這個例子是在參考教材略微改了一下。

     主要實現的是單擊開始按鈕啟動數個工作執行緒，工作執行緒數目由一個巨集定義的常數決定，各個執行緒迴圈列印數字0~9,直到按下停止按鈕，終止所有執行緒。

新建QtGUi專案我的專案叫threaddlg，在ui Designer裡設定按鈕以及名稱。

新增類命名為workthread,專案檔案如下：

在threaddlg.h中程式碼如下：

#pragma once

#include <QtWidgets/QDialog>
#include "ui_threaddlg.h"
#include "workthread.h"
#include <QMessageBox>

#define MAXSIZE 5

class threaddlg : public QDialog
{
	Q_OBJECT

public:
	threaddlg(QWidget *parent = Q_NULLPTR);
public slots:
    void BtnStartClicked();
	void BtnStopClicked();

private:
	Ui::threaddlgClass ui;
	workthread *workThread[MAXSIZE];
};
 

threaddlg.cpp中的程式碼如下：

#include "threaddlg.h"

threaddlg::threaddlg(QWidget *parent)
	: QDialog(parent)
{
	ui.setupUi(this);
	connect(ui.BtnStart, SIGNAL(clicked()), this, SLOT(BtnStartClicked()));
	connect(ui.Btnstop, SIGNAL(clicked()), this, SLOT(BtnStopClicked()));
	connect(ui.BtnQuit, SIGNAL(clicked()), this, SLOT(close()));
}
void threaddlg::BtnStartClicked()
{
	QMessageBox::information(this, "OK", "Connect Successful");
	for (int i = 0; i < MAXSIZE; i++)
	{
		workThread[i] = new workthread();
	}
	for (int i = 0; i < MAXSIZE; i++)
	{
		workThread[i]->start();
	}
	ui.BtnStart->setEnabled(false);
	ui.Btnstop->setEnabled(true);
}
void threaddlg::BtnStopClicked()
{
	QMessageBox::information(this, "OK", "Connect Successful");
	for (int i = 0; i < MAXSIZE; i++)
	{
		workThread[i]->terminate();
		workThread[i]->wait();
	}
	ui.BtnStart->setEnabled(true);
	ui.Btnstop->setEnabled(false);
}
 

workthread.h程式碼如下：

#pragma once
#include <QThread>
#include <QDebug>

class workthread:public QThread
{
public:
	workthread();
	~workthread();
protected:
	void run();
};

workthread.cpp程式碼為

#include "workthread.h"



workthread::workthread()
{
}


workthread::~workthread()
{
}
void workthread::run()
{
	while (true)
	{
		for (int n = 0; n < 10; n++)
			qDebug() << n << n << n << n << n << n << n << n;
	}
}
 

main.cpp程式碼為

#include "threaddlg.h"
#include <QtWidgets/QApplication>

int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	threaddlg w;
	w.show();
	return a.exec();
}

輸出視窗放大：