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QSqlRelationalTableModel with multiple Joins?

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  • devhobbyD devhobby

    @JonB said in QSqlRelationalTableModel with multiple Joins?:

    @devhobby
    And you are saying that when you double-click...? Nothing at all happens?

    If that is the case, I can only imagine your model is read-only, to do with it being a SELECT and not a table?

    Yes, as stated above I used my custom query to do all the joins.

    By the way, I don't expect to change the database directly.

    I just want to visually edit the cell without applying any changes to the database.

    Once the user changes the text of the cell, the new text is immediately visible and I store it in a QString

    When the user presses the button "Commit changes" I will have a series of changes that the user wants to apply to the database -> I now need to make them real sending a custom query to the database.

    JonBJ Online
    JonBJ Online
    JonB
    wrote on last edited by JonB
    #20

    @devhobby
    I'm a little lost. You wrote:

    Thanks but before doing that, I was wondering if there's a way to change the content of the cell by directly typing into it.

    I thought you were saying when double-click it does not let you edit, nothing happens, or whatever. Now I think you're saying it does let you edit? I don't know if you have a question here?

    devhobbyD 1 Reply Last reply
    0
    • JonBJ JonB

      @devhobby
      I'm a little lost. You wrote:

      Thanks but before doing that, I was wondering if there's a way to change the content of the cell by directly typing into it.

      I thought you were saying when double-click it does not let you edit, nothing happens, or whatever. Now I think you're saying it does let you edit? I don't know if you have a question here?

      devhobbyD Offline
      devhobbyD Offline
      devhobby
      wrote on last edited by devhobby
      #21

      @JonB said in QSqlRelationalTableModel with multiple Joins?:

      @devhobby
      I'm a little lost. You wrote:

      Thanks but before doing that, I was wondering if there's a way to change the content of the cell by directly typing into it.

      I thought you were saying when double-click it does not let you edit, nothing happens, or whatever. Now I think you're saying it does let you edit? I don't know if you have a question here?

      Yes I asked if there's a way to change the content of the cell by directly typing into it

      Because now, when I double click, nothing happens.

      Once the cell is edited, I'd also like to change its background color... but that's another story

      JonBJ 1 Reply Last reply
      0
      • devhobbyD devhobby

        @JonB said in QSqlRelationalTableModel with multiple Joins?:

        @devhobby
        I'm a little lost. You wrote:

        Thanks but before doing that, I was wondering if there's a way to change the content of the cell by directly typing into it.

        I thought you were saying when double-click it does not let you edit, nothing happens, or whatever. Now I think you're saying it does let you edit? I don't know if you have a question here?

        Yes I asked if there's a way to change the content of the cell by directly typing into it

        Because now, when I double click, nothing happens.

        Once the cell is edited, I'd also like to change its background color... but that's another story

        JonBJ Online
        JonBJ Online
        JonB
        wrote on last edited by
        #22

        @devhobby said in QSqlRelationalTableModel with multiple Joins?:

        Once the user changes the text of the cell, the new text is immediately visible and I store it in a QString

        Because now, when I double click, nothing happens.

        Sorry, but if "nothing happens" when you double-click cell to edit, how come you talk about "Once the user changes the text of the cell"? Maybe I'm being dumb, but I just don't get it!

        devhobbyD 1 Reply Last reply
        1
        • JonBJ JonB

          @devhobby said in QSqlRelationalTableModel with multiple Joins?:

          Once the user changes the text of the cell, the new text is immediately visible and I store it in a QString

          Because now, when I double click, nothing happens.

          Sorry, but if "nothing happens" when you double-click cell to edit, how come you talk about "Once the user changes the text of the cell"? Maybe I'm being dumb, but I just don't get it!

          devhobbyD Offline
          devhobbyD Offline
          devhobby
          wrote on last edited by
          #23

          @JonB said in QSqlRelationalTableModel with multiple Joins?:

          @devhobby said in QSqlRelationalTableModel with multiple Joins?:

          Once the user changes the text of the cell, the new text is immediately visible and I store it in a QString

          Because now, when I double click, nothing happens.

          Sorry, but if "nothing happens" when you double-click cell to edit, how come you talk about "Once the user changes the text of the cell"? Maybe I'm being dumb, but I just don't get it!

