Category: JavaScript

When using AutoRange.Once on an axis, I expect the auto ranging to be done exactly once.
If at some point, I change the visible range to match the default one (0 to 10 for numeric axis), the auto range is triggered again.

Happens more if I provide inputs so the user can define a range, and depending on the use case, 0 to 10 is not that uncommon.
Kind of an edge case, but still something that can happen, and is definitely unexpected.

This can be seen happening here https://codepen.io/jrfv/full/xxeqwOd

I am considering applying server-side licensing for my javerScript application.

In the document below, there is a phrase “Our server-side licensing component is written in C++.”
(https://support.scichart.com/index.php?/Knowledgebase/Article/View/17256/42/)

However, there is only asp.net sample code on the provided github.
(https://github.com/ABTSoftware/SciChart.JS.Examples/tree/master/Sandbox/demo-dotnet-server-licensing)

I wonder if there is a sample code implemented in C++ for server-side licensing.

Can you provide c++ sample code?
Also, are there any examples to run on Ubuntu?

We managed to create a functioning chart, but sometimes when we first ran the chart it produced this error, followed by the chart being completely unable to display.

We attached the error message produced in DevTools, the expected outcome and the actual outcome when the error occurred.

I am considering applying server-side licensing for my javerScript application.

In the document below, there is a phrase “Our server-side licensing component is written in C++.”
(https://support.scichart.com/index.php?/Knowledgebase/Article/View/17256/42/)

However, there is only asp.net sample code on the provided github.
(https://github.com/ABTSoftware/SciChart.JS.Examples/tree/master/Sandbox/demo-dotnet-server-licensing)

I wonder if there is a sample code implemented in C++ for server-side licensing.

Can you provide c++ sample code?
Also, are there any examples to run on Ubuntu?

I am considering applying server-side licensing for my javerScript application.

In the document below, there is a phrase “Our server-side licensing component is written in C++.”
(https://support.scichart.com/support/solutions/articles/101000515345-scichart-js-domain-licensing-faq)

However, there is only asp.net sample code on the provided github.
(https://github.com/ABTSoftware/SciChart.JS.Examples/tree/master/Sandbox/demo-dotnet-server-licensing)

I wonder if there is a sample code implemented in C++ for server-side licensing.

Can you provide c++ sample code?
Also, are there any examples to run on Ubuntu?

There seems to be no documentation on how to configure scichart when using app router with nextJS, and I am running into an error.

I have followed a combination of this tutorial, and additional setup for nextJS found here, specifically the next.config.js file, copy-files-from-to.json, and additions to package.json. But I continue to get the error: ‘Module has already been declared’. (first/second pics in PDF)

I have attached a photos inside the pdf, including my project structure, and a zip with the files to duplicate.

Steps to replicate:
1) extract files and add root package.json to a directory of your choice
2) from within this directory, use ‘yarn create next-app scichart-prototype’ (use set-up options from 4th image in PDF)
3) Replace root layout.tsx and page.tsx with files in zip, add SciChartDemo directory and add page.tsx from that (also in zip)
4) replace the next.config.mjs file with the next.config.mjs file from the zip
5) add the copy-files-from-to.json from the zip
6) replace the package.json file in scichart-prototype directory with file from the zip.
7) run ‘yarn install’ to add packages
8) run ‘turbo dev’
9) after visiting localhost:3000/ click the Sci Chart Demo link to see error.

