Abstract Protected _isFlag that is set whenever Panel or any scale is resized.
Will be handled before plot to update scale and trigger resize event just once per frame.
Readonly backgroundInterface for attaching listeners to user interaction events (click, pointerenter, etc.) on chart background.
// Example syntax
chart.background.addEventListener('click', (event) => {
console.log(event)
})
For syntax examples, refer to EventInterface. Available event keys are listed under LCJSInteractionEventMap
Please note that many chart types have a separate "series background" (area enclosed by axes), which has its own separate events. This is accessed via seriesBackground property.
Readonly coordsSelector for "client" Coordinate System.
This references the coordinate system used in HTML.
It starts at top left of the web page and is measured in pixels.
For example, { x: 100, y: 20 } corresponds to 100 pixels from left and 20 pixels from top.
JavaScript events are tracked and HTML elements are positioned in the client coordinate system.
This selector can be used for translating client coordinates to other coordinate systems and vice versa. For example, in order to:
See translateCoordinate for more detailed use case information and example usage.
Readonly coordsSelector for "relative" Coordinate System.
This coordinate system is relative to the bottom left corner of the Control (chart/dashboard/etc.), and is measured as pixels.
For example, { x: 100, y: 20 } corresponds to 100 pixels from left and 20 pixels from bottom.
This selector can be used for two purposes:
Positioning LCJS UI elements in pixels:
// Position UI element in pixels by supplying `Control.coordsRelative` as its positioning system.
const textBox = Control.addUIElement(UIElementBuilders.TextBox, Control.coordsRelative)
.setOrigin(UIOrigins.LeftBottom)
.setPosition({ x: 100, y: 20 })
Translations between coordinate systems:
Use with translateCoordinate method to translate coordinates from "relative" to another coordinate system.
Readonly engineInterface for end user API of the LCJS engine. It provides some useful capabilities over the area enclosed by a single LCJS context (which can be just a single chart, or a Dashboard with several charts).
Readonly titleInterface for attaching listeners to user interaction events (click, pointerenter, etc.) on chart title.
// Example syntax
chart.title.addEventListener('click', (event) => {
console.log(event)
})
For syntax examples, refer to EventInterface. Available event keys are listed under LCJSInteractionEventMap
Scale for panel area in percentages (0-100).
While it is not functionally equal to this, using coordsRelative coordinate system is preferred (more confidence for long term support).
Add manually controlled Cursor object. These have exactly same functions as built-in cursors but they can be freely controlled by application logic.
const cursor = chart.addCursor()
Styling works same as built-in cursors (e.g. setCursor).
Position is set using setPosition method and displayed content using setResultTable(table => table.setContent(...))
For more details, see Developer documentation > Features > Cursor > Manual cursors
Cursor object.
Builder for cursor. Can be used to tweak a handful of properties which can't be changed during runtime.
Add callback function to be triggered when specified event is fired.
// Example syntax
object.addEventListener('click', (event) => {
console.log(event)
})
Some classes also report extra information about the interacted object with the second parameter:
// Most series share information about interacted data point
series.addEventListener('click', (event, info) => {
console.log(info)
})
Optional third parameter allows registering event handlers that will automatically remove themselves after first trigger:
// Example this listener will only fire once
object.addEventListener('click', (event) => {})
Each class has its own list of supported events.
Some events are from HTML standard (click, pointerdown, etc.),
while others are own events from LightningChart JS (dispose, resize, etc.)
To find what events are available, you can try following:
TypeScript enabled, just write addEventListener and see what possible event types the IDE suggests. These APIs are strongly typed, and even the callback event will be correctly typed.K type parameter extends.Callback function that is triggered when event is fired.
Optional options: LCJSAddEventListenerOptionsOptional extra configuration options.
Add a legendbox.
Legendbox is a type of UI element, that floats inside the chart/component it is created inside. It can be freely moved around with user interactions, as well as positioned in application code.
The purpose of legendbox is to describe the series and other visual components of the chart, by displaying their names and colors. Hovering over a series' legendbox entry will highlight that series, and clicking on the entry will toggle that series' visibility.
