(Qt::Key_W));

    QPushButton* pushButton_down = new QPushButton(this);
    pushButton_down->move(900,340);
    pushButton_down->setGeometry(900,340,80,60);
    pushButton_down->setIcon(QIcon(":Resource/down1.png"));
    connect(pushButton_down,&QPushButton::clicked,[=](){
        if(moveDirect != SnakeDirect::UP)
            moveDirect = SnakeDirect::DOWN;
    });
    pushButton_down->setShortcut(QKeySequence(Qt::Key_S));

    QPushButton* pushButton_left = new QPushButton(this);
    pushButton_left->move(820,280);
    pushButton_left->setGeometry(820,280,80,60);
    pushButton_left->setIcon(QIcon(":Resource/left1.png"));
    connect(pushButton_left,&QPushButton::clicked,[=](){
        if(moveDirect != SnakeDirect::RIGHT)
            moveDirect = SnakeDirect::LEFT;
    });
    pushButton_left->setShortcut(QKeySequence(Qt::Key_A));

    QPushButton* pushButton_right = new QPushButton(this);
    pushButton_right->move(980,280);
    pushButton_right->setGeometry(980,280,80,60);
    pushButton_right->setIcon(QIcon(":Resource/right1.png"));
    connect(pushButton_right,&QPushButton::clicked,[=](){
        if(moveDirect != SnakeDirect::LEFT)
            moveDirect = SnakeDirect::RIGHT;
    });
    pushButton_right->setShortcut(QKeySequence(Qt::Key_D));

    // 设置退出按钮
    QPushButton* pushButton_exit = new QPushButton(this);
    pushButton_exit->move(890,620);
    pushButton_exit->setGeometry(890,620,100,60);
    pushButton_exit->setText("退出");
    pushButton_exit->setFont(font);

2.2 游戏规则

蛇移动时不能碰到自己的身体，否则游戏结束。每吃掉一个食物（食物会随机刷新），身体变长，分数增加。

    // 初始化贪吃蛇
    snakeList.push_back(QRectF(this->width() * 0.5,this->height() * 0.5,kSnakeNodeWight,kSnakeNodeHeight));

    moveUP();
    moveUP();

    creatFood();

    timer = new QTimer(this);
    connect(timer,&QTimer::timeout,[=](){
        int count = 1;
        if(snakeList.front().intersects(foodRect))
        {
            creatFood();
            count++;
            QSound::play(":Resource/eatfood.wav");
        }

        while(count--)
        {
            switch(moveDirect)
            {
            case SnakeDirect::UP:
                moveUP();
                break;
            case SnakeDirect::DOWN:
                moveDOWN();
                break;
            case SnakeDirect::LEFT:
                moveLEFT();
                break;
            case SnakeDirect::RIGHT:
                moveRIGHT();
                break;
            }
        }

        snakeList.pop_back();
        update();
    });

    // 绘制蛇
    if(moveDirect == SnakeDirect::UP)
    {
        pix.load(":Resource/up.png");
    }
    else if(moveDirect == SnakeDirect::DOWN)
    {
        pix.load(":Resource/down.png");
    }
    else if(moveDirect == SnakeDirect::LEFT)
    {
        pix.load(":Resource/left.png");
    }
    else
    {
        pix.load(":Resource/right.png");
    }

    // 绘制蛇头、身体和尾巴
    auto Head = snakeList.front();
    painter.drawPixmap(Head.x(),Head.y(),Head.width(),Head.height(),pix);

    pix.load(":Resource/Bd.png");
    for (int i = 0;i < snakeList.size() - 1;i++)
    {
        auto Body = snakeList.at(i);
        painter.drawPixmap(Body.x(),Body.y(),Body.width(),Body.height(),pix);
    };

    auto tail = snakeList.back();
    painter.drawPixmap(tail.x(),tail.y(),tail.width(),tail.height(),pix);

    // 绘制食物
    pix.load(":Resource/food.png");
    painter.drawPixmap(foodRect.x(),foodRect.y(),foodRect.width(),foodRect.height(),pix);

bool GameRoom::checkFail()
{
    for(int i = 0;i < snakeList.size();i++)
    {
        for(int j = i + 1;j < snakeList.size();j++)
        {
            if(snakeList.at(i) == snakeList.at(j))
            {
                return true;
            }
        }
    }
    return false;
}

void GameRoom::creatFood()
{
    foodRect = QRectF(qrand() % (800 / kSnakeNodeWight) * kSnakeNodeWight,
                      qrand() % (this->height() / kSnakeNodeHeight) * kSnakeNodeHeight,
                      kSnakeNodeWight,kSnakeNodeHeight);
}

2.3 控制方式

使用界面上的方向键（上、下、左、右）或者通过键盘上的快捷键（W、S、A、D）来控制蛇的移动方向，但不能直接反向移动。

void GameRoom::moveUP()
{
    QPointF leftTop;
    QPointF rightBottom;

    // 蛇头
    auto snakeNode = snakeList.front();
    int headX = snakeNode.x();
    int headY = snakeNode.y();

    // 如果穿模
    if(headY < 20)
    {
        leftTop = QPointF(headX,this->height() - kSnakeNodeHeight);
    }
    else
    {
        leftTop = QPointF(headX,headY - kSnakeNodeHeight);
    }

    rightBottom = leftTop + QPointF(kSnakeNodeWight,kSnakeNodeHeight);

    snakeList.push_front(QRectF(leftTop,rightBottom));
}

void GameRoom::moveDOWN()
{
    QPointF leftTop;
    QPointF rightBottom;

    auto snakeNode = snakeList.front();
    int headX = snakeNode.x();
    int headY = snakeNode.y();

    if(headY > this->height())
    {
        leftTop = QPointF(headX,0);
    }
    else
    {
        leftTop = snakeNode.bottomLeft();
    }

    rightBottom = leftTop + QPointF(kSnakeNodeWight,kSnakeNodeHeight);

    snakeList.push_front(QRectF(leftTop,rightBottom));
}

void GameRoom::moveLEFT()
{
    QPointF leftTop;
    QPointF rightBottom;

    auto snakeNode = snakeList.front();
    int headX = snakeNode.x();
    int headY = snakeNode.y();

    if(headX < 0)
    {
        leftTop = QPointF(800 - kSnakeNodeWight,headY);
    }
    else
    {
        leftTop = QPointF(headX - kSnakeNodeWight,headY);
    }

    rightBottom = leftTop + QPointF(kSnakeNodeWight,kSnakeNodeHeight);
    snakeList.push_front(QRectF(leftTop,rightBottom));
}

void GameRoom::moveRIGHT()
{
    QPointF leftTop;
    QPointF rightBottom;

    auto snakeNode = snakeList.front();
    int headX = snakeNode.x();
    int headY = snakeNode.y();

    if(headX > 760)
    {
        leftTop = QPointF(0,headY);
    }
    else
    {
        leftTop = snakeNode.topRight();
    }

    rightBottom = leftTop + QPointF(kSnakeNodeWight,kSnakeNodeHeight);
    snakeList.push_front(QRectF(leftTop,rightBottom));
}

三、结语

这个项目比较简单，通过这个项目，不仅可以学习到Qt的GUI开发和事件处理技术，还能熟悉C++编程及基本的游戏开发概念。关于Qt中的一些基础知识，我也会在后续逐步更新。

好了，源码我会放在下面，大家有兴趣的可以看一看，欢迎大家一键三连！！！

四、源码

https://gitee.com/hu-jiahao143/project/commit/f83b287c800dd105f8358d7ffb244202ebf015c9