Thanks for taking a look.

question posted to nextjs forum

When using FastCandlestickRenderableSeries, I want every value to appear on the chart. I tried to use DataLabelProvider for this, but it didn’t work. What can I do.

class CustomDataLabelProvider extends DataLabelProvider {
onDataPoint(renderableSeries, xValue, yValue) {
    const labelText = `${yValue.toFixed(2)}`;

    const label = document.createElement('div');
    label.textContent = labelText;
    label.style.position = 'absolute';
    label.style.color = 'black';
    label.style.fontSize = '12px';
    label.style.left = `${this.parentSurface.coordinateCalculator.getCoordinateFrom(xValue) - label.clientWidth / 2}px`;
    label.style.top = `${this.parentSurface.coordinateCalculator.getCoordinateFrom(yValue) - label.clientHeight}px`;

    this.parentSurface.annotationCanvas.appendChild(label);
  }
}



const { sciChartSurface, wasmContext } = await SciChartSurface.create("scichart-root", {
theme: new SciChartJSLightTheme(),   
titleStyle: { fontSize: 22 },
 });

sciChartSurface.applyTheme(new SciChartJSLightTheme());
sciChartSurface.xAxes.add(new NumericAxis(wasmContext));
sciChartSurface.yAxes.add(new NumericAxis(wasmContext));
const yAxis = sciChartSurface.yAxes.get(0);
yAxis.visibleRange = new NumberRange(LAL, UAL);
const xAxis = sciChartSurface.xAxes.get(0);
xAxis.visibleRange = new NumberRange(0, endBarIndex);

const dataSeries = new OhlcDataSeries(wasmContext, {
xValues: xValues,
openValues: compositeScanAverageArray,
highValues: yValues,
lowValues: compositeScanAverageArray,
closeValues: yValues,
});

sciChartSurface.renderableSeries.add(new FastCandlestickRenderableSeries(wasmContext, {
dataSeries: dataSeries,
strokeThickness: 1,
dataPointWidth: 0.5,
paletteProvider: new CustomPaletteProvider(),
dataLabelProvider: new CustomDataLabelProvider(),
 }));

I am trying to subscribe to Visible Range changes on a DateTimeNumericAxis, it is not working, am I doing something wrong?

Hello,

I switched from NumericAxis to DateTimeNumericAxis to view x axis labels in hh:mm format. It is definitely showing the labels in this format which is what I wanted, but for some reason it always show “Jan 1” in the first label. I simply want to show hh:mm labels based on the X values. One thing to now is that this is a live updating chart, not static data.

What am I missing? attached is a picture showing the issue and a picture with the DateTimeNumericAxis configuration.

Thanks.
Sergio.

Hello,

I am experiencing an issue with the BoxAnnotation in SciChart where the precision of the box’s boundaries does not accurately match the data points it is supposed to represent. When dynamically creating a BoxAnnotation to highlight a range of values on a chart, the upper boundary (y2) is set to match the maximum value within the specified range. Despite the calculation seeming accurate, the rendered annotation’s top edge is visually lower than the top of the highest column it encompasses, creating a slight discrepancy. In my application, I am creating a lot of charts, and this issue occurs only on charts with a big data range.

Environment:

SciChart Version: 3.2.532
Browser: Chrome

Attaching code snippet on jsfiddle:
https://jsfiddle.net/c9dekx6v/2/

Regards,
Dmytro

I have a React application showing a real time updated chart which works well when receives data from event-based WebSocket. Now I need to modify the app with a new data source. I have an aysnc function to get a batch of data in an interval.

kinesisReadInterval.current = setInterval(async () => {
        const recordsResponse = await kinesisRef.current.getRecords({ ShardIterator: shardIterator }).promise();
        recordsResponse.Records.forEach(record => {
            try {
                const dataObj = JSON.parse(record.Data.toString('utf-8'));
                spectrumAnalyzerRef.current.metaDataHandler(dataObj);
            } catch (jsonError) {
                spectrumAnalyzerRef.current.binaryDataHandler(record.Data.buffer);
            }
        });

        shardIterator = recordsResponse.NextShardIterator;

        if (!shardIterator || !kinesisConected.current) {
                clearInterval(intervalId); // Stop interval if conditions are not met
        }
    }, 1000);

The recordsResponse.Records contains a batch of records and I want to update the chart based on these records one by one. From my logs, I can see that the binaryDataHandler() which will call appendRange() ran successfully for each record. However, the chart only redraws for the last record of the recordsResponse.Records. I have tried to store the recordsResponse.Records in a state variable and loop to update the chart later, but still got the same result. I am not sure whether it’s chart related issue or React rendering issue. Do you have any idea?

