QT项目：仿有道云的笔记管理系统（一）—— Login界面实现

Login界面

涉及知识点

1. 隐藏标题栏

   this->setWindowFlags(Qt::FramelessWindowHint);

2. 自定义最小化按钮和关闭按钮

   void login::on_bt_close_clicked()
   {
       this->close();
   }
   
   void login::on_bt_min_clicked()
   {
       if( windowState() != Qt::WindowMinimized )
       {
           setWindowState( Qt::WindowMinimized );
       }
   }

3. LineEdit设为密码模式

   ui->edit_password->setEchoMode(QLineEdit::Password);

4. 登录用户名密码检测

   void login::on_bt_login_clicked()
   {
       QString username=ui->edit_account->text();
       QString password=ui->edit_password->text();
   
       QString sql="select * from accountDB where username='"+username+"'";
       QSqlQuery query;
   
       query.exec(sql);
       while(query.next())
       {
           QString passwordQuery=query.value(3).toString();
           cout<<passwordQuery.toStdString()<<endl;
           //检查用户名密码是否对应
           if(password==passwordQuery)
           {
               int r=QMessageBox::information(this,tr("Tip"),tr("登录成功！   "),tr(("ok")));
               if(r==tr(("ok")).toInt())
               {
                   this->close();
               }
               menuView.show();
               this->hide();
               emit showmenu();
           }
           else
           {
               QMessageBox::about(this,tr("Tip"),tr("密码错误！请重新输入   "));
               ui->edit_password->setText("");
           }
           break;
       }
   }