QT設計秒錶功能(跑步計時器)

#ifndef STOPWATCHWIN_H
#define STOPWATCHWIN_H
 
#include <QMainWindow>
#include <QTime>
#include <QTimer>
namespace Ui {
class StopwatchWin;
}
 
class StopwatchWin : public QMainWindow
{
    Q_OBJECT
 
public:
    explicit StopwatchWin(QWidget *parent = nullptr);
    ~StopwatchWin();
    void fun_clicked();
 
private slots:
    void on_pushButton_clicked();
 
    void on_startBt_clicked();
 
    void on_stopBtn_clicked();
 
    void on_recordBtn_clicked();
 
    void on_resertBt_clicked();
 
private:
    Ui::StopwatchWin *ui;
    //QTime t;
    QTime t = QTime(0,0,0,0);
    QTimer mtimer;
};
 
#endif // STOPWATCHWIN_H

#include "stopwatchwin.h"
#include "ui_stopwatchwin.h"
#include <QDebug>
StopwatchWin::StopwatchWin(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::StopwatchWin)
{
    ui->setupUi(this);
    //把定時器訊號與槽函數關聯
    connect(&mtimer, &QTimer::timeout, this, &StopwatchWin::fun_clicked);
}
 
StopwatchWin::~StopwatchWin()
{
    delete ui;
}
 
void StopwatchWin::fun_clicked()
{
    QString tim = t.toString("hh:mm:ss:zzz");
    t = t.addMSecs(10);
    ui->lcdNumber->display(tim);
    qDebug()<<"1111";
}
void StopwatchWin::on_startBt_clicked()
{
    qDebug()<<"啟動定時器";
    mtimer.start(10);
}
 
void StopwatchWin::on_stopBtn_clicked()
{
    qDebug()<<"停止定時器";
    if(mtimer.isActive())
    {
        mtimer.stop();
    }
}
 
void StopwatchWin::on_pushButton_clicked()
{
 
}
 
void StopwatchWin::on_recordBtn_clicked()
{
    QString tim = t.toString("hh:mm:ss:zzz");
    ui->textBrowser->append(tim);
}
 
void StopwatchWin::on_resertBt_clicked()
{
   t = QTime(0,0,0,0);
}

#include "stopwatchwin.h"
#include <QApplication>
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    StopwatchWin w;
    w.show();
 
    return a.exec();
}