Legendbox alignment:
Alignment of legendbox can be selected by supplying one of the available LegendBoxBuilders to addLegendBox:
// Default (vertical) LegendBox.
const legendBox = ChartXY.addLegendBox()
// Horizontal LegendBox.
const horizontalLegendBox = ChartXY.addLegendBox(LegendBoxBuilders.HorizontalLegendBox)
Custom Legendbox positioning:
By default LegendBoxes are placed on the right side, or bottom of the chart (depending on alignment).
A custom location can be configured with UIElement API:
Position coordinate system is specified when creating legendbox.
addLegendBox( LegendBoxBuilders.VerticalLegendBox )
// Position = [0, 100] as percentages.
.setPosition({ x: 50, y: 50 })
addLegendBox( LegendBoxBuilders.VerticalLegendBox, chart.coordsRelative )
// Position = pixels.
.setPosition({ x: 300, y: 100 })
addLegendBox( LegendBoxBuilders.VerticalLegendBox, { x: chartXY.getDefaultAxisX(), y: chartXY.getDefaultAxisY() } )
// Position = Axis values.
.setPosition({ x: 5, y: 5 })
LegendBox
LegendBoxBuilder. If omitted, VerticalLegendBox will be selected. Use LegendBoxBuilders for selection.
Optional parameter for altering the coordinate system used for positioning the LegendBox. Defaults to whole Chart in percentages [0, 100].
Add new Slice to the Pie Chart. The Slice will be automatically assigned an unique style (using SliceFillStylePalette), that will not be affected by sorting of Slices.
Currently there is no way to override the individual style of a Slice - style modifications must be done using the API of Pie Chart.
New Slice object.
Initial name for Slice as string.
Initial value for Slice as number.
Add a stand-alone UIElement using a builder.
Example usage:
addUIElement( UIElementBuilders.TextBox )
// Position = [0, 100] as percentages.
.setPosition({ x: 50, y: 50 })
addUIElement( UIElementBuilders.TextBox, chart.coordsRelative )
// Position = pixels.
.setPosition({ x: 300, y: 100 })
addUIElement( UIElementBuilders.TextBox, { x: chartXY.getDefaultAxisX(), y: chartXY.getDefaultAxisY() } )
// Position = Axis values.
.setPosition({ x: 5, y: 5 })
Object that fulfills interfaces: UIElementType (typeparam) and UIElement
Type of UIElement that is specified by 'builder'-parameter.
UIElementBuilder. If omitted, TextBoxBuilder will be selected. Use UIElementBuilders for selection.
Optional parameter for altering the coordinate system used for positioning the UIElement. Defaults to whole Chart in percentages [0, 100].
Permanently destroy the component.
To fully allow Garbage-Collection to free the resources used by the component, make sure to remove any references to the component and its children in application code.
let chart = ...ChartXY()
let axisX = chart.getDefaultAxisX()
// Dispose Chart, and remove all references so that they can be garbage-collected.
chart.dispose()
chart = undefined
axisX = undefined
Object itself for fluent interface
Get active cursor formatter.
Cursor formatter.
Get current cursor behavior.
SolveNearestMode or undefined
Get theme effect enabled on component or disabled.
A theme can specify an Effect to add extra visual oomph to chart applications, like Glow effects around data or other components.
Whether this effect is drawn above a particular component can be configured using the setEffect method.
// Example, disable theme effect from a particular component.
Component.setEffect(false)
For the most part, theme effects are enabled by default on most components.
Theme effect is configured with effect property.
Boolean that describes whether drawing the theme effect is enabled around the component or not.
Get font of Slice Labels.
FontSettings
Get formatter of Slice Labels.
SliceLabelFormatter - function which generates text of Labels per Slice.
Beta
Not to be confused with GlowEffect
Introduced in v7.0. API may be changed according to user feedback and reports.
Get Array of all legend boxes created using addLegendBox method.
This will not include any legend boxes that were destroyed with dispose method.
Array of legend boxes.
Abstract getGet a boolean flag which implies whether it is allowed for multiple Slices to be 'exploded' at the same time or not. When a Slice is exploded, it is drawn differently from non-exploded state
Is behavior allowed as boolean flag
Get size of control as pixels.
For stand-alone component, the size will be equal to the size of its containing HTML <div> (Control.engine.container)
For component inside Dashboard, the size will only include the component itself, so size can be less than the size of containing HTML <div>.
Object with x and y properties { x: number, y: number }, where both are pixel values.
