一、思维导图

二、练习

#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_login_btn_clicked()
{
    if(ui->id_edit->text() == "kkk" && ui->passwd_edit->text() == "123456")
    {
        QMessageBox::information(this,"info","登录成功",QMessageBox::Yes);
        this->close();
    }
    else
    {
        int ret = QMessageBox::critical(this,"wrong","账号密码错误，是否重新登陆？",QMessageBox::Yes | QMessageBox::No);
        if(ret == QMessageBox::Yes)
        {
            ui->passwd_edit->clear();
            ui->id_edit->clear();
        }
        else if(ret == QMessageBox::No)
        {
            this->close();
        }
    }
}

void Widget::on_exit_btn_clicked()
{
    int ret = QMessageBox::question(this, "question", "是否确定退出登录？", QMessageBox::Yes | QMessageBox::No);
        if(ret == QMessageBox::Yes)
        {
            close();
        }
}