Category: JavaScript

I am trying to implement the following functionality requested by our users:

Zoom:
– Only zoom the chart when using CTRL + MouseWheel key
– This is similar to how most browsers behave

Pan/Scroll:
– If no CTRL key is pressed, then pan/scroll
– This is similar to how most browsers behave

Given the above requirement, I started by creating custom modifier by extending YAxisDragModifier.

My code almost works:
– When using CTRL + Mouse Left & Drag, it Scales (zooms) — just like the user wants
– But using CTRL + Mouse Wheel does not do the same — it only Scales (Zooms).

I have uploaded the code at codesandbox.io:
https://codesandbox.io/s/amazing-shape-2ispt0?file=/src/customModifiers.ts

Note that I have not tried to implement this in ZoomPanModifier yet, but would be helpful if you could give me some pointers on getting this feature in there too.

I would appreciate any help I can get and thanks a bunch in advance.

Best Regards,
Sachin Patel.

Hello All,

Is there a way to have a cursor modifier display on a mouse left/center/right click instead of automatically showing when the mouse is over the chart? I tried setting the ExecuteOn property but had no effect.

Thanks in advance,
Sergio.

I’m a C# developer looking to evaluate working with SciChartJS for a possible future project.

I’ve created a .NET Blazor Project working with JavaScript Interop and I would like to extend the CustomChartModifier2D in TypeScript.

I’ve not used npm to install SciChart into the project, rather I’m using the CDN approach in my _Host.cshtml file.

<script src="https://cdn.jsdelivr.net/npm/[email protected]/index.min.js" crossorigin="anonymous"></script>

I’ve been searching online for a SciChartJS TypeScript definition file so that I can leverage TS Strongly Typed system in my test project.

Is there one? Or do I need to build my own, or even is there an already made example of extending SciChart with TypeScript somewhere I’ve missed?

Thank you

Hi,

In my application I am using two charts for represent different values. I am using LegendModifier on the first chart. Is it possible when i uncheck the series on first chart and the same color series on second chart also need to hide from the second chart. Any event callback function available in LegendModifier ?

Good afternoon. My team and I are looking at your library to create a depth chart, like here, but have run into a few problems:
1. if we have, for example, a “buySeries” array larger than the “sellSeries” array, the graph is not drawn very nicely.
2. the labels are not drawn correctly when we have too small numbers, I tried to solve the problem with xAxis.textFormatting = ‘0.#####’ or ‘0.00###’, but that doesn’t work for some reason.
3. If we want to add labels while hovering over the chart with showLabel = true , then we get 4 labels, two on yAxis. is it possible to make the buySeries label appear only on the left, for example, and the sellSeries label only on the right? (second screenshot)

Hello

My application environment is on the mobile browser, so we need to switch between [pan] and [rollover]

When I use a button to switch, everything is fine, but when I want to switch with a long press, an exception occurs

Below is my code

    initModifier() {
        this.partitionList.forEach((obj, idx)=>{
            let sciChartSurface = this.sciObj[idx].sciChartSurface;
            this.zoomPanModifier[idx] = new ZoomPanModifier();
            this.rolloverModifier[idx] = new RolloverModifier({modifierGroup: this.modifierGroupId, showTooltip: false});
            this.zoomPanModifier[idx].isEnabled = true;
            // 擴增功能
            sciChartSurface.chartModifiers.add(
                this.zoomPanModifier[idx],
                new ZoomExtentsModifier(),
                new MouseWheelZoomModifier(),
                new PinchZoomModifier(),
            );
        });
    },
    switchCross() {
        let enablePan = !this.zoomPanModifier[0].isEnabled;
        this.partitionList.forEach((obj, idx)=>{
            let sciChartSurface = this.sciObj[idx].sciChartSurface;
            this.zoomPanModifier[idx].isEnabled = enablePan;
            if (enablePan)
                sciChartSurface.chartModifiers.removeAt(4);
            else
                sciChartSurface.chartModifiers.add(this.rolloverModifier[idx]);
        });
    },

I recorded a video, first use the button to switch, and then long press to switch, you can see the problem I want to narrate from the video, the URL is as follows: https://youtu.be/vJjbLNGS-iM

After the problem occurred, it was expected that touchmove should be [pan], but it became [zoom]

Thanks for your help

Hello,

We have a heatmap where we can zoom in using the MouseWheelZoomModifier. Essentially we want to stop zooming at a certain visibleRange level and we cannot achieve it. Currently we have a heatmap that’s about 1500 pixels in width (with 1500 datapoints, 1-to-1), but the user can zoom so far you essentially see just 1 data point spread over the 1500 pixels.