The chart is only showing 3 of 4 Tooltips, is there a way to avoid this?

I have a chart with multiple series, left and right y-axes and one x-axis, some series are assign to left y-axis and some are right y-axis and they all have the same x-axis.

But there is one specific serie that need to be control on its own. I consider adding another y-axis either on the left or right axis, but the issue with that is that both the left and right axes are vertically stacked with some other y-axes. So, if I add another y-axis, it will just be stacked, but I need this y-axis to be on its own and not stacked.

The image below show my current chart, and the white line serie is the one that need a y-axis of its own. Currently it is attach to the right y-axis.

Hello scichart team!

We would like to run e2e tests for our application, which uses the scichirt.js library. To run e2e, we will be running a local development server with our SPA app in some CI environment.

Is there a way to avoid installing a license manager for e2e in CI env and use RuntimeLicenseKey, but for localhost?

We created a medical simulation similar to your demo: https://demo.scichart.com/javascript-vital-signs-ecg-medical-chart-example

We choose scichart (JS) as the app has to be high performant. In development (I’m working on a mac machine) everything is working great. Now in production I’m surprised, that most computers in our hospital can’t handle scichart, as it is running extremely slow (really slow motion).
I checked also your demo app, which also runs only in slow motion. So it seems not to be an application problem, but a scichart problem. On my development machines there is no problem with the demo.

The slow motion problem occurs on our iPads and on multiple windows machines (VM) with e.g. intel i5 processor.

Is there anything I can do to get scichart JS apps running?

Hi,
Is it possible to add the scrollbar in the chart. If the visibleRangeLimit is set is it possible to add the normal scrollbar in the side of the chart.

stack overflow link : https://stackoverflow.com/questions/77781766/reactjs-sweep-line-optimizing-scichartjs-performance-reusing-wasmcontext-for-m

I have a performance problem with scichartjs, when initializing about 40 charts/surfaces the rendering state drops to 5-10 frames per second.

I think it might be related to the fact that I run the create function each time and not reusing the wasmContext maybe?
but I am not sure how to reuse the wasmContext or what is the best performance for this kind of type

demo : https://9669tv.csb.app/

(sorry for the low quality of the Giff due to 2 MB max size of upload)

this is my init function

export const initScichart = async (divElementId) => {
  SciChartSurface.UseCommunityLicense();
  //console.log(divElementId.id);
  const { sciChartSurface, wasmContext } = await SciChartSurface.create(
    divElementId,
    {
      theme: new SciChartJsNavyTheme(),
    }
  );

  sciChartSurface.xAxes.add(
    new NumericAxis(wasmContext, {
      visibleRange: new NumberRange(0, 5),
    })
  );
  sciChartSurface.yAxes.add(
    new NumericAxis(wasmContext, {
      autoRange: EAutoRange.Always,
    })
  );

  const xyDataSeries = new XyDataSeries(wasmContext, {
    fifoCapacity: 220_000, // set fifoCapacity. Requires scichart.js v3.2 or later
    fifoSweeping: true,
    fifoSweepingGap: 2_200,
    containsNaN: false,
    isSorted: true,
  });

  sciChartSurface.renderableSeries.add(
    new FastLineRenderableSeries(wasmContext, {
      dataSeries: xyDataSeries,
      strokeThickness: 1,
      stroke: "#50C7E0",
    })
  );

  xyDataSeries.sciChartSurfaceToDelete = sciChartSurface;

  return xyDataSeries;
};

the reason I need the charts on different surfaces is that I need to wrap them in SortableJS (to be able to drag them across the website)

I’m trying to add rollover / tooltip to a chart, which uses sweeping. First, everything is working fine, but after updating the data over more then one page, the rollover is messing around with the data.