          Don't worry! I'm sorry, I'm probably using the wrong tenses to express myself.

          "Once the user changes the text of the cell, the new text is immediately visible and I store it in a QString"

          Is the prediction of what I want to happen... and can't manage to make it happen actually

          JonBJ 1 Reply Last reply
          1
          • devhobbyD devhobby

            @JonB said in QSqlRelationalTableModel with multiple Joins?:

            @devhobby said in QSqlRelationalTableModel with multiple Joins?:

            Once the user changes the text of the cell, the new text is immediately visible and I store it in a QString

            Because now, when I double click, nothing happens.

            Sorry, but if "nothing happens" when you double-click cell to edit, how come you talk about "Once the user changes the text of the cell"? Maybe I'm being dumb, but I just don't get it!

            Don't worry! I'm sorry, I'm probably using the wrong tenses to express myself.

            "Once the user changes the text of the cell, the new text is immediately visible and I store it in a QString"

            Is the prediction of what I want to happen... and can't manage to make it happen actually

            JonBJ Online
            JonBJ Online
            JonB
            wrote on last edited by JonB
            #24

            @devhobby

            Is the prediction of what I want to happen... and can't manage to make it happen actually

            Ohhhh...! :)

            OK, I would expect you've done the right stuff. I believe that's what our code does. I can only think of what I suggested: that the SELECT makes the model read-only, and editing is not allowed.

            I shall step aside and you need an expert here to guide you further....

            devhobbyD 1 Reply Last reply
            1
            • JonBJ JonB

              @devhobby

              Is the prediction of what I want to happen... and can't manage to make it happen actually

              Ohhhh...! :)

              OK, I would expect you've done the right stuff. I believe that's what our code does. I can only think of what I suggested: that the SELECT makes the model read-only, and editing is not allowed.

              I shall step aside and you need an expert here to guide you further....

              devhobbyD Offline
              devhobbyD Offline
              devhobby
              wrote on last edited by devhobby
              #25

              @JonB said in QSqlRelationalTableModel with multiple Joins?:

              @devhobby

              Is the prediction of what I want to happen... and can't manage to make it happen actually

              Ohhhh...! :)

              OK, I would expect you've done the right stuff. I believe that's what our code does. I can only think of what I suggested: that the SELECT makes the model read-only, and editing is not allowed.

              I shall step aside and you need an expert here to guide you further....

              Yes, the custom query is most likely keeping my Table View read-only.

              I just want to visually edit the cells...

              This is far more complicated than I thought...

              JonBJ 1 Reply Last reply
              0
              • devhobbyD devhobby

                @JonB said in QSqlRelationalTableModel with multiple Joins?:

                @devhobby

                Is the prediction of what I want to happen... and can't manage to make it happen actually

                Ohhhh...! :)

                OK, I would expect you've done the right stuff. I believe that's what our code does. I can only think of what I suggested: that the SELECT makes the model read-only, and editing is not allowed.

                I shall step aside and you need an expert here to guide you further....

                Yes, the custom query is most likely keeping my Table View read-only.

                I just want to visually edit the cells...

                This is far more complicated than I thought...

                JonBJ Online
                JonBJ Online
                JonB
                wrote on last edited by JonB
                #26

                @devhobby
                http://doc.qt.io/qt-5/qitemdelegate.html#details must be to do with it.

                I could easily be wrong(!), but I thought the idea of the model/view would be that if you edit it would save the value back to the model, not "just give you some string". You can doubtless play with the delegate to do something else...

                P.S.
                Look at http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells:

                Check if the item is actually editable: (MyTable->model()->flags(idx) & Qt::ItemIsEditable). If not, make it so.

                https://stackoverflow.com/questions/28186118/how-to-make-qtableview-to-enter-the-editing-mode-only-on-double-click:

                Setting a Qt.ItemIsEnabled flag makes the QTableView items editable. To enter the item's editing mode the user can simply double-click it.

                EDIT: You have to loop over every item in your table view to make it individually editable....

                devhobbyD 1 Reply Last reply
                2
                • JonBJ JonB

                  @devhobby
                  http://doc.qt.io/qt-5/qitemdelegate.html#details must be to do with it.

