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QAbstractListModel - dataChanged

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  • E Offline
    E Offline
    Eeli K
    wrote on last edited by
    #10

    You haven't shown your qml code, the problem might be there, in the view or delegate.

    1 Reply Last reply
    2
    • Julien BJ Julien B

      @goxx00

      Try replacing if(role==Qt::EditRole) by if(role==ValueRole) in your setData method.

      Are you sure your data is properly writed in labels_p in your code (checked with the debugger or a simple qDebug)?

      How do you write your value data in your qml?

      G Offline
      G Offline
      goxx00
      wrote on last edited by
      #11

      @Julien-B said in QAbstractListModel - dataChanged:

      Try replacing if(role==Qt::EditRole) by if(role==ValueRole) in your setData method.
      Are you sure your data is properly writed in labels_p in your code (checked with the debugger or a simple qDebug)?

      Now the values get updated in the labels_p. You were right. Before I corrected the typing error it worked too :D

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      0
      • G Offline
        G Offline
        goxx00
        wrote on last edited by goxx00
        #12
         GridView {
                            id:contentView
                            anchors.fill: parent
                            cellWidth: 200
                            cellHeight: 105
                            flow: GridView.FlowLeftToRight
                            layoutDirection: Qt.LeftToRight
                            verticalLayoutDirection: GridView.TopToBottom
                            model: dataModel
        
        
                            delegate: gridViewtemplate
                        }
        

        ...

        Component {
                id: gridViewtemplate
        
        
                        Rectangle {
                        width: 190
                        height: 85
                        color: "#4c4c4c"
                             Label {
                                 id:lname
                                  anchors.horizontalCenter: parent.horizontalCenter
                                  color: "#cccccc"
                                  anchors.margins: 5
                                  anchors.top: parent.top
                                  text: labelname
                                  font.pixelSize: 20
                             }
                             Label {
                                 anchors.left: parent.left
                                 color: "#cccccc"
                                 anchors.bottom: parent.bottom
                                 anchors.margins: 5
                                 text: value
                                 font.pixelSize: 25
        
                                Label {
                                    anchors.left: parent.right
                                    color: "#cccccc"
                                    anchors.verticalCenter: parent.verticalCenter
                                    anchors.margins: 5
                                    text: unit
                                    font.pixelSize: 10
                                }
                             }
                      }
        
              }
        

        In my main.cpp I set the context property datamodel to an object of my Page class.

        engine.rootContext()->setContextProperty("dataModel",connector.data2);
        

        connector is the class where i implemented my sockets and where I have the data2-object, which is a Page object. I am aiming for displaying the data2 object in the gridview.
        The connector runs in a second thread.

        G E 2 Replies Last reply
        0
        • G goxx00
           GridView {
                              id:contentView
                              anchors.fill: parent
                              cellWidth: 200
                              cellHeight: 105
                              flow: GridView.FlowLeftToRight
                              layoutDirection: Qt.LeftToRight
                              verticalLayoutDirection: GridView.TopToBottom
                              model: dataModel
          
          
                              delegate: gridViewtemplate
                          }
          

          ...

          Component {
                  id: gridViewtemplate
          
          
                          Rectangle {
                          width: 190
                          height: 85
                          color: "#4c4c4c"
                               Label {
                                   id:lname
                                    anchors.horizontalCenter: parent.horizontalCenter
                                    color: "#cccccc"
                                    anchors.margins: 5
                                    anchors.top: parent.top
                                    text: labelname
                                    font.pixelSize: 20
                               }
                               Label {
                                   anchors.left: parent.left
                                   color: "#cccccc"
                                   anchors.bottom: parent.bottom
                                   anchors.margins: 5
                                   text: value
                                   font.pixelSize: 25
          
                                  Label {
                                      anchors.left: parent.right
                                      color: "#cccccc"
                                      anchors.verticalCenter: parent.verticalCenter
                                      anchors.margins: 5
                                      text: unit
                                      font.pixelSize: 10
                                  }
                               }
                        }
          
                }
          

          In my main.cpp I set the context property datamodel to an object of my Page class.

          engine.rootContext()->setContextProperty("dataModel",connector.data2);
          

          connector is the class where i implemented my sockets and where I have the data2-object, which is a Page object. I am aiming for displaying the data2 object in the gridview.
          The connector runs in a second thread.

