Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. Wont show another window
Qt 6.11 is out! See what's new in the release blog

Wont show another window

Scheduled Pinned Locked Moved Solved General and Desktop
16 Posts 5 Posters 4.2k Views 4 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • Christian EhrlicherC Offline
    Christian EhrlicherC Offline
    Christian Ehrlicher
    Lifetime Qt Champion
    wrote on last edited by
    #2

    So what do you get exactly? QSqlQuery::prepare() and bindValue() have a return value which should be checked. Also QSqlQuery:lastError() should be used.

    Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
    Visit the Qt Academy at https://academy.qt.io/catalog

    1 Reply Last reply
    1
    • E Eternus
         if(db.open()) {
              QMessageBox::information(this,"QMYSQL", "Sucesfull");
              QString username = ui->lineEdit_username->text();
              QString password = ui->lineEdit_password->text();
      
      
      
              QSqlQuery query(QSqlDatabase::database("QTUSERS"));
              query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password"));
      
      
              query.bindValue(":username", username);
              query.bindValue(":username", password);
      
              if(!query.exec()){
                  QMessageBox::information(this, "Failed", "Nepodarilo sa pripojit na query");
              } else {
                  while(query.next()){
                      QString usernameFromDB = query.value(1).toString();
                      QString passwordFromDB = query.value(2).toString();
      
                      qDebug()<<(usernameFromDB == username)<<(passwordFromDB == password);
      
                      if (usernameFromDB == username && passwordFromDB == password)  {
                          QMessageBox::information(this, "Uspesne", "Pripojil si query");
                          qDebug()<<"ops!";
      
      
      
                          Dialog logiin;
                          logiin.setModal(true);
                          logiin.show();
                          logiin.exec();
      
      
                      } else {
                          QMessageBox::information (this, "Failed", "Nepodarilo sa pripojit!");
                      }
      
                      }
                  }
              }   else {
              QMessageBox::information(this,"QMYSQL", "Database not found");
          }
      
      
      
          }
      

      if login my app nothing happend only "Succesfull" succes is connect db correct but i cant connect to username and password i think i mean this :

                 while(query.next()){
                      QString usernameFromDB = query.value(1).toString();
                      QString passwordFromDB = query.value(2).toString();
      
                      qDebug()<<(usernameFromDB == username)<<(passwordFromDB == password);
      
                      if (usernameFromDB == username && passwordFromDB == password)  {
                          QMessageBox::information(this, "Uspesne", "Pripojil si query");
                          qDebug()<<"ops!";
      

      this is my database :

      Screenshot 2020-09-20 at 21.52.53.png

      JonBJ Online
      JonBJ Online
      JonB
      wrote on last edited by JonB
      #3

      @Eternus said in Wont show another window:

      query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password"));

      Bad query. To the best of my knowledge, unless MySQL is strangely C-/Python-like.

      1 Reply Last reply
      0
      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #4

        Hi,

        You are missing a : before password and you are binding twice to username.

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

        JonBJ 1 Reply Last reply
        1
        • SGaistS SGaist

          Hi,

          You are missing a : before password and you are binding twice to username.

          JonBJ Online
          JonBJ Online
          JonB
          wrote on last edited by JonB
          #5

          @SGaist said in Wont show another window:

          You are missing a : before password

          It is missing the whole = :password after password, I assume.

          E 1 Reply Last reply
          0
          • JonBJ JonB

            @SGaist said in Wont show another window:

            You are missing a : before password

            It is missing the whole = :password after password, I assume.

            E Offline
            E Offline
            Eternus
            wrote on last edited by Eternus
            #6

            @JonB @SGaist
            if i put this :

                    query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password :password"));
            
            

            its says me this : if(!query.exec()){
            QMessageBox::information(this, "Failed", "Nepodarilo sa pripojit na query");

            but i dont know why mysql server running...

            JonBJ 1 Reply Last reply
            0
            • E Eternus

              @JonB @SGaist
              if i put this :

                      query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password :password"));
              
              

              its says me this : if(!query.exec()){
              QMessageBox::information(this, "Failed", "Nepodarilo sa pripojit na query");

              but i dont know why mysql server running...

              JonBJ Online
              JonBJ Online
              JonB
              wrote on last edited by
              #7

              @Eternus said in Wont show another window:

              AND password :password

              Your query is still wrong. If you do not know what to put here you are going to struggle with MySQL.

              E 1 Reply Last reply
              0
              • JonBJ JonB

                @Eternus said in Wont show another window:

                AND password :password

                Your query is still wrong. If you do not know what to put here you are going to struggle with MySQL.

                E Offline
                E Offline
                Eternus
                wrote on last edited by Eternus
                #8

                @JonB query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password = :password"));

                if i put this its like before nothing show me ... not even that : QMessageBox::information(this, "Failed", "Nepodarilo sa pripojit na query");

                JonBJ 1 Reply Last reply
                0
                • E Eternus

                  @JonB query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password = :password"));

                  if i put this its like before nothing show me ... not even that : QMessageBox::information(this, "Failed", "Nepodarilo sa pripojit na query");

                  JonBJ Online
                  JonBJ Online
                  JonB
                  wrote on last edited by
                  #9

                  @Eternus said in Wont show another window:

                  not even that : QMessageBox::information(this, "Failed", "Nepodarilo sa pripojit na query");

                  That's because for the first time you actually have a legitimate query.

                  E 1 Reply Last reply
                  0
                  • JonBJ JonB

                    @Eternus said in Wont show another window:

                    not even that : QMessageBox::information(this, "Failed", "Nepodarilo sa pripojit na query");

                    That's because for the first time you actually have a legitimate query.

                    E Offline
                    E Offline
                    Eternus
                    wrote on last edited by
                    #10

                    @JonB what you mean ?
                    i just following the tutorial.. and in turorial its works...

                    JonBJ 2 Replies Last reply
                    0
                    • E Eternus

                      @JonB what you mean ?
                      i just following the tutorial.. and in turorial its works...

                      JonBJ Online
                      JonBJ Online
                      JonB
                      wrote on last edited by JonB
                      #11

                      @Eternus
                      You couldn't have followed whatever tutorial, because first you wrote

                      AND password
                      

                      then you wrote

                      AND password :password
                      

                      and now you write

                      AND password = :password
                      

                      So how could the tutorial you are following have all 3 of these, when only the last one is a correct query? And you had at least your query.bindValue()s wrong, I don't know what else. Maybe you have not been correctly copying from the tutorial?

                      1 Reply Last reply
                      0
                      • SGaistS Offline
                        SGaistS Offline
                        SGaist
                        Lifetime Qt Champion
                        wrote on last edited by
                        #12

                        Beside the good points of @JonB, does your database actually contain data ?

                        Interested in AI ? www.idiap.ch
                        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                        1 Reply Last reply
                        0
                        • E Eternus

                          @JonB what you mean ?
                          i just following the tutorial.. and in turorial its works...

                          JonBJ Online
                          JonBJ Online
                          JonB
                          wrote on last edited by JonB
                          #13

                          @Eternus
                          Your code now does not error because it is syntactically correct. If it does not enter your output loop it is because there are simply no matching records for your SELECT statement. Either no rows have the username/password you are supplying, or as @SGaist says you simply have not put any rows into the table.

                          E 1 Reply Last reply
                          1
                          • JonBJ JonB

                            @Eternus
                            Your code now does not error because it is syntactically correct. If it does not enter your output loop it is because there are simply no matching records for your SELECT statement. Either no rows have the username/password you are supplying, or as @SGaist says you simply have not put any rows into the table.

                            E Offline
                            E Offline
                            Eternus
                            wrote on last edited by
                            #14

                            @JonB Solved thanks guyz

                            Pablo J. RoginaP 1 Reply Last reply
                            0
                            • E Eternus

                              @JonB Solved thanks guyz

                              Pablo J. RoginaP Offline
                              Pablo J. RoginaP Offline
                              Pablo J. Rogina
                              wrote on last edited by
                              #15

                              @Eternus said in Wont show another window:

                              Solved thanks guyz

                              Would you mind sharing what the solution was? For the benefit of other users of the forum...

                              Upvote the answer(s) that helped you solve the issue
                              Use "Topic Tools" button to mark your post as Solved
                              Add screenshots via postimage.org
                              Don't ask support requests via chat/PM. Please use the forum so others can benefit from the solution in the future

                              E 1 Reply Last reply
                              0
                              • Pablo J. RoginaP Pablo J. Rogina

                                @Eternus said in Wont show another window:

                                Solved thanks guyz

                                Would you mind sharing what the solution was? For the benefit of other users of the forum...

                                E Offline
                                E Offline
                                Eternus
                                wrote on last edited by Eternus
                                #16

                                @Pablo-J-Rogina
                                ```
                                QSqlQuery query(QSqlDatabase::database("QTUSERS"));

                                
                                to 
                                

                                QSqlQuery query(QSqlDatabase::database("MyConnect"));

                                and 
                                        ```
                                query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password"));
                                

                                to
                                ```
                                query.prepare(QString("SELECT * FROM Users_QT WHERE username = :username AND password = : password"));

                                1 Reply Last reply
                                0

                                • Login

                                • Login or register to search.
                                • First post
                                  Last post
                                0
                                • Categories
                                • Recent
                                • Tags
                                • Popular
                                • Users
                                • Groups
                                • Search
                                • Get Qt Extensions
                                • Unsolved