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Introduction to Qt (4) - Continuous playback of pictures (the use of two timers)

2022-08-08 23:07:00 【light chases rain】

文章目录

一、QObject
二、QTimer

一、QObject

1.1 ui设计

1.1.1 图像成果

在这里插入图片描述

1.1.2 类名定义

在这里插入图片描述

1.2 代码展示

1.2.1 widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include <QPixmap>
#define TIMEOUT 1000

namespace Ui {
    
class Widget;
}

class Widget : public QWidget
{
    
    Q_OBJECT

public:
    explicit Widget(QWidget *parent = 0);
    void timerEvent(QTimerEvent *e);
    ~Widget();

private slots:
    void on_StartButton_clicked();


    void on_StopButton_clicked();

private:
    Ui::Widget *ui;
    int timerId;
    int PicId;
};

#endif // WIDGET_H

1.2.2 main.cpp

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

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

    return a.exec();
}

1.2.3 widget.cpp

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    
    ui->setupUi(this);
    PicId = 2;
    QPixmap pix("C:/Users/DELL/Desktop/pic_while/img/1.jpg");
    ui->Showlabel->setPixmap(pix);
}

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

void Widget::timerEvent(QTimerEvent *e)
{
    
    if(e->timerId() != timerId)
    {
    
        return;
    }
    QString Path("C:/Users/DELL/Desktop/pic_while/img/");
    Path += QString::number(PicId);
    Path += ".jpg";
    QPixmap pix(Path);
    ui->Showlabel->setPixmap(pix);
    PicId++;
    if(PicId == 7)
    {
    
        PicId = 1;
    }
}


void Widget::on_StartButton_clicked()
{
    
    timerId = this->startTimer(TIMEOUT);
}


void Widget::on_StopButton_clicked()
{
    
    this->killTimer(timerId);
}

1.3 成果展示

请添加图片描述

二、QTimer

2.1 ui设计

2.1.1 图像成果

在这里插入图片描述

2.1.2 类名定义

在这里插入图片描述

2.2 代码展示

2.2.1 widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include <QTimer>
#define TIMEOUT 1000

namespace Ui {
    
class Widget;
}

class Widget : public QWidget
{
    
    Q_OBJECT

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

private slots:
    void on_StartButton_clicked();
    void TimeoutSlots();

    void on_pushButton_3_clicked();

    void on_OnceButton_clicked();

private:
    Ui::Widget *ui;
    QTimer *timer;
    int PicId;
};

#endif // WIDGET_H

2.2.2 main.cpp

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

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

    return a.exec();
}

2.2.3 widget.cpp

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    
    timer = new QTimer;
    PicId = 2;
    ui->setupUi(this);
    ui->mainlabel->setPixmap(QPixmap::fromImage(QImage("C:/Users/DELL/Desktop/QTimer/img/1.jpg")));
    connect(timer,&QTimer::timeout,this,&Widget::TimeoutSlots);
}

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

void Widget::on_StartButton_clicked()
{
    
    timer->start(TIMEOUT);
}

void Widget::TimeoutSlots()
{
    
    QString Path("C:/Users/DELL/Desktop/QTimer/img/");
    Path += QString::number(PicId);
    Path += ".jpg";
    ui->mainlabel->setPixmap(QPixmap::fromImage(QImage(Path)));
    PicId++;
    if(PicId == 7)
    {
    
        PicId = 1;
    }
}

void Widget::on_pushButton_3_clicked()
{
    
    timer->stop();
}

void Widget::on_OnceButton_clicked()
{
    
    QTimer::singleShot(20,this,SLOT(TimeoutSlots()));
}