五、Qt综合项目-局域网聊天室

1.项目介绍

最后我们可以使用Qt做一个局域网聊天室

好友列表页面如下：

首页展示好友列表，点击好友进入聊天界面

聊天界面如下：

聊天界面可以显示展示进入局域网好友列表

有新用户进入，提示新用户进入

用户离开，提示用户离开

发送消息可以发送给所有在线的用户

2. 主界面

#include "MainWindow.h"

MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent) {
    //设置大小
    setFixedSize(250, 700);
    //设置标题
    setWindowTitle("QQ");
    //设置图标
    setWindowIcon(QIcon(":/images/qq.png"));
    //初始化界面
    initUI();
}

MainWindow::~MainWindow() {

}

//初始化界面
void MainWindow::initUI() {
    auto *tb = new QToolBox;
    auto *gb = new QGroupBox;
    auto *vl = new QVBoxLayout;
    //添加条目
    tb->addItem(gb, "联系人");
    gb->setLayout(vl);
    //添加中心控件
    setCentralWidget(tb);
    //创建联系人条目
    createContacts(vl);
    //每个窗口是否显示
    for (int i = 0; i < btns.size(); ++i) {
        isShows.append(false);
    }
    //处理每一个按钮的事件
    contactsClick();
}

//创建联系人条目
void MainWindow::createContacts(QVBoxLayout *const &layout) {
    QList<QString> nameList{"Maker", "水票奇缘", "忆梦如澜", "北京出版人", "Cherry", "淡然", "娇娇girl", "落水无痕",
                            "青墨暖暖"};
    QStringList iconList{"qt", "spqy", "ymrl", "qq", "Cherry", "dr", "jj", "lswh", "qmnn"};
    for (int i = 0; i < nameList.size(); ++i) {
        //创建按钮
        auto *btn = new QToolButton();
        //添加文字
        btn->setText(nameList[i]);
        //添加图片
        auto *icon = new QPixmap(QString(":/images/%1.png").arg(iconList[i]));
        btn->setIcon(*icon);

        //设置样式
        btn->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
        //设置按钮大小
        btn->resize(210, 70);
        //按钮图片大小
        btn->setIconSize(icon->size());
        //设置透明度
        btn->setAutoRaise(true);
        //添加到布局中
        layout->addWidget(btn);
        //添加到按钮的列表中
        btns.append(btn);
    }
}

//处理每一个按钮的点击事件
void MainWindow::contactsClick() {
    for (int i = 0; i < btns.size(); ++i) {
        QToolButton *btn = btns[i];
        connect(btn, &QToolButton::clicked, [=]() {
            if (!isShows[i]) {
                //创建会话窗口
                auto *w = new ConversationWindow(btn->text());
                //设置标题和图标
                w->setWindowTitle(btn->text());
                w->setWindowIcon(btn->icon());
                //设置显示属性
                w->setAttribute(Qt::WA_DeleteOnClose);
                w->show();
                //改变显示标记
                isShows[i] = true;
                //关闭的回调
                connect(w,&ConversationWindow::conversationClose,[=](){
                    isShows[i] = false;
                });
            }
        });
    }
}

3. 聊天界面

#include "ConversationWindow.h"

ConversationWindow::ConversationWindow(QString name, QWidget *parent) : QMainWindow(parent), name(name) {
    //设置界面大小
    this->resize(740, 450);
    //初始化界面
    initUI();
    //按钮的点击事件
    btnsClick();
    //信息相关的操作
    socketOperator();
}

ConversationWindow::~ConversationWindow() {

}

//初始化界面
void ConversationWindow::initUI() {
    //整体竖直布局
    QVBoxLayout *wholeLayout = new QVBoxLayout;
    //左侧竖直布局
    QVBoxLayout *leftLayout = new QVBoxLayout;
    //右侧TableWidget
    tw = new QTableWidget(0, 1);
    tw->setMaximumWidth(180);

    tw->setHorizontalHeaderLabels(QStringList{"用户名"});

    //上部布局
    QHBoxLayout *upLayout = new QHBoxLayout;
    //下部布局
    QHBoxLayout *downLayout = new QHBoxLayout;
    //发送按钮
    sendBtn = new QPushButton;
    sendBtn->setText("发送");
    //在线人数
    label = new QLabel;
    label->setText("在线人数:1");
    //退出按钮
    exitBtn = new QPushButton;
    exitBtn->setText("退出");


