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BarChartProps.md

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Bar Chart Props

Example

Basic props

Prop Type Description Default value
data Array of barDataItem An item object represents a bar in the bar chart. It is described in the next table. _
width number Width of the Bar chart width of the parent
height number Height of the Bar chart (excluding the bottom label) 200
onPress Function Callback function called on press of a Bar (takes item and index as parameter) null
onLongPress Function Callback function called on long press of a Bar (takes item and index as parameter) null
onPressOut Function Callback function called on press out of a Bar (takes item and index as parameter) null
focusBarOnPress boolean used to focus a bar on press by applying styles defined in focusedBarConfig false
focusedBarConfig FocusedBarConfig styles for the focused bar including color, width, opacity, borderRadius etc _
focusedBarIndex number index of the initially focused bar, works only when focusBarOnPress is true -1
maxValue number Maximum value shown in the Y axis 200
yAxisOffset number Starting (minimum) value in the Y axis (value at the origin) 0
mostNegativeValue number The most negative value shown in the Y axis (to be used only if the data set has negative values too) _
noOfSections number Number of sections in the Y axis 10
noOfSectionsBelowXAxis number Number of sections in the Y axis below X axis (in case the data set has negative values too) 0
stepValue number Value of 1 step/section in the Y axis 20
stepHeight number Height of 1 step/section in the Y axis 20
negativeStepValue number Value of 1 step/section in the Y axis for negative values (in the 4th quadrant) stepValue
negativeStepHeight number Height of 1 step/section in the Y axis for negative values (in the 4th quadrant) stepHeight
spacing number Distance between 2 consecutive bars in the Bar chart 20
backgroundColor ColorValue Background color of the Bar chart _
sectionColors ColorValue Background color of the horizontal sections of the chart backgroundColor
customBackground CustomBackground An object used to set a custom background component (See the properties of this object below) _
scrollref any ref object that can be used to control the horizontal ScrollView inside which the chart is rendered React.useRef()
scrollToIndex number scroll to a particular index on chart load _
disableScroll boolean To disable horizontal scroll false
showScrollIndicator boolean To show horizontal scroll indicator false
indicatorColor String (iOS only) The color of the scroll indicators - ('black', 'white' or 'default') default
nestedScrollEnabled boolean Useful when the chart is used inside a horizontal ScrollView (without this, the chart's scrolling is compromised) false
showLine boolean To show a Line chart over the Bar chart with the same data false
lineData Array of items The data object for the line chart (use only when showLine is true). To hide any datapoint pass hideDataPoint prop as true in specific data item. data
lineConfig lineConfigType Properties of the Line chart shown over the Bar chart (lineConfigType) is described below defaultLineConfig
lineData2 Array of items The data object for the second line chart (use only when showLine is true) _
lineConfig2 lineConfigType Properties of the second Line chart shown over the Bar chart (lineConfigType) is described below defaultLineConfig
lineBehindBars boolean When set to true, the line chart will appear behind the Bars in case of overlap false
autoShiftLabels boolean When set to true, automatically shifts the X axis labels for negative values false
scrollToEnd boolean When set to true, the chart automatically scrolls to the rightmost bar false
scrollAnimation boolean When set to true, scroll animation is visible when the chart automatically scrolls to the rightmost bar true
scrollEventThrottle number (only for iOS) see https://reactnative.dev/docs/scrollview#scrolleventthrottle-ios 0
onScroll Function callback function called when the chart is scrolled horizontally _
onMomentumScrollEnd Function callback function called when scroll is completed _
initialSpacing number distance of the first bar from the Y axis 40
renderTooltip Function tooltip component appearing above the bar when it is pressed, takes item and index as parameters null
leftShiftForTooltip number The distance by which the tooltip component should shift towards left 0
leftShiftForLastIndexTooltip number The distance by which the tooltip component of the last bar should shift towards left 0
autoCenterTooltip boolean When set to true, automatically centers the tooltip false
adjustToWidth boolean When set to true, it auto-computes the barWidth and spacing to fit the chart in the available width / parentWidth false
parentWidth number The width of the parent View or the width that the chart should auto-fit into when adjustToWidth is true screenWidth
showValuesAsTopLabel boolean When set to true, shows the value as a label at the top of the bar false
topLabelContainerStyle object style of the top label container _
topLabelTextStyle object text style for the top labels that appear at the top of bars _

lineConfig

The lineConfig prop describes the properties of the line chart that is displayed when we set the showLine prop to true. The properties allowed by the lineConfig prop are-