We want to be able to zoom, but up to a certain limit, let’s say 100 datapoints visible. When visibleRange.max – visibleRange.min <= 100 we want to stop zooming.

We’ve tried suspendUpdates() and manually setting the visibleRange, but this doesn’t produce the desired results because suspendUpdates stops everything (including zooming out again) and resetting visibleRange solves it for a second, but the user is able to zoom in again. We also tried a custom mouseWheelModifier class and just removing the zoom in functionality at the treshold but that does not seem to work because scichart gives an error of having different mouseWheelModifiers.

I hope that this problem was expressed sufficiently. Please let us know if you have any questions.

Is it possible, in version 2.2.2404, to have RubberBandXyZoomModifier function like what seems to be the default for v3? So when I’m dragging the box to zoom, if I leave the chart area, the box snaps to the edges of the chart, and upon mouse release, it zooms normally to the box.

I can provide an example:

https://8tunzo.csb.app/ — broken (version 2.2.2404)

https://umvryi.csb.app/ — working (version 3.0.301)

Same exact code

import { SciChartSurface } from "scichart/Charting/Visuals/SciChartSurface";
import { NumericAxis } from "scichart/Charting/Visuals/Axis/NumericAxis";
import { XyDataSeries } from "scichart/Charting/Model/XyDataSeries";
import { FastLineRenderableSeries } from "scichart/Charting/Visuals/RenderableSeries/FastLineRenderableSeries";
import { MouseWheelZoomModifier } from "scichart/Charting/ChartModifiers/MouseWheelZoomModifier";
import { RubberBandXyZoomModifier } from "scichart/Charting/ChartModifiers/RubberBandXyZoomModifier";
import { ZoomExtentsModifier } from "scichart/Charting/ChartModifiers/ZoomExtentsModifier";

const dataX = [0, 10, 20, 30, 40, 50];
const dataY = [0, 10, 5, 20, 15, 35];

// eslint-disable-next-line
SciChartSurface.useWasmFromCDN();

async function initSciChart() {
  const { sciChartSurface, wasmContext } = await SciChartSurface.create(
    "scichart-root"
  );

  const xAxis = new NumericAxis(wasmContext);
  const yAxis = new NumericAxis(wasmContext);
  sciChartSurface.xAxes.add(xAxis);
  sciChartSurface.yAxes.add(yAxis);

  const lineData = new XyDataSeries(wasmContext, {
    xValues: dataX,
    yValues: dataY
  });

  sciChartSurface.renderableSeries.add(
    new FastLineRenderableSeries(wasmContext, { dataSeries: lineData })
  );

  sciChartSurface.chartModifiers.add(new MouseWheelZoomModifier({}));
  sciChartSurface.chartModifiers.add(new RubberBandXyZoomModifier({}));
  sciChartSurface.chartModifiers.add(new ZoomExtentsModifier({}));
}

initSciChart();

I added the cursor modifier as below:

const chartDefinition = {
    ......,
    modifiers: [
        { 
            type: EChart2DModifierType.Cursor, 
            options: { crosshairStroke: "green",  crosshairStrokeThickness: 1}  
    },
    { type: EChart2DModifierType.MouseWheelZoom },
    { type: EChart2DModifierType.ZoomExtents }
    ]
};

const { sciChartSurface, wasmContext } = await chartBuilder.build2DChart("scichart-root", chartDefinition);  

As I want to show the x, y values of the cursor somewhere outside the chart instead of showing the tooltip. How can I get the x, y values when the cursor moving?