                  I could easily be wrong(!), but I thought the idea of the model/view would be that if you edit it would save the value back to the model, not "just give you some string". You can doubtless play with the delegate to do something else...

                  P.S.
                  Look at http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells:

                  Check if the item is actually editable: (MyTable->model()->flags(idx) & Qt::ItemIsEditable). If not, make it so.

                  https://stackoverflow.com/questions/28186118/how-to-make-qtableview-to-enter-the-editing-mode-only-on-double-click:

                  Setting a Qt.ItemIsEnabled flag makes the QTableView items editable. To enter the item's editing mode the user can simply double-click it.

                  EDIT: You have to loop over every item in your table view to make it individually editable....

                  devhobbyD Offline
                  devhobbyD Offline
                  devhobby
                  wrote on last edited by
                  #27

                  @JonB said in QSqlRelationalTableModel with multiple Joins?:

                  @devhobby
                  http://doc.qt.io/qt-5/qitemdelegate.html#details must be to do with it.

                  I could easily be wrong(!), but I thought the idea of the model/view would be that if you edit it would save the value back to the model, not "just give you some string". You can doubtless play with the delegate to do something else...

                  P.S.
                  Look at http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells:

                  Check if the item is actually editable: (MyTable->model()->flags(idx) & Qt::ItemIsEditable). If not, make it so.

                  https://stackoverflow.com/questions/28186118/how-to-make-qtableview-to-enter-the-editing-mode-only-on-double-click:

                  Setting a Qt.ItemIsEnabled flag makes the QTableView items editable. To enter the item's editing mode the user can simply double-click it.

                  I'd like to change Table View's flag to Qt::ItemIsEditable... but can't find a way to do it

                  There's no setFlags() method here...

                  JonBJ 1 Reply Last reply
                  0
                  • devhobbyD devhobby

                    @JonB said in QSqlRelationalTableModel with multiple Joins?:

                    @devhobby
                    http://doc.qt.io/qt-5/qitemdelegate.html#details must be to do with it.

                    I could easily be wrong(!), but I thought the idea of the model/view would be that if you edit it would save the value back to the model, not "just give you some string". You can doubtless play with the delegate to do something else...

                    P.S.
                    Look at http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells:

                    Check if the item is actually editable: (MyTable->model()->flags(idx) & Qt::ItemIsEditable). If not, make it so.

                    https://stackoverflow.com/questions/28186118/how-to-make-qtableview-to-enter-the-editing-mode-only-on-double-click:

                    Setting a Qt.ItemIsEnabled flag makes the QTableView items editable. To enter the item's editing mode the user can simply double-click it.

                    I'd like to change Table View's flag to Qt::ItemIsEditable... but can't find a way to do it

                    There's no setFlags() method here...

                    JonBJ Online
                    JonBJ Online
                    JonB
                    wrote on last edited by JonB
                    #28

                    @devhobby
                    You have to loop over every item in your table view to make it individually editable (if you're not creating the items yourself, or unless someone suggests a way to cause that to happen as it binds to your model, e.g. https://stackoverflow.com/a/28226056/489865)....

                    devhobbyD 1 Reply Last reply
                    1
                    • JonBJ JonB

                      @devhobby
                      You have to loop over every item in your table view to make it individually editable (if you're not creating the items yourself, or unless someone suggests a way to cause that to happen as it binds to your model, e.g. https://stackoverflow.com/a/28226056/489865)....

                      devhobbyD Offline
                      devhobbyD Offline
                      devhobby
                      wrote on last edited by
                      #29

                      @JonB said in QSqlRelationalTableModel with multiple Joins?:

                      @devhobby
                      You have to loop over every item in your table view to make it individually editable (if you're not creating the items yourself, or unless someone suggests a way to cause that to happen as it binds to your model)....

                      Suppose I'm inside a for loop where index is a QModelIndex

                      ui->tableView->model()->data(index). ???
                      

                      There's no setFlags here still

                      JonBJ 1 Reply Last reply
                      0
                      • devhobbyD devhobby

                        @JonB said in QSqlRelationalTableModel with multiple Joins?:

                        @devhobby
                        You have to loop over every item in your table view to make it individually editable (if you're not creating the items yourself, or unless someone suggests a way to cause that to happen as it binds to your model)....

