#ifndef FILEWRITE_H
#define FILEWRITE_H

#include <QObject>
#include <QFile>
#include <QString>
#include <QThread>

class FileWrite : public QObject
{
    Q_OBJECT

private:
    class writeThread : public QThread//记得是public继承
    {
    protected:
        void run();
    };
    QFile* m_file;
    writeThread thread;

public:
    explicit FileWrite(QString path, QObject *parent = 0);
    bool fileOpen();
    void fileWrite(const char* text);
    void fileClose();

signals:
    void testWrite(const char* text);
    void testClose();

protected slots:
    void writeSlot(const char* text);
    void closeSlot();


};

#endif // FILEWRITE_H

#include "FileWrite.h"
#include <QIODevice>
#include <QDebug>

FileWrite::FileWrite(QString path, QObject *parent) :
    QObject(parent)
{
    m_file = new QFile(path, this);

    connect(this, SIGNAL(testWrite(const char*)), this, SLOT(writeSlot(const char*)));
    connect(this, SIGNAL(testClose()), this, SLOT(closeSlot()));

    moveToThread(&thread);//这句话极其重要，将槽函数移到线程中执行

    thread.start();
}

bool FileWrite::fileOpen()
{
    return m_file->open(QIODevice::WriteOnly | QIODevice::Text);
}
void FileWrite::fileWrite(const char* text)
{
    emit testWrite(text);
}
void FileWrite::fileClose()
{
    emit testClose();
}
FileWrite::~FileWrite()//析构函数中终止线程执行
{
    thread.quit();
}

/**************************************槽函数******************************************/
void FileWrite::writeSlot(const char* text)
{
    qDebug() << "void FileWrite::writeSlot(const char* text) tid = " << QThread::currentThreadId();

    m_file->write(text);
    m_file->flush();//每次写的时候都直接写入文件，进行低级的IO操作,比较耗时
}
void FileWrite::closeSlot()
{
    qDebug() << "void FileWrite::closeSlot() tid= " << QThread::currentThreadId();

    m_file->close();
}
/***********************************线程的函数*****************************************/
void FileWrite::writeThread::run()
{
    qDebug() << "void FileWrite::writeThread::run() tid= " << QThread::currentThreadId();
    exec();
}

#include <QtCore/QCoreApplication>
#include "FileWrite.h"

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    FileWrite file("C:/Users/LGC/Desktop/test.txt");

    if(file.fileOpen());
    {
        file.fileWrite("Hello word\n");
        file.fileWrite("你好，世界\n");
        file.fileWrite("狄泰软件学院,成就梦想\n");
        file.fileClose();
    }
    
    return a.exec();
}