一步一步来吧,不可能一口吃成一个胖子.

看不懂大块的代码,至少可以看懂一个小demo,一小部分代码,小demo看的多了,慢慢也就可以看懂更多代码啦.加油!

不要着急啦!

QLocalServer和QLocalSocket单进程和进程通信 - wjbooks - 博客园 (cnblogs.com)

QLocalSocket 

1.生成随机数

 QT qrand()随机函数-CSDN博客

qsrand(QTime(0,0,0).secsTo(QTime::currentTime()));
int num=qrand();

 2.QLocalSocket类连接到本地服务器"localserver-test"

    QLocalSocket ls;
    ls.connectToServer("localserver-test");

3.等待连接到服务器,如果不可以,返回false

ls.waitForConnected()

4.一直循环,向服务器发送随机数(每隔一秒).

        while (1){
            QTextStream ts(&ls);
            ts << QString::number(qrand()) + "\nTTTTTTTTTT" + "\nXXXXXXXX";
            ts.flush();
            ls.waitForBytesWritten();
            sleep(1);
        }

QLocalServer

本地服务器,用于本地的进程间通讯

#ifndef SERVER_H
#define SERVER_H
#include <QLocalServer>
#include <QLocalSocket>
class Server : public QObject
{
    Q_OBJECT
public:
    Server()
    {
        m_server = 0;
    }
    ~Server()
    {
        if (m_server)
        {
            delete m_server;
        }
    }
    int init(const QString & servername)
    {
        // 如果已经有一个实例在运行了就返回0
        if (isServerRun(servername)) {
            return 0;
        }
        m_server = new QLocalServer;
        // 先移除原来存在的,如果不移除那么如果
        // servername已经存在就会listen失败
        QLocalServer::removeServer(servername);
        // 进行监听
        m_server->listen(servername);
        connect(m_server, SIGNAL(newConnection()), this, SLOT(newConnection()));
        return 1;
    }
private slots:
    // 有新的连接来了
    void newConnection()
    {
        QLocalSocket *newsocket = m_server->nextPendingConnection();
        connect(newsocket, SIGNAL(readyRead()), this, SLOT(readyRead()));
    }
    // 可以读数据了
    void readyRead()
    {
        // 取得是哪个localsocket可以读数据了
        QLocalSocket *local = static_cast<QLocalSocket *>(sender());
        if (!local)
            return;
        QTextStream in(local);
        QString     readMsg;
        // 读出数据
        readMsg = in.readAll();
        // 发送收到数据信号
        emit newMessage(readMsg);
    }
private:
    // 判断是否有一个同名的服务器在运行
    int isServerRun(const QString & servername)
    {
        // 用一个localsocket去连一下,如果能连上就说明
        // 有一个在运行了
        QLocalSocket ls;
        ls.connectToServer(servername);
        if (ls.waitForConnected(1000)){
            // 说明已经在运行了
            ls.disconnectFromServer();
            ls.close();
            return 1;
        }
        return 0;
    }
signals:
    void newMessage(const QString &msg);
private:
    QLocalServer *m_server;
};
#endif // SERVER_H

#include <QApplication>
#include <QLabel>
#include <QMessageBox>
#include "widget.h"
int main(int argc, char **argv)
{
    QApplication app(argc, argv);
    QLabel       text("teststts");
    Server       s;
    if (!s.init("localserver-test")){
        // 初使化失败, 说明已经有一个在运行了
        QMessageBox::information(&text, "info", "There is already exist one!");
        return 1;
    }
    QObject::connect(&s, SIGNAL(newMessage(const QString &)),&text, SLOT(setText(const QString &)));
    text.show();
    return app.exec();
}

效果: