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. QTableview data disappear..
Forum Updated to NodeBB v4.3 + New Features

QTableview data disappear..

Scheduled Pinned Locked Moved Solved General and Desktop
19 Posts 4 Posters 2.4k Views 1 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 Christian Ehrlicher

    It works as long as the model does not need to refetch data from the database (e.g. due to scrolling or other circumstances).

    TheCipo76T Offline
    TheCipo76T Offline
    TheCipo76
    wrote on last edited by TheCipo76
    #9

    @Christian-Ehrlicher No, i'have tried to scroll and works fine.

    This is only view of DB data.. no need to modify nothing in this dialog
    and no need to reload data

    1 Reply Last reply
    0
    • Christian EhrlicherC Offline
      Christian EhrlicherC Offline
      Christian Ehrlicher
      Lifetime Qt Champion
      wrote on last edited by
      #10

      I'm giving up... would you please at least try to not to close the database and see if your problem goes away?

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

      TheCipo76T 1 Reply Last reply
      0
      • Christian EhrlicherC Christian Ehrlicher

        I'm giving up... would you please at least try to not to close the database and see if your problem goes away?

        TheCipo76T Offline
        TheCipo76T Offline
        TheCipo76
        wrote on last edited by TheCipo76
        #11

        @Christian-Ehrlicher Yes, i have putted "//" before close database instruction

        //mDatabase.close();
        

        but warning still remain..

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

          Are you calling QSqlDatabase::addDatabase("QMYSQL"); in several places in your application ?

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

          TheCipo76T 1 Reply Last reply
          1
          • SGaistS SGaist

            Are you calling QSqlDatabase::addDatabase("QMYSQL"); in several places in your application ?

            TheCipo76T Offline
            TheCipo76T Offline
            TheCipo76
            wrote on last edited by TheCipo76
            #13

            @SGaist Yes, in every dialog who need to connect to database..

            but in every dialog call

            ordforauto::~ordforauto()
            {
                if (aDatabase.open()) {
                    aDatabase.close();
                }
            QSqlDatabase::removeDatabase("QMYSQL");
                delete ui;
            }
            

            in the code or at least in the unload istructions as you see

            1 Reply Last reply
            0
            • Christian EhrlicherC Offline
              Christian EhrlicherC Offline
              Christian Ehrlicher
              Lifetime Qt Champion
              wrote on last edited by
              #14

              http://doc.qt.io/qt-5/qsqlquery.html#details

              Warning: You must load the SQL driver and open the connection before a QSqlQuery is created. Also, the connection must remain open while the query exists; otherwise, the behavior of QSqlQuery is undefined.

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

              TheCipo76T 1 Reply Last reply
              1
              • SGaistS Offline
                SGaistS Offline
                SGaist
                Lifetime Qt Champion
                wrote on last edited by
                #15

                Why are you doing it like that ? There's no need to nuke and recreate the connection each time.

                If you really want to do it like that, then you should create a connection with a different name in each of your dialog.

                Because currently, you are manipulating the default connection from several places in a wrong manner.

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

                TheCipo76T 1 Reply Last reply
                2
                • SGaistS SGaist

                  Why are you doing it like that ? There's no need to nuke and recreate the connection each time.

                  If you really want to do it like that, then you should create a connection with a different name in each of your dialog.

                  Because currently, you are manipulating the default connection from several places in a wrong manner.

                  TheCipo76T Offline
                  TheCipo76T Offline
                  TheCipo76
                  wrote on last edited by
                  #16

                  @SGaist ok, i create the connection in the main window
                  and then only open/close database tables in every dialog?

                  is it right?

                  1 Reply Last reply
                  0
                  • Christian EhrlicherC Christian Ehrlicher

                    http://doc.qt.io/qt-5/qsqlquery.html#details

                    Warning: You must load the SQL driver and open the connection before a QSqlQuery is created. Also, the connection must remain open while the query exists; otherwise, the behavior of QSqlQuery is undefined.

                    TheCipo76T Offline
                    TheCipo76T Offline
                    TheCipo76
                    wrote on last edited by TheCipo76
                    #17

                    @Christian-Ehrlicher i will check all dialogs.. but i think that is what i've done..

                    jsulmJ 1 Reply Last reply
                    0
                    • TheCipo76T TheCipo76

                      @Christian-Ehrlicher i will check all dialogs.. but i think that is what i've done..

                      jsulmJ Online
                      jsulmJ Online
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #18

                      @TheCipo76 As shown here: http://doc.qt.io/qt-5/qsqldatabase.html
                      Create and open db connection:

                      QSqlDatabase db = QSqlDatabase::addDatabase("QPSQL");
                      db.setHostName("acidalia");
                      db.setDatabaseName("customdb");
                      db.setUserName("mojito");
                      db.setPassword("J0a1m8");
                      bool ok = db.open();
                      

                      When you need the connection just get it:

                      QSqlDatabase db = QSqlDatabase::database();
                      

                      No need to open and close it all the time.

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      TheCipo76T 1 Reply Last reply
                      4
                      • jsulmJ jsulm

                        @TheCipo76 As shown here: http://doc.qt.io/qt-5/qsqldatabase.html
                        Create and open db connection:

                        QSqlDatabase db = QSqlDatabase::addDatabase("QPSQL");
                        db.setHostName("acidalia");
                        db.setDatabaseName("customdb");
                        db.setUserName("mojito");
                        db.setPassword("J0a1m8");
                        bool ok = db.open();
                        

                        When you need the connection just get it:

                        QSqlDatabase db = QSqlDatabase::database();
                        

                        No need to open and close it all the time.

                        TheCipo76T Offline
                        TheCipo76T Offline
                        TheCipo76
                        wrote on last edited by
                        #19

                        @jsulm Ok, i've modify all my project and all works ok!

                        Thanks to all for help!

                        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