    //左侧
    //1.消息显示框
    msgEdit = new QTextEdit;
    msgEdit->setReadOnly(true);
    //2.水平布局(字体等)
    QHBoxLayout *iconLayout = new QHBoxLayout;
    //3.发送消息输入框
    sendEdit = new QTextEdit;

    //图标
    //1.宋体
    fontBox = new QFontComboBox;
    //2.字体大小
    fontSizeBox = new QComboBox;
    //3.字体加粗
    blod = new QToolButton;
    //4.斜体
    italic = new QToolButton;
    //5.下划线
    underLine = new QToolButton;
    //6.更改字体颜色
    fontColor = new QToolButton;
    //7.保存聊天记录
    saveConversation = new QToolButton;
    //8.清空聊天记录
    clearConversation = new QToolButton;

    //设置加粗、斜体和下划线可以选中
    blod->setCheckable(true);
    italic->setCheckable(true);
    underLine->setCheckable(true);

    //添加图标布局
    iconLayout->addWidget(fontBox);
    iconLayout->addWidget(fontSizeBox);
    iconLayout->addWidget(blod);
    iconLayout->addWidget(italic);
    iconLayout->addWidget(underLine);
    iconLayout->addWidget(fontColor);
    iconLayout->addWidget(saveConversation);
    iconLayout->addWidget(clearConversation);

    //添加左侧
    leftLayout->addWidget(msgEdit);
    leftLayout->addLayout(iconLayout);
    leftLayout->addWidget(sendEdit);

    //上部布局
    upLayout->addLayout(leftLayout);
    upLayout->addWidget(tw);
    //下部布局
    downLayout->addStretch(1);
    downLayout->addWidget(sendBtn);
    downLayout->addStretch(1);
    downLayout->addWidget(label);
    downLayout->addStretch(1);
    downLayout->addWidget(exitBtn);
    downLayout->addStretch(1);

    //整体布局添加
    wholeLayout->addLayout(upLayout);
    wholeLayout->addLayout(downLayout);

    //设置中心控件
    QWidget *w = new QWidget;
    w->setLayout(wholeLayout);
    setCentralWidget(w);


    //处理细节
    //1.字体大小
    fontSizeBox->addItem("12");
    fontSizeBox->addItem("13");
    fontSizeBox->addItem("14");
    fontSizeBox->addItem("15");
    //2.图标
    blod->setIconSize(QSize(26, 26));
    italic->setIconSize(QSize(26, 26));
    underLine->setIconSize(QSize(26, 26));
    fontColor->setIconSize(QSize(26, 26));
    saveConversation->setIconSize(QSize(26, 26));
    clearConversation->setIconSize(QSize(26, 26));
    //加粗
    blod->setIcon(QPixmap(":/images/bold.png"));
    italic->setIcon(QPixmap(":/images/italic.png"));
    underLine->setIcon(QPixmap(":/images/under.png"));
    fontColor->setIcon(QPixmap(":/images/color.png"));
    saveConversation->setIcon(QPixmap(":/images/save.png"));
    clearConversation->setIcon(QPixmap(":/images/clear.png"));
}

//按钮信号和槽函数
void ConversationWindow::btnsClick() {
    //字体设置
    connect(fontBox, &QFontComboBox::currentFontChanged, [=](const QFont &font) {
        sendEdit->setFont(font);
    });
    //字体大小设置
    void (QComboBox::*currentIndexChanged)(const QString &text) = &QComboBox::currentIndexChanged;
    connect(fontSizeBox, currentIndexChanged, [=](const QString &text) {
        sendEdit->setFontPointSize(text.toDouble());
    });
    //字体加粗
    connect(blod, &QToolButton::clicked, [=](bool checked = false) {
        if (checked) {
            sendEdit->setFontWeight(QFont::Bold);
        } else {
            sendEdit->setFontWeight(QFont::Normal);
        }
    });
    //斜体
    connect(italic, &QToolButton::clicked, [=](bool checked = false) {
        if (checked) {
            sendEdit->setFontItalic(true);
        } else {
            sendEdit->setFontItalic(false);
        }
    });
    //下划线
    connect(underLine, &QToolButton::clicked, [=](bool checked = false) {
        if (checked) {
            sendEdit->setFontUnderline(true);
        } else {
            sendEdit->setFontUnderline(false);
        }
    });
    //选择颜色
    connect(fontColor, &QPushButton::clicked, [=]() {
        QColor color = QColorDialog::getColor();
        sendEdit->setTextColor(color);
    });
    //保存聊天记录
    connect(saveConversation, &QToolButton::clicked, [=]() {
        //选择保存的文件名
        QString path = QFileDialog::getSaveFileName(this, "请选择保存的文件名", "/home/wt/Downloads", "TXT(*.txt*)");
        if (path.isEmpty())
            return;
        //创建文件
        QFile f(path);
        f.open(QIODevice::WriteOnly);
        QString msg = msgEdit->toPlainText();
        f.write(msg.toUtf8().data());
        f.close();
    });
    //清空聊天记录
    connect(clearConversation, &QToolButton::clicked, [=]() {
       msgEdit->clear();
    });
}