Get theme effect enabled on component or disabled.
A theme can specify an Effect to add extra visual oomph to chart applications, like Glow effects around data or other components.
Whether this effect is drawn above a particular component can be configured using the setEffect method.
// Example, disable theme effect from a particular component.
Component.setEffect(false)
For the most part, theme effects are enabled by default on most components.
Theme effect is configured with effect property.
Boolean that describes whether drawing the theme effect is enabled around the component or not.
Get style of Pie Slices fill. This style is managed as a continuous Palette of FillStyle objects. Each Slice of Pie will be assigned an incremental index, which will be used to pick its fill style from this Palette.
So, for example... We have a Pie Chart with 5 Slices, and we give it a Palette with only 3 possible values (0 = red, 1 = green, 2 = blue). The resulting Slice fill styles will be: red, green, blue, red, green. Note that this means, that the supplied Palette will have to work in a continuous manner!
Palette
Get style of Pie Slices fill. This style is managed as a continuous Palette of FillStyle objects. Each Slice of Pie will be assigned an incremental index, which will be used to pick its fill style from this Palette.
So, for example... We have a Pie Chart with 5 Slices, and we give it a Palette with only 3 possible values (0 = red, 1 = green, 2 = blue). The resulting Slice fill styles will be: red, green, blue, red, green. Note that this means, that the supplied Palette will have to work in a continuous manner!
Palette
Get sorter of Pies' Slices as a comparator-function.
PieSliceSorter - function which sorts Slices of Pie with JavaScript API: Array.sort.
Get theme effect enabled on component or disabled.
A theme can specify an Effect to add extra visual oomph to chart applications, like Glow effects around data or other components.
Whether this effect is drawn above a particular component can be configured using the setEffect method.
// Example, disable theme effect from a particular component.
Component.setEffect(false)
For the most part, theme effects are enabled by default on most components.
Theme effect is configured with effect property.
Boolean that describes whether drawing the theme effect is enabled around the component or not.
Get font of Chart title.
FontSettings object
Beta
Not to be confused with GlowEffect
Introduced in v7.0. API may be changed according to user feedback and reports.
Remove event listener added using addEventListener.
The expected argument should be the exact same callback function that was supplied using addEventListener:
// Basic example syntax
const listener = () => {}
obj.addEventListener('click', listener)
obj.removeEventListener('click', listener)
// Basic boilerplate of custom interaction when user drags on an object
obj.addEventListener('pointerdown', (eventDown) => {
let prevCoord = eventDown
const handlePointerMove: LCJSInteractionEventListener<'pointermove'> = (eventMove) => {
const delta = { x: eventMove.clientX - prevCoord.clientX, y: eventMove.clientY - prevCoord.clientY }
prevCoord = eventMove
console.log(delta, eventMove.clientX, eventMove.clientY)
}
const handlePointerUp: LCJSInteractionEventListener<'pointerup'> = (eventUp) => {
window.removeEventListener('pointermove', handlePointerMove)
window.removeEventListener('pointerup', handlePointerUp)
}
window.addEventListener('pointermove', handlePointerMove)
window.addEventListener('pointerup', handlePointerUp)
})
Listener that was added using addEventListener.
Capture rendered state in an image file. Prompts the browser to download the created file.
NOTE: The download might be blocked by browser/plugins as harmful. To prevent this, only call the method in events tied to user-interactions. From mouse-event handlers, for example.
Has two optional parameters which directly reference JavaScript API HTMLCanvasElement.toDataURL. For supported image formats, compression quality, Etc. refer to:
https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/toDataURL
Example usage:
// Download 'screenshot.png'
Panel.saveToFile('screenshot')
// Attempt download 'maybeNotSupported.bmp'
Panel.saveToFile('maybeNotSupported', 'image/bmp')
// Attempt download jpeg.file with specified compression quality
Panel.saveToFile('fileName', 'image/jpeg', 0.50)
If 'type' is not supported by browser, an Error will be thrown.
Name of prompted download file as string. File extension shouldn't be included as it is automatically detected from 'type'-argument.
Optional type: stringA DOMString indicating the image format. The default format type is image/png.
Optional encoderOptions: numberA Number between 0 and 1 indicating the image quality to use for image formats that use lossy compression such as image/jpeg and image/webp. If this argument is anything else, the default value for image quality is used. The default value is 0.92.
