作业1：

mywidget.h

#ifndef MYWIDGET_H
#define MYWIDGET_H

#include <QWidget>
#include <QLabel>
#include <QMessageBox>

QT_BEGIN_NAMESPACE
namespace Ui { class myWidget; }
QT_END_NAMESPACE

class myWidget : public QWidget
{
    Q_OBJECT

public:
    myWidget(QWidget *parent = nullptr);
    ~myWidget();

signals:
void myjump();

public slots:
    void play();

private slots:
    void on_pushButton_2_clicked();
    void on_pushButton_3_clicked();
    void on_pushButton_4_clicked();

private:
    Ui::myWidget *ui;
};
#endif // MYWIDGET_H

main.cpp

#include "mywidget.h"
#include "second.h"

#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    myWidget w;
    second s;
    w.show();
    QObject::connect(&w,&myWidget::myjump,&s,&second::myslot);
    return a.exec();
}

mywidget.cpp

#include "mywidget.h"
#include "ui_mywidget.h"

myWidget::myWidget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::myWidget)
{
    ui->setupUi(this);
    this->setWindowFlag(Qt::FramelessWindowHint);
    ui->lineEdit->setPlaceholderText("手机号/QQ号");
    ui->lineEdit_1->setEchoMode(QLineEdit::Password);
    connect(ui->pushButton,&QPushButton::clicked,this,&myWidget::play);
}

//实现点击登录后的相关功能
void myWidget::play()
{
    QString text1=ui->lineEdit->text();
    QString text2=ui->lineEdit_1->text();
    if(text1=="666" && text2=="123456")
    {
        QMessageBox::information(this,"提示","登录成功",QMessageBox::Ok);
        this->close();
        emit myjump();
    }
    else
    {
        QMessageBox::StandardButton res=QMessageBox::critical(this,"错误","账号和密码不匹配，是否重新登录",QMessageBox::Yes|QMessageBox::No);
        if(res==QMessageBox::Yes)
        {
            ui->lineEdit_1->setText("");
        }
        else
        {
          this->close();
        }
    }
}
myWidget::~myWidget()
{
    delete ui;
}

//实现点击取消后的相关功能
void myWidget::on_pushButton_2_clicked()
{
   this->showMinimized();
}

void myWidget::on_pushButton_3_clicked()
{
    this->close();
}

void myWidget::on_pushButton_4_clicked()
{
    QMessageBox::StandardButton res=QMessageBox::question(this,"问题","您是否确定要退出登录？",QMessageBox::Yes|QMessageBox::No);
    if(res==QMessageBox::Yes)
    {
        this->close();
    }
}

作业2：

mywidget.h

#ifndef MYWIDGET_H
#define MYWIDGET_H

#include <QWidget>
#include <QTimerEvent>
#include <QTime>
#include <QDebug>
#include <QTextToSpeech>

QT_BEGIN_NAMESPACE
namespace Ui { class myWidget; }
QT_END_NAMESPACE

class myWidget : public QWidget
{
    Q_OBJECT

public:
    myWidget(QWidget *parent = nullptr);
    ~myWidget();
    void timerEvent(QTimerEvent* E);

private slots:
    void on_pushButton_clicked();

    void on_pushButton_2_clicked();

private:
    Ui::myWidget *ui;
    int id;
};
#endif // MYWIDGET_H

mywidget.cpp

#include "mywidget.h"
#include "ui_mywidget.h"

myWidget::myWidget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::myWidget)
{
    ui->setupUi(this);
    this->setWindowTitle("闹钟");
}

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

void myWidget::timerEvent(QTimerEvent *E)
{
    if(E->timerId()==id)
    {
        QTime time1=QTime::currentTime();
        QString t=time1.toString(("hh:mm:ss"));
        ui->label->setText(t);
        ui->label->setAlignment(Qt::AlignCenter);
        if(ui->label->text()==ui->lineEdit->text())
        {
            ui->label_3->setText("懒虫起床了! 懒虫起床了!");
            QTextToSpeech* speech=new QTextToSpeech(this);
            speech->say("懒虫起床了! 懒虫起床了!");
        }
    }
}

void myWidget::on_pushButton_clicked()
{
    QString fel=ui->lineEdit->text();
}

void myWidget::on_pushButton_2_clicked()
{
    QString fel=ui->pushButton_2->text();
    if(fel=="打开")
    {
        id=startTimer(1000);
        ui->pushButton_2->setText("关闭");
    }
    else
    {
        killTimer(id);
        ui->pushButton_2->setText("打开");
    }
}