thread

 1 //mythread.cpp
 2 
 3 #include "mythread.h"
 4 
 5 MyThread::MyThread(QObject *parent) : QThread(parent)
 6 {
 7 
 8 }
 9 
10 void MyThread::run()
11 {
12     //很复杂的数据处理
13     //需要耗时5s
14     sleep(5);
15     emit isDone();
16 }

//mythread.h

#ifndef MYTHREAD_H
#define MYTHREAD_H

#include <QThread>
class MyThread : public QThread
{
    Q_OBJECT
public:
    explicit MyThread(QObject *parent = 0);
protected:
    void run();
signals:
    void isDone();
public slots:
};

#endif // MYTHREAD_H

//mywidget.cpp

#include "mywidget.h"
#include "ui_mywidget.h"
#include <QThread>
#include <QDebug>

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

    myTimer = new QTimer(this);
    connect(myTimer, &QTimer::timeout, this, &MyWidget::dealTimeout);

    //分配空间
    thread = new MyThread(this);
    connect(thread, &MyThread::isDone, this, &MyWidget::dealDone);

    //当按窗口右上角x时，窗口触发destroyed()
    connect(this, &MyWidget::destroyed, this, &MyWidget::stopThread)
}

void MyWidget::stopThread()
{
    //停止线程
    thread->quit();
    //等待线程处理完手头动作
    thread->wait();
}

void MyWidget::dealDone()
{
    qDebug() << "it is over";
    myTimer->stop(); //关闭定时器
}

void MyWidget::dealTimeout()
{
    static int i = 0;
    i++;
    //设置lcd的值
    ui->lcdNumber->display(i);
}

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

void MyWidget::on_pushButton_clicked()
{
    //如果定时器没有工作
    if(myTimer->isActive() == false)
    {
        myTimer->start(100);
    }
    //启动线程，处理数据
    thread->start();
}

#ifndef MYWIDGET_H
#define MYWIDGET_H

#include <QWidget>
#include <QTimer> //定时器头文件
#include "mythread.h" //线程头文件

namespace Ui {
class MyWidget;
}

class MyWidget : public QWidget
{
    Q_OBJECT

public:
    explicit MyWidget(QWidget *parent = 0);
    ~MyWidget();

    void dealTimeout(); //定时器槽函数
    void dealDone(); //线程结束槽函数
    void stopThread(); //停止线程槽函数

private slots:
    void on_pushButton_clicked();

private:
    Ui::MyWidget *ui;
    QTimer *myTimer; //声明变量
    MyThread *thread; //线程对象
};

#endif // MYWIDGET_H