          G Offline
          G Offline
          goxx00
          wrote on last edited by
          #13
          This post is deleted!
          1 Reply Last reply
          0
          • G goxx00
             GridView {
                                id:contentView
                                anchors.fill: parent
                                cellWidth: 200
                                cellHeight: 105
                                flow: GridView.FlowLeftToRight
                                layoutDirection: Qt.LeftToRight
                                verticalLayoutDirection: GridView.TopToBottom
                                model: dataModel
            
            
                                delegate: gridViewtemplate
                            }
            

            ...

            Component {
                    id: gridViewtemplate
            
            
                            Rectangle {
                            width: 190
                            height: 85
                            color: "#4c4c4c"
                                 Label {
                                     id:lname
                                      anchors.horizontalCenter: parent.horizontalCenter
                                      color: "#cccccc"
                                      anchors.margins: 5
                                      anchors.top: parent.top
                                      text: labelname
                                      font.pixelSize: 20
                                 }
                                 Label {
                                     anchors.left: parent.left
                                     color: "#cccccc"
                                     anchors.bottom: parent.bottom
                                     anchors.margins: 5
                                     text: value
                                     font.pixelSize: 25
            
                                    Label {
                                        anchors.left: parent.right
                                        color: "#cccccc"
                                        anchors.verticalCenter: parent.verticalCenter
                                        anchors.margins: 5
                                        text: unit
                                        font.pixelSize: 10
                                    }
                                 }
                          }
            
                  }
            

            In my main.cpp I set the context property datamodel to an object of my Page class.

            engine.rootContext()->setContextProperty("dataModel",connector.data2);
            

            connector is the class where i implemented my sockets and where I have the data2-object, which is a Page object. I am aiming for displaying the data2 object in the gridview.
            The connector runs in a second thread.

            E Offline
            E Offline
            Eeli K
            wrote on last edited by
            #14

            @goxx00 Does the grid show the values when it is shown the first time? Does Application Output in Qt Creator give any qml errors?

            1 Reply Last reply
            1
            • G Offline
              G Offline
              goxx00
              wrote on last edited by
              #15

              It shows nothing and in the application output occur no errors.
              When I refresh the context property everytime I change something, then the model gets displayed.

              1 Reply Last reply
              0
              • G Offline
                G Offline
                goxx00
                wrote on last edited by
                #16

                When I update the context property after adding the labels it works. But this shows me that my addLabel function has a mistake or do i have to emit a signal when i add an item to my QList ?
                I thought the insertRows function do that.

                Thanks a lot for your help :)

                E 1 Reply Last reply
                0
                • G goxx00

                  When I update the context property after adding the labels it works. But this shows me that my addLabel function has a mistake or do i have to emit a signal when i add an item to my QList ?
                  I thought the insertRows function do that.

                  Thanks a lot for your help :)

                  E Offline
                  E Offline
                  Eeli K
                  wrote on last edited by
                  #17

                  @goxx00 Basically the data() method should work because data is shown once. Unless you want to edit the values through the GUI (make them user editable) you don't need the setData function. You can just read or receive the values from the socket, store them in some form and then decide in your reading/receiving code what kind of signal should be emitted to notify the view about the changes. If the amount of rows stays the same, emit dataChanged with the indexes of the first and the last changed row. If rows are added, call begin/endInsertRows(). If much of the data is changed and the amount of rows changes, it's easiest to call begin/endResetModel().

                  When the view receives a signal it automatically decides how to fetch and update the visible data. In any case it calls your model's data() function.

                  I assume you have read the Subclassing section of the documentation and implemented rowCount and roleNames functions (probably it wouldn't work the first time unless you haven't).

                  1 Reply Last reply
                  2
                  • G Offline
                    G Offline
                    goxx00
                    wrote on last edited by
                    #18

                    Thank you very much. For sure, I have read the section and implemented the rowCount(), the flags() and the roleNames() functions. I hope I will get it it now.

                    THANK YOU VERY MUCH!!!

                    1 Reply Last reply
                    0
                    • G Offline
                      G Offline
                      goxx00
                      wrote on last edited by
                      #19

                      Ok I am not ready yet :D I have the next problem maybe you can help me with it.
                      When I add an Item to the QList, with the addLabel function I get an error:

                      QObject::connect:: Cannot queue arguments of type 'QQmlChangeSet'
                      (Make sure 'QQmlChangeSet' is registered using qRegisterMetaType().)
                      

                      I searched for a solution but I didnt found sth. that worked.
                      I thin k it has to do with the fact that the object is in another Thread than the GUI.

                      1 Reply Last reply
                      0

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