I have a live updating chart with multiple traces. After updated SciChart to v3.0.280, I got “Uncaught (in promise) RangeError: Maximum call stack size exceeded” error sometimes when I call XyDataSeries.appendRange(). This error will not be triggered if just initialize the chart and keeps updating the chart data. It seems happening after I modified the visibleRange of x-axis or y-axis. But the error is triggered on the line calling appendRange(). I have no clue for this issue. My codes didn’t change and only updated the SciChart version. Could you find the possible cause of my problem? Please refer to the attached screenshots.

Codes to update the chart data:

    UpdateSuspender.using(sciChartSurfaceRef.current, () => {
        console.time("Time - Update series");
        for (tnum=0; tnum<MAX_TRACE; tnum++) {
            traceObj = tracesInfoObj.current[tnum];
            if (traceSeries.current[tnum] && traceObj.status === "Active") {
                traceSeries.current[tnum]["xyDataSeries"].clear();
                switch (traceObj.type) {
                    case 0:
                        traceSeries.current[tnum]["xyDataSeries"].appendRange(dataX, newSpecData);
                        break;
                    case 1:
                        traceSeries.current[tnum]["xyDataSeries"].appendRange(dataX, newMaxHoldData);
                        break;
                    case 2:
                        traceSeries.current[tnum]["xyDataSeries"].appendRange(dataX, newMinHoldData);
                        break;
                    case 3:
                        traceSeries.current[tnum]["xyDataSeries"].appendRange(dataX, averageData);
                        break;
                }   
            }
        };
        console.timeEnd("Time - Update series");
    });

Hello All,

I was trying to set the visual range property on a numeric axis but i get the error that the “equals” is not a function of NumerixAxis. This happens when i try the following.

export function setXAxisVisibleRange(element, visibleRange) {
     const { sciChartSurface } = resolveContext(element);
     var axis = sciChartSurface.xAxes.get(0);
     axis.visibleRange = visibleRange; **//error here**
}

attached is a picture of a more detailed error. Ultimately what I am trying to do is to sync up the visual range of two charts x axis like in the following tutorial

https://www.scichart.com/documentation/js/current/webframe.html#Tutorial%2009%20-%20Linking%20Multiple%20Charts.html

Thanks for your help in advance.

UPDATE

So my issue was that I had a serialization issue with the NumberRange class. I can now sync up the charts just like in the tutorial. The problem now is that if I scroll or zoom very fast eventually the charts start to flicker in an endless loop. Has anyone ever seen this behavior? One thing I notice is that the min and max value have over 10 decimal points.

Here is a quick printout of the value change events between the two charts when the flickering starts.

Any ideas?

–> CH.1 Min: 0.532180460735786 Max: 3.457511660735786
–> CH.2 Min: -0.17488026755852848 Max: 4.339519732441472
–> CH.2 Min: 0.025927491638795958 Max: 4.088887491638796
–> CH.2 Min: 0.38738145819397996 Max: 3.63774945819398
–> CH.1 Min: 0.5319630448160535 Max: 3.4572942448160537
–> CH.2 Min: 0.532180460735786 Max: 3.457511660735786
–> CH.1 Min: -0.17488026755852848 Max: 4.339519732441472
–> CH.1 Min: 0.025927491638795958 Max: 4.088887491638796
–> CH.1 Min: 0.38738145819397996 Max: 3.63774945819398
–> CH.2 Min: 0.5319630448160535 Max: 3.4572942448160537
–> CH.1 Min: 0.532180460735786 Max: 3.457511660735786
–> CH.2 Min: -0.17488026755852848 Max: 4.339519732441472
–> CH.2 Min: 0.025927491638795958 Max: 4.088887491638796
–> CH.2 Min: 0.38738145819397996 Max: 3.63774945819398
–> CH.1 Min: 0.5319630448160535 Max: 3.4572942448160537
–> CH.2 Min: 0.532180460735786 Max: 3.457511660735786
–> CH.1 Min: -0.17488026755852848 Max: 4.339519732441472
–> CH.1 Min: 0.025927491638795958 Max: 4.088887491638796
–> CH.1 Min: 0.38738145819397996 Max: 3.63774945819398
–> CH.2 Min: 0.5319630448160535 Max: 3.4572942448160537
–> CH.1 Min: 0.532180460735786 Max: 3.457511660735786
–> CH.2 Min: -0.17488026755852848 Max: 4.339519732441472
–> CH.2 Min: 0.025927491638795958 Max: 4.088887491638796
–> CH.2 Min: 0.38738145819397996 Max: 3.63774945819398
–> CH.1 Min: 0.5319630448160535 Max: 3.4572942448160537
–> CH.2 Min: 0.532180460735786 Max: 3.457511660735786
–> CH.1 Min: -0.17488026755852848 Max: 4.339519732441472
–> CH.1 Min: 0.025927491638795958 Max: 4.088887491638796
–> CH.1 Min: 0.38738145819397996 Max: 3.63774945819398
–> CH.2 Min: 0.5319630448160535 Max: 3.4572942448160537
–> CH.1 Min: 0.532180460735786 Max: 3.457511660735786
–> CH.2 Min: -0.17488026755852848 Max: 4.339519732441472

