Qt5线程之间通信的小例子

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include<QString>
namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();
public slots:
    void hasRead(QString);
private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include"myreader.h"
#include<qthread.h>
#include<QDebug>
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    qDebug()<<"Main Thread`s id:"<<this->thread()->currentThreadId();
    //============
    MyReader * reader=new MyReader();
    QThread * t=new QThread();
    reader->moveToThread(t);
    //|注意新线程需要开启 start 否则不能使用！！
    t->start();
    QObject::connect(this->ui->pushButton,SIGNAL(clicked()),reader,SLOT(reading()));
    QObject::connect(reader,SIGNAL(hasread(QString)),this,SLOT(hasRead(QString)));
}

MainWindow::~MainWindow()
{
    delete ui;
}
void MainWindow::hasRead(QString s)
{
    qDebug()<<"MainWindow::hasRead`s Thread id:"<<this->thread()->currentThreadId();
    this->ui->textBrowser->append(s);
}

myreader.h

#ifndef MYREADER_H
#define MYREADER_H
#include<QObject>
#include<QString>
class MyReader:public QObject
{
    Q_OBJECT
public:
    MyReader();
    ~MyReader();
signals:
    void hasread(QString);
 public slots:
    void reading();
};

#endif // MYREADER_H

myreader.cpp

#include "myreader.h"
#include<QDebug>
#include<qthread.h>
#include<QFile>
MyReader::MyReader()
{

}

MyReader::~MyReader()
{

}
void MyReader::reading()
{
    qDebug()<<"MyReader`s Thread id :"<<this->thread()->currentThreadId();
    QFile f("E:/1.txt");
    f.open(QIODevice::ReadOnly);
    QString data=f.readAll();
    emit hasread(data);
}

main.cpp

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

运行结果：

qDebug()输出结果：

Main Thread`s id: 0x1d3c
MyReader`s Thread id : 0x2260
MainWindow::hasRead`s Thread id: 0x1d3c
MyReader`s Thread id : 0x2260
MainWindow::hasRead`s Thread id: 0x1d3c

线程之间只能采用 信号、槽的 方式进行通信~