#ifndef WIDGET_H
#define WIDGET_H#include <QWidget>QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACEclass Widget : public QWidget
{Q_OBJECTpublic:Widget(QWidget *parent = nullptr);// 需要对timerEvent函数进行重写virtual void timerEvent(QTimerEvent* event);~Widget();private slots:void on_startTimer_clicked();void on_killTimer_clicked();private:Ui::Widget *ui;int eventId; // 定时器返回的唯一id，用于区分不同定时器int pictureId=1; // 不同图片的编号
};
#endif // WIDGET_H#include "widget.h"
#include "ui_widget.h"#define TIME_OUT 1 * 1000/**
QObject中有定时器，可以直接进行使用startTimer和killTimer操作
但需要对timerEvent进行重新定义，以自己的方式处理定时器
*/
Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);QString path("D:\\workspace\\qt\\Timer\\");path += QString::number(this->pictureId)+".jpg";QPixmap pix(path);ui->label->setPixmap(pix);
}Widget::~Widget()
{delete ui;
}void Widget::on_startTimer_clicked()
{// 开启定时器// QObject中有定时器，直接使用，Widget->QWidget->QObjectthis->eventId = this->startTimer(TIME_OUT);}void Widget::timerEvent(QTimerEvent* event) {// 获取timerId是否为开启定时器所操作的if (event->timerId() == this->eventId) {QString path("D:\\workspace\\qt\\Timer\\");path += QString::number(this->pictureId)+".jpg";QPixmap pix(path);ui->label->setPixmap(pix);this->pictureId++;if (this->pictureId == 5) {this->pictureId = 1;}}
}void Widget::on_killTimer_clicked()
{this->killTimer(this->eventId);
}