I created a codesandbox with the vitalsign demo: https://codesandbox.io/p/sandbox/javascript-vital-signs-ecg-medical-chart-example-forked-2zqcs3

First the rollover works great. Wait until the data is updated to the left side. Then you’ll see the messed up values and rollover points.

Error from chart in div instrument_candle_chart_2
RuntimeError: call_indirect to a signature that does not match (evaluating ‘invoker(fn, thisWired, arg0Wired, arg1Wired, arg2Wired, arg3Wired, arg4Wired, arg5Wired, arg6Wired, arg7Wired, arg8Wired)

error here: OhlcSeriesDrawingProvider.prototype.draw:

this.nativeDrawingProvider.DrawPointsVec(nativeContext, xDrawValues, openValues, highValues, lowValues, closeValues, renderPassData.xCoordinateCalculator.nativeCalculator, renderPassData.yCoordinateCalculator.nativeCalculator, this.args);

Imagine I have a chart with a RolloverModifier, such that I see the point marker, and also a CursorModifier so I see the axis labels with the exact value I’m hovering.
This chart has the axis title hidden, and also the labels hidden, so I can really only see them trough the CursorModifier axis labels.
Since the axis title and labels are hidden, the axis labels spawn inside the chart, and the point marker from the RolloverModifier may be drawn on top of the labels.

I’d like to properly control drawing order here, so my axis labels get prioritised.
Is there a way to do so?

Codepen example: https://codepen.io/jrfv/full/VwqVBdo

https://stackoverflow.com/questions/77752586/reactjs-sweep-line-demo-issue-with-multiple-surfaces-not-updating-simultaneousl

I need to make a demo of a sweep line with multiple surfaces with reactjs, but The problem is that when I choose to show more than 1 surface it only plays on the data on the latest created surface and stops drawing data on the old surfaces.

you can see the example here with the code: https://28zf6p.csb.app/

this is a GIF for the problem:
[in the stack overflow link]

note: the reason I need multiple surfaces is that I want to have the charts draggable with sortableJS to follow the design I got.

Hello everyone,

I have 2 HorizontalLineAnnotations on the chart as price indicators. Sometimes i need to add to some label more data on the second line of the text. You can see example of correct annotation’s label. How can i add ‘\n’ or ‘
‘ to the text for such result?

Thank you a lot!

Hi,

We found that the part of our project that uses scichart does not work correctly on iOS12, and then we tried to open a browser on iOS12 to the scichart javascript demo webpage, and found that it did not work.

What is the minimum iOS version supported by javscript scichart?

Hi,
I’m trying to implement a market footprint with SciChart framework, I mean is possible create like a plugin for implement in the framework?
My idea was set body color of all the candles invisible and than for every candle set two volume series in horizontal like in the image.

Dear Andrew,

As mentioned in the previous question. we are getting ready to implement a comprehensive annotation and labeling functionality to our application. Although I know how to add scalable custom-annotations (your team guided us with the implementation in the past), an important part of of annotation functionality is. ability to edit the annotations. But I am having trouble accessing and interacting the the annotations.

How can I access the svg polygon nodes from the custom annotation and drag and move them? I have attched a video to show the existing functionality.

https://youtu.be/AkysJ2R3TyE1

Best,
Pramod

Looking to try and “link” two timeseries charts when either one is zoomed. The link aspect would be updating the other chart to have the same visible range as the zoomed chart.

Each chart has its visibleRange property updated in response to separate socket events, that happen at similar intervals but different.

Originally, was hoping to have something similar to the onZoomExtents method that fires a callback that would allow me to grab the latest min/max of the visibleRangeProperty of the xAxes to then update the other chart.

Any suggestions on how I could go about doing this?

And if it is not clear what I am talking about I can provide some code snippets.