Disable/Enable all animations of the Chart.
Chart itself for fluent interface.
Boolean value to enable or disable animations.
Set FillStyle of chart background.
// Example usage,
ChartXY.setBackgroundFillStyle(new SolidFill({ color: ColorRGBA( 80, 0, 0 ) }))
Related API:
Transparent chart backgrounds:
LightningChart JS charts can be configured to be fully or partially transparent.
// Example, partially transparent chart
// Engine background exists under all LCJS components. In case of Dashboard, there is only 1 shared engine background.
chart.engine.setBackgroundFillStyle(emptyFill)
// Chart background covers every 1 chart. In case of Dashboard, every chart has its own chart background.
chart.setBackgroundFillStyle(new SolidFill({ color: ColorRGBA(0, 0, 0, 100) }))
// Some charts also have a separate series background.
chart.setSeriesBackgroundFillStyle(new SolidFill({ color: ColorRGBA(0, 0, 0, 100) }))
Object itself
FillStyle or function which mutates the active FillStyle.
Set LineStyle of chart background border stroke.
// Example usage,
ChartXY.setBackgroundStrokeStyle(new SolidLine({
thickness: 2,
fillStyle: new SolidFill({ color: ColorRGBA( 0, 255, 0 ) })
}))
Related API:
Object itself
LineStyle or function which mutates the active LineStyle.
Style chart cursor using a callback function. Available style APIs can depend on the type of chart.
// Example syntax
chart.setCursor((cursor) => cursor
.setGridStrokeXStyle(new SolidLine({
thickness: 1,
fillStyle: new SolidFill({ color: ColorRGBA( 255, 0, 0 ) })
}))
)
See Cursor2D, CursorXY or Cursor3D for all available methods for configuring the cursor.
Example usage:
// Example 1, disable Y Axis tick marker & grid line.
chart.setCursor((cursor) => cursor
.setTickMarkerYVisible(false)
.setGridStrokeYStyle(emptyLine)
)
// Example 2, style cursor ResultTable.
chart.setCursor((cursor) => cursor
.setResultTable((resultTable) => resultTable
.setOrigin(UIOrigins.LeftTop)
.setTextFillStyle(new SolidFill({ color: ColorRGBA(255, 0, 0) }))
.setTextFont((font) => font
.setSize(12)
.setFamily('sans-serif')
)
.setBackground((background) => background
.setFillStyle(new SolidFill({ color: ColorRGBA(0, 0, 0, 0) }))
)
)
)
// Example 3, style cursor TickMarker X.
chart.setCursor((cursor) => cursor
.setTickMarkerX((tickMarker: UIPointableTextBox) => tickMarker
.setTextFont((font) => font.setWeight('bold'))
.setTextFillStyle(new SolidFill({ color: ColorRGBA(0, 255, 0) }))
.setBackground((background) => background.setFillStyle(emptyFill).setStrokeStyle(emptyLine)),
)
)
Object itself for fluent interface.
Set cursor formatting, controlling the text displayed in built-in cursor.
chart.setCursorFormatting((_, hit, hits) => {
return [
['Cursor pointing at'],
[hit.series], // returning a series will display the series color and its name automatically.
['X', '', hit.axisX.formatValue(hit.x)], // utilizing axis formatValue is useful for considering active zoom level and type of axis
['Y', '', hit.y.toFixed(2)], // empty string '' results in gap between cells
[{ text: 'Example', font: { weight: 'bold' }, fillStyle: fillRed }] // any cell can also be styled individually
]
})
Before overriding default cursor formatting, it is recommended to check if using setUnits or configuring Axis cursor formatting would be enough.
In order to use series specific data properties (e.g. Heatmap sample "intensity"),
you should use type guards to assert the type of the SolveResult:
// Example of using type guard in cursor formatter
Chart.setCursorFormatting((chart, hit, hits) => {
if (!isHitHeatmap(hit)) return undefined
return [hit.intensity.toFixed(1)]
})
More details in Developer documentation (Features > Cursor).
Object itself
Callback function for cursor formatting.
Set cursor behavior. This affects both built-in cursor as well as any custom cursor connected using setCustomCursor.
For possible values see SolveNearestMode.
Additionally, you can supply undefined value to disable cursor completely.
