Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. QML and Qt Quick
  4. [SOLVED] receiving list from c++ to qml listview
Forum Updated to NodeBB v4.3 + New Features

[SOLVED] receiving list from c++ to qml listview

Scheduled Pinned Locked Moved QML and Qt Quick
22 Posts 5 Posters 25.8k 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.
  • K Offline
    K Offline
    kkrzewniak
    wrote on last edited by
    #2

    Please add some new lines to your code.

    Expose a QAbstractListModel subclass as a context property or by using a Q_INVOAKABLE method.
    Other options are using a QStringList or a QList<QObject> as the model.

    Remember to register your QAbstractListModel subclass if you'll not be exposing it via context property.
    qmlRegisterUncreatableType/qmlRegisterType

    Me, Grimlock, not "nice dino". ME BASH BRAINS!

    1 Reply Last reply
    0
    • S Offline
      S Offline
      spode
      wrote on last edited by
      #3

      i will use "Other options are using a QStringList or a QList<QObject> as the model.", but the problem is: how to pass this qlist to this QML file?
      main.qml
      @
      Rectangle {
      width: 500; height: 500; signal emitsignal();
      Component { id: delegate_grafica; Rectangle { width: 300; height: 30; color: "orange"; border.width: 1; border.color: "yellow"; Text { color: "black"; text: deutschesWort; font.pixelSize: 15; anchors.centerIn: parent } } }
      ListView { id: list_parolaSalvate; x: 0; y: 0; width: 300; height: 300; delegate: delegate_grafica; model: emitsignal() }
      }
      @
      here i need a model, that i want to obtain from emitsignal, by which i would to obtain a qlist that is then the container of the model of my listview {}. my qlist will contain qlist<biglietto>
      where biglietto is:
      @
      biglietto::biglietto(QString newcolor, int newnumberm, bool important){
      QString color = newcolor;
      int number = newnumber;
      bool isImportant = important;
      etc.
      }
      @
      however, thank yoU!

      1 Reply Last reply
      0
      • S Offline
        S Offline
        srikanth_trulyit
        wrote on last edited by
        #4

        @ QDeclarativeContext* context = declarativeView.rootContext();
        context->setContextProperty("mymodel",(QObject*)&myModel); // here myModel is the QObject that exposes your model
        @

        @
        MyModel: public QObject {
        ...
        Q_INVOKABLE QStringList dataModel();
        }
        @

        In Qml
        @
        ListView {
        ...
        model: myModel.dataModel();
        }
        @

        1 Reply Last reply
        0
        • R Offline
          R Offline
          raja26
          wrote on last edited by
          #5

          But still how can I access the model data in delegate?

          1 Reply Last reply
          0
          • S Offline
            S Offline
            spode
            wrote on last edited by
            #6

            You need to write in the delegate the name of a public variable contained in the model, which you associate with QDeclarativeView.contextProperty.setContextProperty(nameOfTheModel, listThatyouhavemade). Note the you have to use first that I have just written and then set the source of the qml file where the model is needed.

            1 Reply Last reply
            0
            • R Offline
              R Offline
              raja26
              wrote on last edited by
              #7

              I found that a simple @modelData@ in the delegate does it for QStringList.
              [quote author="spode" date="1345319889"]You need to write in the delegate the name of a public variable contained in the model, which you associate with QDeclarativeView.contextProperty.setContextProperty(nameOfTheModel, listThatyouhavemade). Note the you have to use first that I have just written and then set the source of the qml file where the model is needed.[/quote]

              1 Reply Last reply
              0
              • S Offline
                S Offline
                spode
                wrote on last edited by
                #8

                I have not understood. could you please explain youself better?

                1 Reply Last reply
                0
                • R Offline
                  R Offline
                  raja26
                  wrote on last edited by
                  #9

                  To access the list of @QString@ in that QStringList I have used @modelData.

                  Like this:

                  ListView {
                  model: stringListPassedFromCpp
                  delegate: Text {
                  text: modelData
                  }
                  }@

                  1 Reply Last reply
                  0
                  • S Offline
                    S Offline
                    spode
                    wrote on last edited by
                    #10

                    I do not understand..

                    1 Reply Last reply
                    0
                    • R Offline
                      R Offline
                      raja26
                      wrote on last edited by
                      #11

                      Look at my above code. The 'modelData' gives the QString stored in QStringList. So that I can use 'modelData' to access the QString stored inside the QStrlingList.

                      I have used QStringList as the model for QML ListView. Have you understood now?

