My chart is not scaling with YAxisDragModifier

Hi Ivan

In this demo the YAxis is declared with AutoRange = EAutoRange.Always. See Line #60 in the source code

// Create a NumericAxis on the YAxis with 2 Decimal Places
sciChartSurface.yAxes.add(
    new NumericAxis(wasmContext, {
        growBy: new NumberRange(0.1, 0.1),
        labelFormat: ENumericFormat.Decimal,
        labelPrecision: 2,
        labelPrefix: "$",
        autoRange: EAutoRange.Always
    })
);

AutoRange.Always means ‘always autorange, always, to fit the data, always’ – even if you put modifiers like YAxisDragModifier on the chart

How to handle the ability to autorange (fit new data) while allowing scrolling or panning of an axis? You need a way to toggle between the two modes.

Simple solution

The simple solution is to set yAxis.autoRange = EAutoRange.Once. This will fit the data once on startup. Also when changing the data on the chart, call sciChartSurface.zoomExtents() to manually fit the data.

Better / but more Complex Solution

A better solution would be to toggle between the two modes. Consider how TradingView does this.

1. When the chart starts up, it is in yAxis.autoRange = EAutoRange.Always mode
2. When the user mouse-down on the yAxis, you set yAxis.autoRange = EAutoRange.Never, allowing the yAxis drag to work. Here is how to detect mouse-down on axis.
3. The user must then click a button to re-enable auto ranging on the Y-Axis by setting yAxis.autoRange = EAutoRange.Always again

Let me know if this helps

Best regards
Andrew