4.9

main.c

#include "widget.h"
#include "newwidget.h"

#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();
    
    Newwidget n;
    
    QObject::connect(&w,&Widget::jump,&n,&Newwidget::showNew);
    QObject::connect(&n,&Newwidget::jump,&w,&Widget::dis);
    
    return a.exec();
}

widget.c

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

#include <QMessageBox>

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
    this->setWindowFlag(Qt::FramelessWindowHint);
    this->setAttribute(Qt::WA_TranslucentBackground);

    // QMessageBox msg;
    // msg.setText("hello");
    // msg.exec();


}

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

void Widget::on_pushButton_clicked()
{
    if(ui->lineEdit->text() == "1" && ui->lineEdit_2->text() == "1")
    {
        QMessageBox msg(QMessageBox::Information,"信息","登录成功",QMessageBox::Yes);
        int ret = msg.exec();

        if(ret == QMessageBox::Yes)
        {
            this->close();
            emit this->jump();
        }
    }
    else
    {
        QMessageBox msg(QMessageBox::Critical,"错误","账号密码错误,是否重新登录",QMessageBox::Yes| QMessageBox::No);
        int ret = msg.exec();
        if(ret == QMessageBox::Yes)
        {
            ui->lineEdit->clear();
            ui->lineEdit_2->clear();
        }
        else if (ret == QMessageBox::No)
        {
            this->close();
        }
    }
}

void Widget::dis()
{
    this->show();
}

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>

QT_BEGIN_NAMESPACE
namespace Ui {
class Widget;
}
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT

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

private slots:
    void on_pushButton_clicked();

public slots:
    void dis();

private:
    Ui::Widget *ui;

signals:
    void jump();
};
#endif // WIDGET_H

newwidget.cpp

#include "newwidget.h"
#include "ui_newwidget.h"
#include <QMessageBox>

Newwidget::Newwidget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Newwidget)
{
    ui->setupUi(this);



}

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

void Newwidget::showNew()
{
    this->show();
}

void Newwidget::on_pushButton_clicked()
{
    QMessageBox msg(QMessageBox::Information,"信息","你是否确定要推出登录",QMessageBox::Yes|QMessageBox::No);
    int ret = msg.exec();
    if(ret == QMessageBox::Yes)
    {
        this->close();
    }
    else if (ret == QMessageBox::No)
    {
        this->close();
        emit this->jump();
    }
}

newwidget.h

#ifndef NEWWIDGET_H
#define NEWWIDGET_H

#include <QWidget>

namespace Ui {
class Newwidget;
}

class Newwidget : public QWidget
{
    Q_OBJECT

public:
    explicit Newwidget(QWidget *parent = nullptr);
    ~Newwidget();

signals:
    void jump();

public slots:
    void showNew();

private slots:
    void on_pushButton_clicked();

private:
    Ui::Newwidget *ui;
};

#endif // NEWWIDGET_H