QT子线程发射信号，UI接收信号刷新UI

#include <QtGui>  
#include <QtCore> 
#include <windows.h>


class Thread : public QThread  
{  
Q_OBJECT  
private:  
int number;  
protected:  
void run();  
public:  
Thread(QObject *parent=0);  
~Thread();  
signals:  
void UpdateSignal(int num);  
public slots:  
void ResetSlot();  
};  


class Widget : public QWidget  
{  
Q_OBJECT  
private:  
QLabel *label;  
QPushButton *startButton;  
QPushButton *stopButton;  
QPushButton *resetButton;  
Thread *myThread;  
int number;  
public:  
Widget(QWidget *parent = 0);  
~Widget();  
signals:  
void ResetSignal();  
public slots:  
void ClearSlot();  
void StartSlot();  
void StopSlot();  
void UpdateSlot(int num);  
};  


Thread::Thread(QObject *parent)  
{  
number = 0;  
}  


Thread::~Thread()  
{  


}  


void Thread::run()  
{  
while(1)  
{  
//开启一个死循环，让number每秒自增1，并通过发送UpdateSignal信号通知主界面更新
emit UpdateSignal(number);  
number++;  
sleep(1);  
}  
}  


void Thread::ResetSlot()  
{  
number = 0;  
emit UpdateSignal(number);  
}  


Widget::Widget(QWidget *parent)  
{  
//设置界面布局
startButton = new QPushButton("start");  
stopButton = new QPushButton("stop");  
resetButton = new QPushButton("reset");  
label = new QLabel("empty");  
myThread = new Thread;  
QVBoxLayout *layout = new QVBoxLayout;  
layout->addWidget(label);  
layout->addWidget(startButton);  
layout->addWidget(stopButton);  
layout->addWidget(resetButton);  
setLayout(layout);  


//连接各自信号糟
connect(stopButton, SIGNAL(clicked()),   
this, SLOT(StopSlot()));  
connect(startButton, SIGNAL(clicked()),  
this, SLOT(StartSlot()));  
connect(resetButton, SIGNAL(clicked()),  
this, SLOT(ClearSlot()));  
connect(myThread, SIGNAL(UpdateSignal(int)),   
this, SLOT(UpdateSlot(int)));  
connect(this, SIGNAL(ResetSignal()),  
myThread, SLOT(ResetSlot()));  




setWindowTitle("Thread Test");  
resize(200, 200);  
myThread->start();  


}  


Widget::~Widget()  
{  


}  


void Widget::StartSlot()  
{  
myThread->start();  
}  


void Widget::StopSlot()  
{  
myThread->terminate();  
}  


void Widget::UpdateSlot(int num)  
{  
label->setText(QString::number(num));  
}  


void Widget::ClearSlot()  
{  
emit ResetSignal();  
}  


#include "main.moc"


int main(int argc, char **argv)  
{  
QApplication app(argc, argv);  
Widget *widget = new Widget;  
widget->show();  
return app.exec();  
}