Pass data from C++ to qml using signals to update charts at runtime

SaranshVora

Hello,
I want to pass data from C++ file to qml file for line series at runtime without using timer. ```
//CPP (I am calling the function qmlregistertype for this class in another .cpp file)
``
class GraphicalDisplayItem : public QObject
{
Q_OBJECT
Q_PROPERTY(double dataReadX READ dataReadX NOTIFY dataChanged)
Q_PROPERTY(double dataReadY READ dataReadY NOTIFY dataChanged)

public:
	explicit GraphicalDisplayItem(QObject *parent = 0);
	~GraphicalDisplayItem();

	double dataReadX();
	double dataReadY();
	void updateData(double value);
	

Q_SIGNALS:
    void dataChanged();

// definitions of dataReadX and update data
double GraphicalDisplayItem::dataReadX()
{
static int i = 0;
return x.at(++i);
}

void GraphicalDisplayItem::updateData(double value)
{
x.push_back(x_limit++);
y.push_back(value);
start = true;
dataChanged();// based on this signal call I want to update the data in the charts how can I do that ?
}

//QML :
```Item {
    id: valueDisp

    implicitWidth: 640
    implicitHeight: 640
    property int currentIndex: 0
    property int j: 0;
    property int position:0;
    property double datax:0;
    property double datay:0;

    ChartView {
           id:chartView
            title: "Data Output"
            anchors.fill: parent
            legend.visible: false
            antialiasing: true

            MouseArea {
                       anchors.fill: parent
                      // onClicked: {

                                      }

            ValueAxis {
                id: axisX
               // title:"iterations"
                min:0
                max:100
                tickCount: 9

            }

            ValueAxis {
                id: axisY
               // title:"Value"
                min: 0
                max: 100
                tickCount: 1

                }

            LineSeries {

                        id:lineSeries
                        name:"Data Output"
                        axisX:axisX
                        axisY:axisY
                        useOpenGL: true
                          }

 }
    GraphicalDisplayItem{
       onDataChanged:
   {

                             lineSeries.append(componentData.dataReadX , componentData.dataReadY)
    }
     }
}