Can't retroactively add points to ScatterSeries

OlivierD

Hi

I recently looked forward to the addition QtGraphs to QML and have been trying to create 2D scatter graph that updates during the runtime of my program. To test this, I simply wanted to see if I could add new points to my ScatterSeries by pressing a button as seen in the following code:

import QtQuick
import QtQuick.Controls 6.7
import QtQuick3D 6.7
import QtGraphs 6.7
import QtQuick.Window
import QtQuick.Layouts


Window {
    width: 1024
    height: 768
    visible: true

    Rectangle {
        id: rectangle
        anchors.fill: parent

        Rectangle {
            id: rectangle1
            x: 520
            y: 0
            width: 504
            height: 768
            color: "#000000"

            GraphsView {

                id: graphView
                visible: true
                anchors.fill: parent

                theme: GraphTheme {
                    readonly property color c1: "#DBEB00"
                    readonly property color c2: "#373F26"
                    readonly property color c3: Qt.lighter(c2, 1.5)
                    colorTheme: GraphTheme.ColorThemeDark
                    gridMajorBarsColor: c3
                    gridMinorBarsColor: c2
                    axisXMajorColor: c3
                    axisYMajorColor: c3
                    axisXMinorColor: c2
                    axisYMinorColor: c2
                    axisXLabelsColor: c1
                    axisYLabelsColor: c1
                }
                component Marker: Rectangle {
                    id: marker
                    width: 16
                    height: 16
                    color:"#ffffff"

                    radius: width * 0.5
                    border.width: 4
                    border.color: "#000000"

                }

                ScatterSeries {
                    id: scatterSeries
                    axisX: ValueAxis {
                        max: 5
                        tickInterval: 1
                        minorTickCount: 9
                        labelDecimals: 1
                    }
                    axisY: ValueAxis {
                        max: 10
                        tickInterval: 1
                        minorTickCount: 4
                        labelDecimals: 1
                    }
                    // width: 4
                    // selectable:true
                    // hoverable:true
                    pointMarker: Marker {}


                    XYPoint {
                        x: 0
                        y: 2
                    }

                    XYPoint {
                        x: 1
                        y: 1.2
                    }

                    XYPoint {
                        x: 2
                        y: 3.3

                    }

                    XYPoint {
                        x: 5
                        y: 2.1
                    }

                }
            }

        }

        Button {
            id: pointSpawn
            x: 212
            y: 312
            text: qsTr("Add Point")
            checked: false
            checkable: false
            highlighted: false
            flat: false
            Connections {
                target : pointSpawn
                onClicked: {
                    scatterSeries.append(5,6)
                }

            }
        }
    }

}

I thought I could this by just appending two real values to the QScatterSeries because it is an Q_invokable function according to the documentation. When I try to run however I get the following error:

TypeError: Property 'append' of object QScatterSeries(0x2354355f5f0) is not a function

I am not sure how to fix this. Am I somehow being connected to the wrong QScatterSeries or am I just doing something wrong in my code. Would really appreciate some advice on this.

Kind regards
Olivier

Bob64

I'm still using Qt 5 but I had a look at the doc and it seems to me that the API exposed to QML is more limited in QtGraphs than it was in QtCharts. The append method is available in the QXYSeries C++ implementation class but not in QML as far as I can see. You might need to write a function in some backend C++ code that you expose to QML. This function would accept a QXYSeries* and you will be able to access append in the function's C++ implementation. You will be able to pass your scatterSeries object to this function from QML and it will be received as a QXYSeries*.