Adding right axis in QtQuick ChartView changes also left axis

MarcW

Hi,

I want dynamically change LineSeries in a QML ChartView. I'm using Qt 5.7
For this purpose, I have a variable 'updateChart', which triggers the replacement of existing LineSeries, using removeAllSeries() and createSeries()

Sometimes, a LineSeries needs to be displayed using a secondary axis (right axis).
The ChartView createSeries() doesn't allow to assign a right axis to a LineSeries, and from the documentation I cannot find an alternative.

Additionally, you need to have already an axis before calling the createSeries method.
Therefor I have declared 3 axes (X, Y left, Y right) in the ChartView for using them in the createSeries call. The min/max values are modified in another view and kept in the 'chartContext'.
After creation, I change the axisY to axisYRight.

The problem is that my ChartView displays the same axis (min/max values) on both sides. When I change one of the minima/maxima, it updates to that last value, even mixing the minimum from the left axis with the maximum from the right axis.

How can I avoid this ?
Below is my (shortened) code :
chartContext and dataModel are C++ contexts

ChartView {
	id: linechart;
	anchors.fill: parent;
 
	property var updateChart: chartContext.updateChart;
 
	title: chartContext.chartTitle;
	antialiasing: true;
 
	ValueAxis {
		id: xAxis;
		min: chartContext.minXAxis;
		max: chartContext.maxXAxis;			
	}
	ValueAxis {
		id: yAxis;
		min: chartContext.minYAxis;
		max: chartContext.maxYAxis;
	}
	ValueAxis {
		id: yAxis2;
		min: chartContext.minYAxis2;
		max: chartContext.maxYAxis2;
	}
 
	onUpdateChartChanged: {
		linechart.removeAllSeries();
 
		for (var i = 0; i < dataModel.numberOfSeries; ++i) {			
			var lineSeries;
			if (dataModel.axisLocation(i) == "Right") {
				lineSeries = linechart.createSeries(ChartView.SeriesTypeLine, dataModel.getYLabel(i), xAxis);
				lineSeries.axisYRight = yAxis2;
			}
			else {
				lineSeries = linechart.createSeries(ChartView.SeriesTypeLine, dataModel.getYLabel(i), xAxis, yAxis);
			}
			var point;
			for (var j = 0; j < dataModel.getNumberOfDataPoints(i); ++j) { 
				point = lineSeries.append(dataModel.getXValue(i,j), dataModel.getYValue(i,j));
			}
			lineSeries.pointsVisible = true;			
		}
        }
}

Jose Ramon

I'm working with qt5.9 and I have the same problem. Do you have find any solution?