                        Suppose I'm inside a for loop where index is a QModelIndex

                        ui->tableView->model()->data(index). ???
                        

                        There's no setFlags here still

                        JonBJ Online
                        JonBJ Online
                        JonB
                        wrote on last edited by JonB
                        #30

                        @devhobby

                        I think we use QTableWidget, not just QTableView.

                        http://www.qtcentre.org/threads/46245-QTableWidgetItem-setflags-strange-behavior?p=209282#post209282 shows you accessing QTableWidgetItem. http://doc.qt.io/qt-5/qtablewidget.html#item

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

                        The QTableWidget class provides an item-based table view with a default model.
                        Table widgets provide standard table display facilities for applications. The items in a QTableWidget are provided by QTableWidgetItem.
                        If you want a table that uses your own data model you should use QTableView rather than this class.

                        But for QTableView I previously gave you http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells?p=176235#post176235:

                        Qt::ItemFlags MyTableModel::flags (const QModelIndex &index) const
                        {
                           return QAbstractItemModel::flags(index) | Qt::ItemIsEditable;
                        }
                        

                        http://doc.qt.io/qt-5/qabstractitemmodel.html#flags, http://doc.qt.io/qt-5/qabstracttablemodel.html#flags works off the model, so presumably your ui->tableView->model()->flags(index).

                        Ah ha!! Here's what we wanted to know:
                        http://doc.qt.io/qt-5/qsqlquerymodel.html#details

                        The model is read-only by default. To make it read-write, you must subclass it and reimplement setData() and flags(). Another option is to use QSqlTableModel, which provides a read-write model based on a single database table.

                        devhobbyD 1 Reply Last reply
                        1
                        • JonBJ JonB

                          @devhobby

                          I think we use QTableWidget, not just QTableView.

                          http://www.qtcentre.org/threads/46245-QTableWidgetItem-setflags-strange-behavior?p=209282#post209282 shows you accessing QTableWidgetItem. http://doc.qt.io/qt-5/qtablewidget.html#item

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

                          The QTableWidget class provides an item-based table view with a default model.
                          Table widgets provide standard table display facilities for applications. The items in a QTableWidget are provided by QTableWidgetItem.
                          If you want a table that uses your own data model you should use QTableView rather than this class.

                          But for QTableView I previously gave you http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells?p=176235#post176235:

                          Qt::ItemFlags MyTableModel::flags (const QModelIndex &index) const
                          {
                             return QAbstractItemModel::flags(index) | Qt::ItemIsEditable;
                          }
                          

                          http://doc.qt.io/qt-5/qabstractitemmodel.html#flags, http://doc.qt.io/qt-5/qabstracttablemodel.html#flags works off the model, so presumably your ui->tableView->model()->flags(index).

                          Ah ha!! Here's what we wanted to know:
                          http://doc.qt.io/qt-5/qsqlquerymodel.html#details

                          The model is read-only by default. To make it read-write, you must subclass it and reimplement setData() and flags(). Another option is to use QSqlTableModel, which provides a read-write model based on a single database table.

                          devhobbyD Offline
                          devhobbyD Offline
                          devhobby
                          wrote on last edited by devhobby
                          #31

                          @JonB said in QSqlRelationalTableModel with multiple Joins?:

                          @devhobby

                          I think we use QTableWidget, not just QTableView.

                          http://www.qtcentre.org/threads/46245-QTableWidgetItem-setflags-strange-behavior?p=209282#post209282 shows you accessing QTableWidgetItem. http://doc.qt.io/qt-5/qtablewidget.html#item

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

                          The QTableWidget class provides an item-based table view with a default model.
                          Table widgets provide standard table display facilities for applications. The items in a QTableWidget are provided by QTableWidgetItem.
                          If you want a table that uses your own data model you should use QTableView rather than this class.

                          But for QTableView I previously gave you http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells?p=176235#post176235:

                          Qt::ItemFlags MyTableModel::flags (const QModelIndex &index) const
                          {
                             return QAbstractItemModel::flags(index) | Qt::ItemIsEditable;
                          }
                          

                          At this point I don't even know which of the 2 (table view/table widget) is the most appropriate for my situation.

