Qt多线程实现思路二

 1 #ifndef MYTHREAD_H
 2 #define MYTHREAD_H
 3 #include <QThread>
 4 
 5 class myThread : public QObject
 6 {
 7     Q_OBJECT
 8 public:
 9     explicit myThread(QObject *parent = 0);
10     //线程处理函数
11     void myTimeout();
12 
13     void setFlag(bool flag = true);
14 
15 signals:
16     void mySignal();
17 
18 public slots:
19 
20 private:
21     bool isStop;
22 };
23 
24 #endif // MYTHREAD_H

 1 #include "mythread.h"
 2 #include <QThread>
 3 #include <QDebug>
 4 
 5 
 6 myThread::myThread(QObject *parent) : QObject(parent)
 7 {
 8     isStop = false;
 9 }
10 
11 void myThread::myTimeout()
12 {
13     while( !isStop )
14     {
15 
16         QThread::sleep(1);
17         emit mySignal();
18 
19 
20          qDebug() << "子线程号：" << QThread::currentThread();
21 
22          if(isStop)
23          {
24              break;
25          }
26     }
27 }
28 
29 void myThread::setFlag(bool flag)
30 {
31     isStop = flag;
32 }

 1 #ifndef WIDGET_H
 2 #define WIDGET_H
 3 #include "mythread.h"
 4 #include <QWidget>
 5 #include <QTimer>
 6 #include <QThread>
 7 #include <QDebug>
 8 namespace Ui {
 9 class Widget;
10 }
11 
12 class Widget : public QWidget
13 {
14     Q_OBJECT
15 
16 public:
17     explicit Widget(QWidget *parent = 0);
18     ~Widget();
19     void dealSignal();
20     void dealClose();
21 
22 signals:
23     void startThread(); //启动子线程的信号
24 
25 private slots:
26 
27     void on_start_clicked();
28 
29     void on_stop_clicked();
30 
31 private:
32     Ui::Widget *ui;
33     myThread *myT;
34     QThread *thread;
35 };
36 
37 #endif // WIDGET_H

 1 #include "widget.h"
 2 #include "ui_widget.h"
 3 #include "mythread.h"
 4 Widget::Widget(QWidget *parent) :
 5     QWidget(parent),
 6     ui(new Ui::Widget)
 7 {
 8     ui->setupUi(this);
 9     myT = new myThread;//不能初始化指定父类myThread(this)
10 
11     //创建子线程
12     thread = new QThread(this);
13 
14     //把自定义线程加入到子线程中
15     myT->moveToThread(thread);
16 
17     connect(myT, &myThread::mySignal, this, &Widget::dealSignal);
18 
19     qDebug() << "主线程号：" << QThread::currentThread();
20 
21     connect(this, &Widget::startThread, myT, &myThread::myTimeout);
22 
23     //窗口关闭时调用线程关闭，前提是线程要运行完当前任务
24     connect(this, &Widget::destroyed, this, &Widget::dealClose);
25  
30 }
31 
32 Widget::~Widget()
33 {
34     delete ui;
35 }
36 
37 void Widget::dealClose()
38 {
39     on_stop_clicked();
40     delete myT;
41 }
42 
43 void Widget::dealSignal()
44 {
45     static int i = 0;
46     i++;
47     ui->lcdNumber->display(i);
48 }
49 
50 void Widget::on_start_clicked()
51 {
52     if(thread->isRunning() == true)
53     {
54         return;
55     }
56 
57     //启动线程，但是没有启动线程处理函数
58     thread->start();
59     myT->setFlag(false);
60 
61     //不能直接调用线程处理函数，
62     //直接调用，导致，线程处理函数和主线程是在同一个线程
63     //只能通过 signal - slot 方式调用
64     emit startThread();
65 }
66 
67 void Widget::on_stop_clicked()
68 {
69     if(thread->isRunning() == false)
70     {
71         return;
72     }
73 
74     myT->setFlag(true);
75     thread->quit();
76     thread->wait();
77 }