type lineConfigType = {
  initialSpacing?: number;
  spacing?: number;
  curved?: boolean;
  curvature: number;
  curveType: CurveType; //CurveType is an enum defined below
  isAnimated?: boolean;
  delay?: number;
  thickness?: number;
  color?: ColorValue | String | any;
  hideDataPoints?: boolean;
  dataPointsShape?: String;
  dataPointsWidth?: number;
  dataPointsHeight?: number;
  dataPointsColor?: ColorValue | String | any;
  dataPointsRadius?: number;
  textColor?: ColorValue | String | any;
  textFontSize?: number;
  textShiftX?: number;
  textShiftY?: number;
  sfiftX?: number;
  shiftY?: number;
  startIndex?: number;
  endIndex?: number;
  showArrow?: boolean;
  arrowConfig?: arrowType;
  isSecondary?: boolean;
  focusEnabled?: boolean;
  focusedDataPointColor?: ColorValue;
  focusedDataPointRadius?: number;
  focusedDataPointIndex?: number;
};
type arrowType = {
  length?: number;
  width?: number;
  strokeWidth?: number;
  strokeColor?: string;
  fillColor?: string;
  showArrowBase?: boolean;
};

CurveType -

enum CurveType {
  CUBIC,
  QUADRATIC,
}

The default value of the lineConfig object is -

defaultLineConfig = {
  initialSpacing: initialSpacing,
  curved: false,
  curvature: 0.2,
  curveType: CurveType.CUBIC,
  isAnimated: false,
  thickness: 1,
  color: 'black',
  hideDataPoints: false,
  dataPointsShape: 'circular',
  dataPointsWidth: 4,
  dataPointsHeight: 4,
  dataPointsColor: 'black',
  dataPointsRadius: 3,
  textColor: 'gray',
  textFontSize: 10,
  textShiftX: 0,
  textShiftY: 0,
  shiftY: 0,
  delay: 0,
  startIndex: 0,
  endIndex: lineData.length - 1,
  showArrow: false,
  arrowConfig: {
    length: 10,
    width: 10,
    strokeWidth: 1,
    strokeColor: 'black',
    fillColor: 'none',
    showArrowBase: true,
  },
  isSecondary: false,
  focusEnabled: false,
  focusedDataPointColor: LineDefaults.focusedDataPointColor, // 'orange'
  focusedDataPointRadius: LineDefaults.dataPointsRadius,
};

FocusedBarConfig

type FocusedBarConfig = {
  color?: ColorValue; // default lightgreen
  sideColor?: ColorValue;
  topColor?: ColorValue;
  gradientColor?: ColorValue;
  width?: number;
  borderRadius?: number;
  roundedTop?: boolean;
  roundedBottom?: boolean;
  opacity?: number;
  barInnerComponent?: (item?: barDataItem, index?: number) => ReactNode;
};

CustomBackground

type CustomBackground = {
  color?: ColorValue
  component?: Function
  horizontalShift?: number
  verticalShift?: number
  height?: number
  width?: number
  widthAdjustment?: number
}

Alert!
These props are correlated:

  1. maxValue
  2. noOfSections
  3. stepValue

They must follow the relation:

maxValue = noOfSections * stepValue;

So, all the three must be used together. Using any 1 or 2 of them may produce absurd results


Combine Line Chart using showLine

You can add a line chart to your <BarChart/> component by passing the showLine prop. The properties of this line chart can be controlled using the lineConfig prop which is an object. The lineConfig object is described below-

Property Type Description Default value
initialSpacing number distance of the first data point from the Y axis initialSpacing for the Bar Chart
curved boolean To show curved line joining the data points false
isAnimated boolean To show animates Line Chart false
delay number Delay (in milliseconds) before starting the animation of the line 0
thickness number Thickness of the Line 1
color ColorValue Color of the Line 'black'
hideDataPoints boolean To hide data points along the Line chart false
dataPointsShape String Shape of the data points ('rectangular' or 'circular') 'circular'
dataPointsWidth number Width of data points (when data points' shape is rectangular) 4
dataPointsHeight number Height of data points (when data points' shape is rectangular) 4
dataPointsColor ColorValue Color of the data points 'black'
dataPointsRadius number Radius of data points (when data points' shape is circular) 3
textColor ColorValue Color of the dataPointText 'gray'
textFontSize number Font size of the dataPointText 10
textShiftX number To shift the dataPointText text horizontally 0
textShiftY number To shift the dataPointText text vertically 0
shiftY number To shift the Line chart up or down by the given quantity m 0
startIndex number Start index for data line (used to display data lines having breaks) 0
endIndex number End index for data line (used to display data lines having breaks) lineData.length -1

Item description (barDataItem)