                          The last post you linked says to reimplement the method flags() but I don't understand: after inheriting from AbstractItemModel (and reimplementing the method), what am I supposed to do?

                          JonBJ 2 Replies Last reply
                          0
                          • devhobbyD devhobby

                            @JonB said in QSqlRelationalTableModel with multiple Joins?:

                            @devhobby

                            I think we use QTableWidget, not just QTableView.

                            http://www.qtcentre.org/threads/46245-QTableWidgetItem-setflags-strange-behavior?p=209282#post209282 shows you accessing QTableWidgetItem. http://doc.qt.io/qt-5/qtablewidget.html#item

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

                            The QTableWidget class provides an item-based table view with a default model.
                            Table widgets provide standard table display facilities for applications. The items in a QTableWidget are provided by QTableWidgetItem.
                            If you want a table that uses your own data model you should use QTableView rather than this class.

                            But for QTableView I previously gave you http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells?p=176235#post176235:

                            Qt::ItemFlags MyTableModel::flags (const QModelIndex &index) const
                            {
                               return QAbstractItemModel::flags(index) | Qt::ItemIsEditable;
                            }
                            

                            At this point I don't even know which of the 2 (table view/table widget) is the most appropriate for my situation.

                            The last post you linked says to reimplement the method flags() but I don't understand: after inheriting from AbstractItemModel (and reimplementing the method), what am I supposed to do?

                            JonBJ Online
                            JonBJ Online
                            JonB
                            wrote on last edited by JonB
                            #32

                            @devhobby
                            Look at the last bit I just added to my post above.

                            To make it [QSqlQueryModel] read-write, you must subclass it and reimplement setData() and flags().

                            (And BTW when you've done that there won't be any "iterating over items and setting the editable flag", your items will be editable through your reimplementation of QSqlQueryModel::flags().)

                            You understand how to "subclass", and how to "reimplement [override] virtual methods", don't you?

                            devhobbyD 1 Reply Last reply
                            1
                            • devhobbyD devhobby

                              @JonB said in QSqlRelationalTableModel with multiple Joins?:

                              @devhobby

                              I think we use QTableWidget, not just QTableView.

                              http://www.qtcentre.org/threads/46245-QTableWidgetItem-setflags-strange-behavior?p=209282#post209282 shows you accessing QTableWidgetItem. http://doc.qt.io/qt-5/qtablewidget.html#item

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

                              The QTableWidget class provides an item-based table view with a default model.
                              Table widgets provide standard table display facilities for applications. The items in a QTableWidget are provided by QTableWidgetItem.
                              If you want a table that uses your own data model you should use QTableView rather than this class.

                              But for QTableView I previously gave you http://www.qtcentre.org/threads/38338-Can-t-edit-my-QTableView-cells?p=176235#post176235:

                              Qt::ItemFlags MyTableModel::flags (const QModelIndex &index) const
                              {
                                 return QAbstractItemModel::flags(index) | Qt::ItemIsEditable;
                              }
                              

                              At this point I don't even know which of the 2 (table view/table widget) is the most appropriate for my situation.

                              The last post you linked says to reimplement the method flags() but I don't understand: after inheriting from AbstractItemModel (and reimplementing the method), what am I supposed to do?

                              JonBJ Online
                              JonBJ Online
                              JonB
                              wrote on last edited by JonB
                              #33

                              @devhobby
                              I'm going back to your very original post and thinking about what you're actually trying to achieve anyway. The code we're talking about is all well & good, if you want to proceed, but I'm wondering about your expectations of the interface.

                              In your pic of Employee table only, you have 1 row per employee. When you say:

                              I want to join the Employee table with EmployeePosition and EmployeeResource so that I can also see, for each employee, their positions and resources (if they have any!)

                              what are you expecting the table interface to be for the multiple positions & resources you say employees have?

                              It's all very well to say:

                              What I need, hence, is a full outer join
                              The query above gives me everything I want to know and see on the Table View

                              [I'm trusting that your code implements FULL OUTER JOIN] but left to its own devices this will mean you have many rows per employee, for each position/resource variant. Is that what you intend??

                              One thing to understand: when you're using QSqlRelationalTableModel so that you can "look up" position/resource names, the combobox you'll get will only ever allow single selection, if you're imagining that it might provide multiple selection it won't.