//信息相关的操作
void ConversationWindow::socketOperator() {
    socket = new QUdpSocket(this);
    socket->bind(6666, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint);

    //发送消息
    connect(sendBtn, &QPushButton::clicked, [=]() {
        sendMsg(MSGTYPE::MSG);
    });

    //接收消息
    connect(socket, &QUdpSocket::readyRead, [=]() {
        receiveMsg();
    });

    //上线通知
    sendMsg(MSGTYPE::ENTER);
    //下线通知
    connect(exitBtn, &QPushButton::clicked, [=]() {
        //退出窗口
        close();
    });
}

//发送消息
void ConversationWindow::sendMsg(MSGTYPE type) {
    //要发送的消息
    QByteArray data;
    QDataStream out(&data, QIODevice::WriteOnly);
    //先写入消息类型和用户名
    out << type << name;
    if (type == MSGTYPE::MSG) {
        QString msg = sendEdit->toPlainText();
        out << msg;
    }
    //发送消息
    socket->writeDatagram(data, QHostAddress::Broadcast, 6666);
}

//接收消息
void ConversationWindow::receiveMsg() {
    qDebug() << "接收到消息:" << name << endl;
    QByteArray data;
    data.resize(socket->pendingDatagramSize());
    socket->readDatagram(data.data(), data.length());
    QDataStream ds(&data, QIODevice::ReadOnly);
    //读取消息类型
    int type;
    ds >> type;
    //用户名或者信息
    QString name, msg;
    ds >> name;
    //消息时间
    QString time = QDateTime().currentDateTime().toString("yyyy-MM-dd hh:mm:ss");
    //判断消息类型
    switch (type) {
        case MSGTYPE::MSG:
            ds >> msg;
            normalMsg(name, msg, time);
            break;
        case MSGTYPE::ENTER:
            enterMsg(name);
            break;
        case MSGTYPE::EXIT:
            exitMsg(name, time);
            break;
    }
}

//普通消息
void ConversationWindow::normalMsg(QString name, QString msg, QString time) {
    //设置颜色
    msgEdit->setTextColor(Qt::blue);
    msgEdit->append(QString("[%1]%2").arg(name).arg(time));
    msgEdit->append(msg);
    //清空输入框
    sendEdit->clear();
}

//进入消息
void ConversationWindow::enterMsg(QString name) {
    //是否有这个人
    if (tw->findItems(name, Qt::MatchExactly).isEmpty()) {
        //消息显示
        msgEdit->setTextColor(Qt::green);
        msgEdit->append(QString("%1 在线").arg(name));
        //列表显示
        QTableWidgetItem *item = new QTableWidgetItem(name);
        tw->insertRow(0);
        tw->setItem(0, 0, item);

        //更新在线人数
        label->setText(QString("在线人数:%1").arg(tw->rowCount()));

        //发送自己的上线信息给别人
        sendMsg(MSGTYPE::ENTER);
    }
}

//退出消息
void ConversationWindow::exitMsg(QString name, QString time) {
    //是否有这个人
    if (!tw->findItems(name, Qt::MatchExactly).isEmpty()) {
        //消息显示
        msgEdit->setTextColor(Qt::green);
        msgEdit->append(QString("%1 于%2 离开").arg(name).arg(time));
        //列表显示
        int row = tw->findItems(name, Qt::MatchExactly).first()->row();
        tw->removeRow(row);

        //更新在线人数
        label->setText(QString("在线人数:%1").arg(tw->rowCount()));
    }
}

//关闭事件
void ConversationWindow::closeEvent(QCloseEvent *event) {
    //退出
    sendMsg(MSGTYPE::EXIT);
    emit conversationClose();
}