QT: 用定时器完成闹钟的实现

闹钟项目：

widget.h

#ifndef WIDGET_H
#define WIDGET_H#include <QWidget>
#include <QTimerEvent>
#include <QTime>
#include <QDebug>
#include <QTextToSpeech>
#include <QMessageBox>
#include <QTimer>QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACEclass Widget : public QWidget
{Q_OBJECTpublic:Widget(QWidget *parent = nullptr);~Widget();void timerEvent(QTimerEvent *e);   //要重写的关于定时器时间处理函数的声明private slots:void on_startBtn_clicked();void on_stopBtn_clicked();private:Ui::Widget *ui;QTextToSpeech *speecher;QTimer *timer;int tId;
};
#endif // WIDGET_H

widget.cpp

#include "widget.h"
#include "ui_widget.h"Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);ui->hangEdit->setText("20-20-20");tId = startTimer(1000);this->timer = new QTimer;speecher = new QTextToSpeech(this);}Widget::~Widget()
{delete ui;}void Widget::timerEvent(QTimerEvent *e)
{if(e->timerId()==tId){//获取系统时间QTime sys_time = QTime::currentTime();    //QTime类对象//将时间转化为字符串QString t = sys_time.toString("hh-mm-ss");//将字符串展示到ui界面ui->syslabel->setText(t);ui->syslabel->setAlignment(Qt::AlignCenter);if(ui->syslabel->text()==ui->hangEdit->text()){speecher->say(ui->tEdit->toPlainText());}}
}void Widget::on_startBtn_clicked()
{if(ui->hangEdit->text()== NULL){QMessageBox::critical(this,"错误","请先编辑时间",QMessageBox::Ok);}return;timer->start(100);ui->hangEdit->setReadOnly(true);ui->tEdit->setReadOnly(true);}void Widget::on_stopBtn_clicked()
{int ret  =   QMessageBox::question(this,"提示","确定要停止闹钟吗？",QMessageBox::Yes | QMessageBox::No);if(ret = QMessageBox::Yes){timer->stop();ui->hangEdit->setReadOnly(false);ui->tEdit->setReadOnly(false);ui->hangEdit->clear();}}

思维导图：