Questions

I am working on CreateMultiPaneStockChartFragment example. Sometimes after I refresh data and call surface.zoomExtents(), the chart does not zoom to fit but stays the same. Why is this? I can then manually zoom to extents by double tapping the chart.

This is my (simplified) fragment code (stemming from the example but optimized for my case of regular updating) below. updateChart() is called periodically every 10 sec.

@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    SciChartBuilder.init(getActivity());
    sciChartBuilder = SciChartBuilder.instance();
}

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

    surface = view.findViewById(R.id.priceChart);
    initChart();
}

private void initChart(){
    final DefaultLayoutManager layoutManager = new DefaultLayoutManager.Builder().setRightOuterAxesLayoutStrategy(new RightAlignedOuterVerticallyStackedYAxisLayoutStrategy()).build();
    surface.setLayoutManager(layoutManager);

    final CategoryDateAxis xAxis = sciChartBuilder.newCategoryDateAxis()
        .withLabelProvider(new TradeChartAxisLabelProviderDateTime())
        .withAutoRangeMode(AutoRange.Once)
        .build();
    xAxis.setMinimalZoomConstrain(10d); // minimum data points

    surface.getXAxes().add(xAxis);

    final NumericAxis yAxisPrice = sciChartBuilder.newNumericAxis()
        .withAxisId(PRICES)
        .withAutoRangeMode(AutoRange.Always)
        .withGrowBy(new DoubleRange(0.01d, 0.01d))
        .withLabelProvider(new NumericLabelProviderPrice(coinCurrency))
        .build();
    yAxisPrice.setMinimalZoomConstrain(0d);
    surface.getYAxes().add(yAxisPrice);

    // add axes for MACD, RSI, VOL..


    legendModifier = sciChartBuilder.newModifierGroup()
        .withLegendModifier().withShowCheckBoxes(false).withShowSeriesMarkers(false).build()
        .build();
    // surface.getChartModifiers().add(legendModifier); // this causes crash; add it after series are present

    interactionModifiers = sciChartBuilder.newModifierGroup()
        .withPinchZoomModifier().withReceiveHandledEvents(true).withXyDirection(Direction2D.XDirection).build()
        .withZoomPanModifier().withReceiveHandledEvents(true).withClipModeX(ClipMode.ClipAtExtents).build()
        .withZoomExtentsModifier().withReceiveHandledEvents(true).build()
        .build();
    surface.getChartModifiers().add(interactionModifiers);

    cursorModifier = sciChartBuilder.newModifierGroup()
        .withCursorModifier().build()
        .build();
    cursorModifier.setIsEnabled(false);
    surface.getChartModifiers().add(cursorModifier);
}

private void updateChart(int daysToShow) {
    final PriceSeries priceData = getData(daysToShow);

    surface.getRenderableSeries().clear();
    surface.getAnnotations().clear();

    // price chart
    final OhlcDataSeries<Date, Double> stockPrices = sciChartBuilder.newOhlcDataSeries(Date.class, Double.class).withSeriesName(getString(R.string.price)).build();
    stockPrices.append(series.getDateData(), series.getOpenData(), series.getHighData(), series.getLowData(), series.getCloseData());
    final BaseRenderableSeries seriesOHLCV = sciChartBuilder.newCandlestickSeries().withDataSeries(stockPrices).withSeriesInfoProvider(new CustomOHLCSeriesInfoProvider()).withYAxisId(PRICES).build();
    surface.getRenderableSeries().add(seriesOHLCV);

    surface.getAnnotations().add(sciChartBuilder.newAxisMarkerAnnotation().withY1(stockPrices.getYValues().get(stockPrices.getCount()-1)).withBackgroundColor(Color.WHITE).withFontStyle(12, Color.BLACK).withYAxisId(PRICES).build());

    // do the same for MACD, RSI, VOL ...

    if(!surface.getChartModifiers().contains(legendModifier))
        surface.getChartModifiers().add(legendModifier); // this causes crash if added before any series is present

    if(!silent) {
        Log.d("debug", "surface.zoomExtents()");
        surface.zoomExtents(); // sometimes this does not work
    }
}