I have a real time updated chart and users can add annotation to the chart. The position of the annotation will be updated with the chart data. I would like to stop updating the annotation position while user dragging the annotation. So I added a flag (e.g. isDragging) to the annotation dragStarted and dragEnded events. The isDragging flag will be set to true in dragStarted and then set to false in dragEnded. I will check this flag before updating the annotation position.

Here’s the problem, the annotation dragStarted event will be triggered when users do panning in the chart. But the dragEnded will not be triggered in this case. It breaks my plan to stop updating the annotation position as the isDragging will be incorrect. Is it a bug that the annotation dragStarted event (but not the dragEnded event) triggered when panning?

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.

I have a simple need to display a horizontal heatmap based on values along the x-axis. So if value on x-axis is 1, color shown on the heatmap should be orange, if the next value is 2, red color bar appears to next the previous orange etc. Something like this (see attached graphic also):

Heatmap: [=orange=red=green]
values along x-axis: [22.05, 24.00, 30.00 ]

So the code I am trying is as follows:

export async function renderHeatMap(element) 
{
    const { sciChartSurface, wasmContext } = await SciChartSurface.create(element);

    sciChartSurface.xAxes.add(new NumericAxis(wasmContext));
    sciChartSurface.yAxes.add(new NumericAxis(wasmContext));

    var heatMapData = zeroArray2D([1, 5]);
    heatMapData[0][0] = 22.05; //should appear as color1 in heatmap
    heatMapData[0][1] = 24.00; //...
    heatMapData[0][2] = 30.00; //should appear as color2 in heatmap
    heatMapData[0][3] = 26.75;
    heatMapData[0][4] = 30.00; //should appear as color3 in heatmap

    const heatmapDataSeries = new UniformHeatmapDataSeries(wasmContext, 0, 1, 0, 1, heatMapData);

    const heatmapSeries = new UniformHeatmapRenderableSeries(wasmContext, {
        dataSeries: heatmapDataSeries,
        colorMap: new HeatmapColorMap({
            minimum: 20, // min value in the zValues (data) to map to offset 0 in the colormap
            maximum: 30, // max value in the zValues (data) to map to offset 1 in the colormap
            gradientStops: [
                { offset: 0, color: "#00008B" },
                { offset: 0.3, color: "#7FFF00" },
                { offset: 0.7, color: "#FFFF00" },
                { offset: 1.0, color: "#FF0000" },
            ],
        }),
    });

    sciChartSurface.renderableSeries.add(heatmapSeries);
}

But this only displays an empty grid. I don’t see a heatmap. Anyone can point out what may be wrong? Not even the axis is showing up correctly.

I am using SciChartSurface.create() to create chart and it works well. However, I got the webGL memory issue randomly – WebGL memory issue. I am trying to apply a workaround to use SciChartSurface.createSinge() instead. The createSingle() function doesn’t work for me, the chart cannot be rendered.

const { sciChartSurface, wasmContext } = await SciChartSurface.createSinlge(`${chartId}-chart-root`, { theme: themeObj });

There is no error showing in the developer tool console. I have no idea what’s wrong.