// Example, show 1 nearest solve result only
chart.setCursorMode('show-nearest')
// Example, disable cursor
chart.setCursorMode(undefined)
// Example, enable interpolation
chart.setCursorMode('show-all-interpolated')
Object itself
SolveNearestMode or undefined
Connect a custom cursor to the chart. This has 2 effects:
Custom cursors are still affected by other cursor behavior controls such as:
setCursorEnabledThe custom cursor can be anything defined by the user, such as:
// Example of plugging in a custom cursor
chart.setCustomCursor((event) => {
if (event) {
// Display custom cursor
} else {
// Hide custom cursor
}
})
Object itself
undefined to restore built-in cursor or callback function that should be triggered to display custom cursor.
Set inner radius of Pie Chart. This method can be used to style the Pie Chart as a "Donut Chart", with the center being hollow.
Pie Chart itself
Inner radius as a percentage of outer radius [0, 100]
Attach lookup table (LUT) to fill the slices with Colors based on value.
The color for the slice would be selected from a specified LUT, which contains the information about gradient steps. After setting LUT to undefined all the slices stay colorized, but no further lookup.
LUT class stores information about values and its associated colors,
const pie = lightningChart()
.Pie( { type: PieChartTypes.LabelsOnSides } )
.setLUT( new LUT (steps: [
{ value: 10, color: ColorRGBA( 0, 0, 0 ) },
{ value: 20, color: ColorRGBA( 30, 255, 0 ) },
{ value: 30, color: ColorRGBA( 60, 204, 0 ) },
{ value: 40, color: ColorRGBA( 90, 128, 0 ) },
{ value: 50, color: ColorRGBA( 255, 0, 0 ) } ) ],
interpolate: true } )
Pie itself for fluent interface
Optional lut: LUTLookup table
Set theme effect enabled on component or disabled.
A theme can specify an Effect to add extra visual oomph to chart applications, like Glow effects around data or other components.
Whether this effect is drawn above a particular component can be configured using the setEffect method.
// Example, disable theme effect from a particular component.
Component.setEffect(false)
For the most part, theme effects are enabled by default on most components.
Theme effect is configured with effect property.
Object itself.
Theme effect enabled
Set fill style of Pie Slices Labels.
Pie Chart itself
FillStyle object or function which creates a new style based on previous
Set font of Slice Labels.
Pie Chart itself
FontSettings or mutator function for existing settings
Set formatter of Slice Labels.
See SliceLabelFormatters for a collection of default options.
Pie Chart itself
SliceLabelFormatter - function which generates text of Labels per Slice.
Beta
Not to be confused with GlowEffect
Introduced in v7.0. API may be changed according to user feedback and reports.
Set if it is allowed for multiple Slices to be 'exploded' at the same time or not. When a Slice is exploded, it is drawn differently from non-exploded state
Does not affect state of already exploded Slices!
Pie Chart itself
Is behavior allowed as boolean flag
Set padding around Chart in pixels.
// Example 1, specify complete padding (four sides).
ChartXY.setPadding({ left: 16, right: 16, top: 32, bottom: 8 })
// Example 2, specify only single padding.
ChartXY.setPadding({ right: 64 })
Object itself
Number with pixel margins for all sides or datastructure with individual pixel paddings for each side. Any side can be omitted, only passed values will be overridden.
Set theme effect enabled on component or disabled.
A theme can specify an Effect to add extra visual oomph to chart applications, like Glow effects around data or other components.
Whether this effect is drawn above a particular component can be configured using the setEffect method.
// Example, disable theme effect from a particular component.
Component.setEffect(false)
For the most part, theme effects are enabled by default on most components.
Theme effect is configured with effect property.
Object itself.
Theme effect enabled
Set style of Pie Slices fill. This style is managed as a continuous Palette of FillStyle objects. Each Slice of Pie will be assigned an incremental index, which will be used to pick its fill style from this Palette.
So, for example... We have a Pie Chart with 5 Slices, and we give it a Palette with only 3 possible values (0 = red, 1 = green, 2 = blue). The resulting Slice fill styles will be: red, green, blue, red, green. Note that this means, that the supplied Palette will have to work in a continuous manner!
Pie Chart itself
Set if slices should be highlighted on mouse hover / touch. Applies to all Slices.