                              1 Reply Last reply
                              1
                              • JonBJ JonB

                                @devhobby
                                Look at the last bit I just added to my post above.

                                To make it [QSqlQueryModel] read-write, you must subclass it and reimplement setData() and flags().

                                (And BTW when you've done that there won't be any "iterating over items and setting the editable flag", your items will be editable through your reimplementation of QSqlQueryModel::flags().)

                                You understand how to "subclass", and how to "reimplement [override] virtual methods", don't you?

                                devhobbyD Offline
                                devhobbyD Offline
                                devhobby
                                wrote on last edited by devhobby
                                #34

                                @JonB said in QSqlRelationalTableModel with multiple Joins?:

                                @devhobby
                                Look at the last bit I just added to my post above.

                                To make it [QSqlQueryModel] read-write, you must subclass it and reimplement setData() and flags().

                                (And BTW when you've done that there won't be any "iterating over items and setting the editable flag", your items will be editable through your reimplementation of QSqlQueryModel::flags().)

                                You understand how to "subclass", and how to "reimplement [override] virtual methods", don't you?

                                I have my CustomModel class now deriving from QSqlQueryModel

                                #ifndef CUSTOMMODEL_H
                                #define CUSTOMMODEL_H
                                #include <QSqlQueryModel>
                                
                                class CustomModel : public QSqlQueryModel
                                {
                                    Q_OBJECT
                                    
                                public:
                                    bool setData(const QModelIndex &index, const QVariant &value, int role) override;
                                    Qt::ItemFlags flags(const QModelIndex &index) const override;
                                };
                                
                                #endif
                                

                                The problem is...

                                0_1518117868934_4f8b1d3f-c5cf-43c9-b900-be0b15d1ac81-image.png

                                The linker somehow can't match the signatures... weird.

                                I checked this link for example [ https://code.woboq.org/qt5/qtbase/src/corelib/itemmodels/qabstractitemmodel.h.html ]

                                and both setData() and flags() are the same way I overloaded them...

                                JonBJ 1 Reply Last reply
                                0
                                • devhobbyD devhobby

                                  @JonB said in QSqlRelationalTableModel with multiple Joins?:

                                  @devhobby
                                  Look at the last bit I just added to my post above.

                                  To make it [QSqlQueryModel] read-write, you must subclass it and reimplement setData() and flags().

                                  (And BTW when you've done that there won't be any "iterating over items and setting the editable flag", your items will be editable through your reimplementation of QSqlQueryModel::flags().)

                                  You understand how to "subclass", and how to "reimplement [override] virtual methods", don't you?

                                  I have my CustomModel class now deriving from QSqlQueryModel

                                  #ifndef CUSTOMMODEL_H
                                  #define CUSTOMMODEL_H
                                  #include <QSqlQueryModel>
                                  
                                  class CustomModel : public QSqlQueryModel
                                  {
                                      Q_OBJECT
                                      
                                  public:
                                      bool setData(const QModelIndex &index, const QVariant &value, int role) override;
                                      Qt::ItemFlags flags(const QModelIndex &index) const override;
                                  };
                                  
                                  #endif
                                  

                                  The problem is...

                                  0_1518117868934_4f8b1d3f-c5cf-43c9-b900-be0b15d1ac81-image.png

                                  The linker somehow can't match the signatures... weird.

                                  I checked this link for example [ https://code.woboq.org/qt5/qtbase/src/corelib/itemmodels/qabstractitemmodel.h.html ]

                                  and both setData() and flags() are the same way I overloaded them...

                                  JonBJ Online
                                  JonBJ Online
                                  JonB
                                  wrote on last edited by JonB
                                  #35

                                  @devhobby
                                  Now you're talking C++ esotericism, and I'm a Python Qt guy anyway. This one is your problem! :) Sometimes signatures don't match if you don't get your consts just right? What about the Q_INVOKABLE?

                                  https://stackoverflow.com/questions/33781346/how-to-write-setdata-in-qsqlquerymodelqabstractitemmodel is an example of what claims to work? (Oohh, it uses Q_DECL_OVERRIDE for your override?)