I have a top chart that is a heatmap and there is another bottom chart that is a temperature map. I want the heatmap not show any y-axis labels but still keep the x-axis start aligned from the left side. I tried turning off the y-axis lables (which I do not need in the heatmap), but that moves the heatmap to the left and not kept aligned with the bottom chart.

const yAxis = new NumericAxis(wasmContext, {
autoRange: EAutoRange.Always,
labelFormat: ENumericFormat.Decimal,
labelPrecision: 2,
labelPostfix: "C",
drawLabels: false
});
The above code hides the y-axis labels but also removes the space on the left side so the x-axis of both graphs does not remained aligned. I need a way to somehow keep the start of x-axis aligned for both top and bottom graphs.

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?

Hello,

I am currently developing an application using Electron (v. 8.3.0), React (v. 17.0.1), and TypeScript (v. 4.0.5). I have created a simple demo app (see attached) to test this software, and I found that whenever the application window is resized, there is an “Uncaught null” error from scichart2d.js caught by the console. I also found that at some window dimensions, it even seems that the chart cannot properly be displayed and it will try to constantly rerender, quickly filling up the console with the same error.

A couple of notes:

• I currently am using a trial key.
• I am compiling this application using electron-webpack (https://webpack.electron.build/). It has a few built-in tools that ease the compilation/app creation process when combining Electron with other frameworks. This means some of the webpack API being used is abstracted, but we can append our own (see webpack.renderer.additions.js), more information can also be found at https://webpack.electron.build/modifying-webpack-configurations.
• Electron v. 8.3.0 uses Chromium 80, so all features should be supported.

I’m trying to add an AxisMarkerAnnotations for some line series on my chart.

I was following these questions answered here:
https://www.scichart.com/questions/js/adding-axis-markers-to-fastlinerenderableseries
https://www.scichart.com/questions/js/price-indicators-on-yaxis

I managed to render the axis marker for my series. Now I’m trying to the set the Y value of the marker annotation as the value where the line intersects the Y Axis.
I want the marker value to be the last value of the series, only if the xAxis.visibleRange.max > series.XdataRange.max.

The two attached images show the desired feature.
One shows the marker annotation with the Y1 being the one where the line intersects the YAxis.
The other shows the marker annotation with the Y1 being the last value of the line, because it is visible.

I read some answers here on the forum about using the HitTest API to do this, but I couldn’t make it work on my JS app

Hi,

We use SciChart extensively in our WPF applications and make use of CustomRenderableSeries, writing all kinds of different lines and bitmaps directly to the IRenderContext2D depending on the point metadata.

We’re now looking at doing something similar in JavaScript, but can’t find any examples of this kind of customisation in the documentation. In the JavaScript library, is it possible to draw directly to a ‘canvas’ in the same way as in the WPF version? If so, could you please point to an example?

Many thanks,

Graham.

Hello,

I want to render a base64 image in ScichartJS without actually rendering it in DOM. I saw that you have these guides in WPF:
https://support.scichart.com/index.php?/Knowledgebase/Article/View/17213/34/
https://www.scichart.com/documentation/win/current/webframe.html#Screenshots,_Printing_and_Export_to_XPS.html

However it is difficult to achieve it in Typescript. Is there a guide or any ideas on how to do it? I would appreciate any answer.

Hello,

Can you show this example(https://codepen.io/PodaRocheK/pen/yLGxGEL?editors=0011) and tell me, why metadata labels are not displayed in some cases? May be you can tell me how to do it correctly? A have similar chart with a lot of datapoints and can’t understand why labels show only in some time(20s or > 1m after start the chart)

Thank you!

I recently upgraded SciChart from version 2 to version 3.0.266. It was working fine. But I got error (please refer to the attached screenshot) when I try to run my application today. It’s so strange as it worked fine yesterday and I didn’t make any codes change today.

Working on an application that requires toggling between Linear and Logarithmic scales. I am using the JavaScript version of the library, and I see that there is a LogarithmicNumericAxis available in the WPF version but there is not one currently supported in the JS version.

Curious if there were any recommendations on how to go about hand rolling this type of functionality?

The application is doing realtime streaming of data points so need to be able to update existing values as well as handle incoming values.