.pro

#-------------------------------------------------
#
# Project created by QtCreator 2016-05-30T22:59:31
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = mytimerevent
TEMPLATE = app


SOURCES += main.cpp\
        widget.cpp

HEADERS  += widget.h

FORMS    += widget.ui

main.cpp

#include "widget.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();

    return a.exec();
}

widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include <QDebug>
#include <QTimer>
#include <QTime>

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

    id1 = startTimer(1000);                  // 开启一个1秒定时器，返回其ID
    id2 = startTimer(1500);
    id3 = startTimer(2200);

    QTimer *timer = new QTimer(this);           // 创建一个新的定时器
    // 关联定时器的溢出信号到槽上
    connect(timer, &QTimer::timeout, this, &Widget::timerUpdate);
    timer->start(1000);                         // 设置溢出时间为1秒，并启动定时器

    qsrand(QTime(0, 0, 0).secsTo(QTime::currentTime()));

    QTimer::singleShot(10000, this, &Widget::close);
}

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


void Widget::timerEvent(QTimerEvent *event)
{
    if (event->timerId() == id1) {       // 判断是哪个定时器
        qDebug() << "timer1";
    }
    else if (event->timerId() == id2) {
        qDebug() << "timer2";
    }
    else {
        qDebug() << "timer3";
    }
}

void Widget::timerUpdate()                  // 定时器溢出处理
{
    QTime time = QTime::currentTime();      // 获取当前时间
    QString text = time.toString("hh:mm");  // 转换为字符串
    if((time.second() % 2) == 0) text[2]=' '; // 每隔一秒就将“：”显示为空格
    ui->lcdNumber->display(text);

    int rand = qrand() % 300;            // 产生300以内的正整数
    ui->lcdNumber->move(rand, rand);

}

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>

namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT

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

private:
    Ui::Widget *ui;
    int id1, id2, id3;

protected:
    void timerEvent(QTimerEvent *event);

private slots:
    void timerUpdate();


};

#endif // WIDGET_H