How to set Value Axis Label Format on QML from milliseconds to mm:ss?

[emmericatto]

Background

I am using QtCreator and I have a file called myScopeView.qml, which represents a scope view similar to the example provided here.

In myScopeView.qml, there is a ChartView that is updated every second with a timer so the plot changes values on X axis and Y axis.

X axis represents time expressed in milliseconds (integer values), because of the data acquisition, and Y axis represents voltage values (characterized as integer values).

Problem

The plot shows X axis values as integer, i.e. 123456789, but I would like to visualize the corresponding mm:ss value, i.e. 20:34. I think I have to modify the value of labelFormat.

ValueAxis{
    id: axisX
    min: 0
    max: 0
    tickCount: 5
    labelFormat: // I don't know what I have to set here
    }

Question

Is it possible to set a specific value in labelFormat in order to have mm:ss visualized?

Notes

Instead of the modification of labelFormat I tried to use a Javascript function for the conversion but this solution does not work because the conversion is achieved before the visualization and so the plot shows nothing because there is no Y values associated to new X values. That's why I am asking for a labelFormat command, but I will appreciate also a Javascript hint.

I know that QML QtCharts has QDateTimeAxis which provides mm:ss format but I would like to convert data only for the visualization and not for other purposes.