Qt学习: QTimerEvent定时器事件的处理程序代码示例

重要函数:
1.int startTimer(int); //设置定时器，返回一个ld.
2.int event->timerld(); //返回当前的ld.
3.void killTimer(int); //停止定时器.

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首先从Qt设计师中拖拽出三个按钮，由于只是演示定时器事件的使用，所以就没有布局的需要了.

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以下是”c.cpp”的代码:

#include "c.h"

c::c(QWidget *parent)
    : QMainWindow(parent)
{
    ui.setupUi(this);


    //连接信号与槽.
    connect(ui.startButton, SIGNAL(clicked()), this, SLOT(startTimerSlot()));
    connect(ui.stopButton, SIGNAL(clicked()), this, SLOT(stopTimerSlot()));
}

c::~c()
{

}
void c::timerEvent(QTimerEvent*event)
{
    //判断当前定时器对应的是哪个ld.
    if (event->timerId() == this->m_lamp)
    {
        if (this->m_lampStatus == false)
        {
            //设置按钮的图标.
            ui.toolButton->setIcon(QIcon("Icons/lamp.png"));
            this->m_lampStatus = true;
        }
        else
        {
            ui.toolButton->setIcon(QIcon("Icons/space.png")); 
            this->m_lampStatus = false;
        }
    }
}
void c::startTimerSlot()
{
    //设置定时器，返回一个timerld.注意单位为毫秒，1000毫秒等于1秒.
    this->m_lamp = this->startTimer(1000);
}
void c::stopTimerSlot()
{
    //停止定时器.
    this->killTimer(this->m_lamp);
}

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以下是”c.h”的代码:

#ifndef C_H
#define C_H

#include <QtWidgets/QMainWindow>
#include "ui_c.h"
#include <QLabel>
#include <QTimerEvent>


class c : public QMainWindow
{
    Q_OBJECT

public:
    c(QWidget *parent = 0);
    ~c();
protected:
    //这是一个虚函数，从QEvent继承而来.
    void timerEvent(QTimerEvent*event);
private slots:
    void startTimerSlot();
    void stopTimerSlot();

private:
    Ui::cClass ui;
    int m_lamp;
    bool m_lampStatus = false;
};

#endif // C_H

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最后是”main.cpp”的代码:

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

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