1.制作闹钟

头文件

#include <QWidget>
#include <QTimerEvent>
#include <QTime>
#include <QtTextToSpeech/QTextToSpeech>
#include <QTextEdit>
#include <QString>QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACEclass Widget : public QWidget
{Q_OBJECTpublic:Widget(QWidget *parent = nullptr);~Widget();void timerEvent(QTimerEvent *e) override;       //定时器事件处理函数private slots:void on_startBtn_clicked();void on_stopBtn_clicked();private:Ui::Widget *ui;QTextToSpeech *speecher;int timer_id;
};
#endif // WIDGET_H

源函数

#include "widget.h"
#include "ui_widget.h"Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);speecher = new QTextToSpeech(this);
}Widget::~Widget()
{delete ui;
}//开始按钮对应的槽函数
void Widget::on_startBtn_clicked()
{timer_id = this->startTimer(1000);
}//停止按钮
void Widget::on_stopBtn_clicked()
{//this->killTimer(timer_id);speecher->stop();ui->lineEdit->clear();
}void Widget::timerEvent(QTimerEvent *e){if(e->timerId() == timer_id){QTime sys_t = QTime::currentTime();    //获取系统时间QString t = sys_t.toString("hh:mm:ss");    //将QTime类对象转换为字符串ui->nowtimeLeb->setText(t);        //展示到ui界面if(t == ui->lineEdit->text()){speecher->say(ui->textEdit->toPlainText());}}}

主函数

#include "widget.h"#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);Widget w;w.show();return a.exec();
}

2.保存文件

头文件

#ifndef WIDGET_H
#define WIDGET_H#include <QWidget>
#include <QFileDialog>
#include <QFile>
#include <QMessageBox>QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACEclass Widget : public QWidget
{Q_OBJECTpublic:Widget(QWidget *parent = nullptr);~Widget();private slots:void on_pushButton_clicked();private:Ui::Widget *ui;
};
#endif // WIDGET_H

源文件

#include "widget.h"
#include "ui_widget.h"Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);
}Widget::~Widget()
{delete ui;
}void Widget::on_pushButton_clicked()
{QString fileName =  QFileDialog::getSaveFileName(this,"保存文件","./","Text file(*.txt)");if(fileName.isNull()){QMessageBox::information(this, "提示", "用户取消了保存文件");return ;}QFile file(fileName);if(!file.isOpen()){if(!file.open(QFile::ReadWrite)){QMessageBox::critical(this, "失败", "文件打开失败");return;}}QString msg = ui->textEdit->toPlainText();file.write(msg.toUtf8());file.close();
}

主函数

#include "widget.h"#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);Widget w;w.show();return a.exec();
}