True if Slices should be highlighted on hover, false if not. This applies to all existing Slices and new Slices added.
Set sorter of Pies' Slices as a comparator-function.
For some commonly needed default implementations, can refer to PieSliceSorters-collection.
Pie Chart itself
PieSliceSorter - function which sorts Slices of Pie with JavaScript API: Array.sort.
Set stroke style of Pie Slices border.
Pie Chart itself
LineStyle object or function which creates a new style based on previous
Set theme effect enabled on component or disabled.
A theme can specify an Effect to add extra visual oomph to chart applications, like Glow effects around data or other components.
Whether this effect is drawn above a particular component can be configured using the setEffect method.
// Example, disable theme effect from a particular component.
Component.setEffect(false)
For the most part, theme effects are enabled by default on most components.
Theme effect is configured with effect property.
Object itself.
Theme effect enabled
Set fill style of Chart Title.
Example usage:
// Create a new style
Chart.setTitleFillStyle(new SolidFill({ color: ColorHEX('#F00') }))
// Change transparency
Chart.setTitleFillStyle((solidFill) => solidFill.setA(80))
// Set hidden
Chart.setTitleFillStyle(emptyFill)
Chart itself
Either a FillStyle object or a function, which will be used to create a new FillStyle based on current value.
Set font of Chart Title.
Example usage:
// Create a new FontSettings
Chart.setTitleFont(new FontSettings({ size: 24, style: 'italic' }))
// Change existing settings
Chart.setTitleFont((fontSettings) => fontSettings.setWeight('bold'))
Chart itself
Either a FontSettings object or a function, which will be used to create a new FontSettings based on current value.
Specifies padding after chart title.
This does not have an effect if title is hidden (empty FillStyle).
// Example 1, specify vertical margins
ChartXY.setTitleMargin({ top: 0, bottom: 10 })
// Example 2, specify margins for all sides with same value for Title.
ChartXY.setTitleMargin(40)
Chart itself for fluent interface
Gap after the chart title in pixels.
Beta
Not to be confused with GlowEffect
Introduced in v7.0. API may be changed according to user feedback and reports.
Translate a coordinate in HTML client coordinate system to relative coordinates within the component.
const locationClient = { clientX: document.body.clientWidth * 0.2, clientY: document.body.clientHeight * 0.5 }
const locationRelative = chart.translateCoordinate(locationClient, chart.coordsRelative)
// locationRelative is in pixels relative to bottom left corner of the chart
Relative coordinates can be used for positioning LightningChart JS UI components:
const textBox = chart.addUIElement(UIElementBuilders.TextBox, chart.coordsRelative)
// Left bottom of TextBox is positioned 20 pixels right and 20 pixels up from charts bottom left corner
.setOrigin(UIOrigins.LeftBottom)
.setPosition({ x: 20, y: 20 })
NOTE: Currently coordinate translations can't be guaranteed to be in sync with latest updates to charts.
For example, if you change axis interval, or add data to a series, you need to wait for 1 frame to be displayed before translateCoordinate will behave as expected.
LineSeries.add(myData)
requestAnimationFrame(() => {
// translateCoordinate should now consider data added just now.
})
Translate a coordinate from relative control coordinates to HTML client coordinate system.
// 10 pixels left and 20 pixels up from controls bottom left corner
const locationRelative = { x: 10, y: 20 }
const locationClient = chart.translateCoordinate(locationRelative, chart.coordsRelative, chart.coordsClient)
Client coordinates can be used to absolute position HTML elements using CSS, for example.
myHTMLElement.style.position = 'absolute'
myHTMLElement.style.left = locationClient.clientX
myHTMLElement.style.top = locationClient.clientY
NOTE: Currently coordinate translations can't be guaranteed to be in sync with latest updates to charts.
For example, if you change axis interval, or add data to a series, you need to wait for 1 frame to be displayed before translateCoordinate will behave as expected.
LineSeries.add(myData)
requestAnimationFrame(() => {
// translateCoordinate should now consider data added just now.
})
Abstract base class for Pie Charts. Visualizes proportions and percentages between categories, by dividing a circle into proportional segments.
Set data using PieChart.addSlice( name: string, value: number )
There are multiple implementations of PieChart, each with their own visual design and API for customizing it. List of selectable options can be found in: PieChartTypes