                                  devhobbyD 1 Reply Last reply
                                  1
                                  • JonBJ JonB

                                    @devhobby
                                    Now you're talking C++ esotericism, and I'm a Python Qt guy anyway. This one is your problem! :) Sometimes signatures don't match if you don't get your consts just right? What about the Q_INVOKABLE?

                                    https://stackoverflow.com/questions/33781346/how-to-write-setdata-in-qsqlquerymodelqabstractitemmodel is an example of what claims to work? (Oohh, it uses Q_DECL_OVERRIDE for your override?)

                                    devhobbyD Offline
                                    devhobbyD Offline
                                    devhobby
                                    wrote on last edited by devhobby
                                    #36

                                    @JonB said in QSqlRelationalTableModel with multiple Joins?:

                                    @devhobby
                                    Oohh, it uses Q_DECL_OVERRIDE for your override?

                                    Yes, it is ALSO that.

                                    Something strange is going on here...

                                    I'll try tagging someone @SGaist @VRonin

                                    --- HEADER FILE ---

                                    #ifndef MYMODEL_H
                                    #define MYMODEL_H
                                    
                                    #include <QObject>
                                    #include <QSqlQueryModel>
                                    
                                    class MyModel : public QSqlQueryModel
                                    {
                                        Q_OBJECT
                                    
                                    public:
                                        MyModel(QObject *parent = 0);
                                    
                                        Qt::ItemFlags flags(const QModelIndex &index) const override;
                                        bool setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole) override;
                                    };
                                    
                                    #endif // MYMODEL_H
                                    

                                    --- CPP FILE ---

                                    #include "mymodel.h"
                                    
                                    MyModel::MyModel(QObject *parent) : QSqlQueryModel(parent)
                                    {
                                    }
                                    
                                    Qt::ItemFlags MyModel::flags(const QModelIndex &index) const
                                    {
                                    
                                    }
                                    
                                    bool MyModel::setData(const QModelIndex &index, const QVariant &value, int role)
                                    {
                                    
                                    }
                                    

                                    0_1518119620573_1720abc4-b3c2-4451-9dda-e5b727282cf3-image.png

                                    1 Reply Last reply
                                    0
                                    • SGaistS Offline
                                      SGaistS Offline
                                      SGaist
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #37

                                      Your CPP file contains an error, the default value should be in the declaration of the function.

                                      If you are using Qt >= 5.7, you can simply use the override keyword as C++11 support is mandatory since that version. Q_DECL_OVERRIDE was used to allow compatibly with non-C++11 enabled compilers.

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

                                      JonBJ devhobbyD 2 Replies Last reply
                                      2
                                      • SGaistS SGaist

                                        Your CPP file contains an error, the default value should be in the declaration of the function.

                                        If you are using Qt >= 5.7, you can simply use the override keyword as C++11 support is mandatory since that version. Q_DECL_OVERRIDE was used to allow compatibly with non-C++11 enabled compilers.

                                        JonBJ Online
                                        JonBJ Online
                                        JonB
                                        wrote on last edited by
                                        #38

                                        @SGaist You're a hero ;-) It takes you like 1 minute to spot it & reply!

                                        1 Reply Last reply
                                        1
                                        • SGaistS SGaist

                                          Your CPP file contains an error, the default value should be in the declaration of the function.

                                          If you are using Qt >= 5.7, you can simply use the override keyword as C++11 support is mandatory since that version. Q_DECL_OVERRIDE was used to allow compatibly with non-C++11 enabled compilers.

                                          devhobbyD Offline
                                          devhobbyD Offline
                                          devhobby
                                          wrote on last edited by devhobby
                                          #39

                                          @SGaist said in QSqlRelationalTableModel with multiple Joins?:

                                          Your CPP file contains an error, the default value should be in the declaration of the function.

                                          If you are using Qt >= 5.7, you can simply use the override keyword as C++11 support is mandatory since that version. Q_DECL_OVERRIDE was used to allow compatibly with non-C++11 enabled compilers.

                                          I hoped it was just that...

                                          0_1518120023429_f174cbae-ee6a-42fa-b713-287d8d891eff-image.png

                                          I moved the default value in the header file, same issue

                                          [ I will update the code posted above so that I don't repost it everytime ]

                                          1 Reply Last reply
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