                      1 Reply Last reply
                      0
                      • S Offline
                        S Offline
                        spode
                        wrote on last edited by
                        #12

                        Ok. Now i have understood! :)

                        1 Reply Last reply
                        0
                        • R Offline
                          R Offline
                          raja26
                          wrote on last edited by
                          #13

                          @spode: My pleasure.. :-)

                          1 Reply Last reply
                          0
                          • J Offline
                            J Offline
                            joonne
                            wrote on last edited by
                            #14

                            Hi, I am trying to do almost same thing as mentioned here but I don't understand what modelData means here:

                            @ListView {
                            model: stringListPassedFromCpp
                            delegate: Text {
                            text: modelData
                            }
                            }@

                            How and where should I declare this modelData ? Thanks in advance. :)

                            I could ask something more and accurate about this too:

                            I have now QStringList for testing purposes which has 3 strings and I would like to get this QStringList to qml. I would like to use TextSwitch as delegate. This is what I have at the moment:

                            @SilicaListView {

                                    anchors.fill: parent
                                    model: model_.excerciseNames()
                            
                                    delegate: TextSwitch {
                            
                                        text: 
                                        onClicked: {}
                                    }
                                }
                            

                            }@

                            The function excerciseNames() is defined as

                            @Q_INVOKABLE QStringList excerciseNames();@

                            I think I am yet very far from the solution so any help would be great :D

                            1 Reply Last reply
                            0
                            • R Offline
                              R Offline
                              raja26
                              wrote on last edited by
                              #15

                              joone
                              Read about modelData in this link "QStringList to QML":https://qt-project.org/doc/qt-5.0/qtquick/qtquick-modelviewsdata-cppmodels.html#qstringlist-based-model

                              So all the QString within the QStringList will can be accessed as modelData

                              So you can access the QString data in the TextSwitch delegate as

                              @SilicaListView {
                              anchors.fill: parent
                              model: model_.excerciseNames()

                              delegate: TextSwitch {
                              text: modelData
                              onClicked: {}
                              }
                              }@

                              1 Reply Last reply
                              0
                              • J Offline
                                J Offline
                                joonne
                                wrote on last edited by
                                #16

                                The examples in that page you pointed me are invisible for me, can someone see whats in there? I tried to solve this from the Qt-Creator examples also but didn't get it to work yet. When I use the Q_INVOKABLE method with QStringList I get one of the Strings from the list but when I try to do as the example refered and use this :

                                @context>setContextProperty("excerciseNamesModel",QVariant::fromValue(model->excerciseNames()));

                                SilicaListView {
                                anchors.fill: parent
                                model: excerciseNamesModel

                                delegate: TextSwitch {
                                text: modelData
                                onClicked: {}
                                }
                                }
                                @

                                then I don't get anything. The registered excerciseNamesModel is coloured in the editor so it apparently recognizes the model but it is not working for some reason.

                                1 Reply Last reply
                                0
                                • R Offline
                                  R Offline
                                  raja26
                                  wrote on last edited by
                                  #17

                                  @Q_INVOKABLE@

                                  means the the method can be called from the QML side. So you have to set your cpp model object as
                                  @
                                  ExcerciseNamesModel namesModel;
                                  auto context = viewer.rootContext();
                                  context->setContextProperty("excerciseNamesModel", namesModel)@

                                  and then set the model in QML file as
                                  @
                                  SilicaListView {
                                  anchors.fill: parent
                                  model: excerciseNamesModel.excerciseNames()

                                  delegate: TextSwitch {
                                  text: modelData
                                  onClicked: {}
                                  }
                                  }@

                                  Note: This code is just like pseudocode and I didn't compile it or test it.

                                  1 Reply Last reply
                                  0
                                  • R Offline
                                    R Offline
                                    raja26
                                    wrote on last edited by
                                    #18

                                    You can read more about Exposing CPP models to QML in this link "Link":http://qt-project.org/doc/qt-4.8/qdeclarativemodels.html#qstringlist-based-model

                                    1 Reply Last reply
                                    0
                                    • J Offline
                                      J Offline
                                      joonne
                                      wrote on last edited by
                                      #19

                                      Okay thanks, I will try to figure this out. :)

                                      1 Reply Last reply
                                      0
                                      • J Offline
                                        J Offline
                                        joonne
                                        wrote on last edited by
                                        #20

                                        Would you happen to know a solution for my other problem also ? After updating this Sailfish SDK to a newer version, I lost qDebug() prints and I haven't found where they would come back. I can't see them at the application output view anymore and this makes it a lot harder to track down the behaviour of my program. :D

                                        1 Reply Last reply
                                        0
                                        • J Offline
                                          J Offline
                                          joonne
                                          wrote on last edited by
                                          #21

                                          Ok I realised something, I had to use setContextProperty function again to update the excerciseNamesModel and I passed the variable context to my actual model class and now everything works. Thank you for the 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