Key Value type Description
value number Value of the item representing height of the bar
barWidth number Width of the bar
onPress function Function called on pressing the bar
onLongPress function Function called on long pressing the bar
onPressOut Function Callback function called on press out of a bar
disablePress boolean Prop to disable the press action, defaults to false
frontColor ColorValue Color of the bar
sideColor ColorValue Color of the side view of the bar, only for 3 D
sideWidth number Width of the side view of the bar, only for 3 D
topColor ColorValue Color of the top view of the bar, only for 3 D
barStyle object style object for the Bars
showGradient boolean Prop to enable linear gradient for the bar color, defaults to false
gradientColor ColorValue Along with frontColor, this prop constitutes the 2 colors for gradient
label string Label text appearing below the bar (under the X axis)
labelWidth number Width of the Label text appearing below the bar (under the X axis)
labelTextStyle object Style object for the label text appearing below the bar
labelComponent Component Custom label component appearing below the bar
secondaryLabel string Label text appearing above the secondary X-axis (at the top of the chart)
secondaryLabelComponent Component Custom label component appearing above the secondary X-axis (at the top of the chart)
secondaryLabelTextStyle object Style object for the label text of secondary X-axis (at the top of the chart)
labelsDistanceFromXaxis number Distance of the X Axis label from the X axis
topLabelComponent Component Custom component appearing above the bar
topLabelContainerStyle object Style object for the container of the custom component appearing above the bar
cappedBars boolean To show caps on the top of bar
capThickness number Thickness of the bar cap
capColor ColorValue Color of the bar cap
capRadius number Border radius of the bar cap
barBorderWidth number Border width of the bar
barBorderColor ColorValue Border color of the bar
barBorderRadius number Border radius of the bar
barBorderTopLeftRadius number Top left border radius of the bar
barBorderTopRightRadius number Top right border radius of the bar
barBorderBottomLeftRadius number Bottom left border radius of the bar
barBorderBottomRightRadius number Bottom right border radius of the bar
barMarginBottom number margin at the bottom of the bar (above X axis)
spacing number Distance of the next Bar from the currennt Bar
barBackgroundPattern Component A svg component containing the background pattern for bars
patternId String ID of the pattern component
leftShiftForTooltip number The distance by which the tooltip component should shift towards left
showXAxisIndex boolean show small graduation at the X axis for the corresponding bar

Axes and rules related props

Prop Type Description Default value
xAxisLength number X axis length width of the chart
xAxisColor ColorValue X axis color black
xAxisThickness number X axis thickness 1
yAxisColor ColorValue Y axis color black
yAxisThickness number Y axis thickness 1
yAxisExtraHeight number Extra length of Y axis at the top (height / 20)
xAxisType RuleType solid or dotted/dashed solid
yAxisLabelWidth number Width of the Y axis Label container 35
yAxisTextStyle object Style object for the Y axis text style _
yAxisTextNumberOfLines number Number of lines for y axis label text 1
yAxisLabelContainerStyle object Style object for the Y axis label container _
trimYAxisAtTop boolean Removes the extra length of the Y axis from the top false
horizontalRulesStyle object Style object for the horizontal rules container _
showFractionalValues boolean Allow fractional values for the Y axis label false
roundToDigits number Rounds the y axis values to given number of digits after decimal point 1
yAxisLabelPrefix String The String prepended to the y axis label text (for example- '$') ''
yAxisLabelSuffix String The String appended to the y axis label text ''
hideYAxisText boolean To hide Y axis label text false
formatYLabel (label: string) => string a callback function that takes the label generated by the library and modifies it. _
yAxisSide String Tells which side of the chart, should the y axis be present, defaults to 'left' 'left'
rulesLength number Length of the horizontal rules width of the chart
rulesColor ColorValue Color of the horizontal rules lightgray
rulesThickness number Thickness of the horizontal rules 1
hideRules boolean To hide the horizontal rules false
rulesType RuleType solid or dotted/dashed solid
dashWidth number width of each dash 4
dashGap number gap between 2 dashes 8
rulesConfigArray Array Array of rulesConfig objects, used to customise the properties (like color, type etc) of specific rules _
showReferenceLine1 boolean show reference line false
referenceLine1Config referenceConfigType properties of reference line like thickness, color etc (described below the table) _
referenceLine1Position number position of reference line containerHeight / 2
showReferenceLine2 boolean show second reference line false
referenceLine2Config referenceConfigType properties of reference line like thickness, color etc (described below the table) _
referenceLine2Position number position of second reference line 3*containerHeight / 2
showReferenceLine3 boolean show third reference line false
referenceLine3Config referenceConfigType properties of reference line like thickness, color etc (described below the table) _
referenceLine3Position number position of third reference line containerHeight / 3
referenceLinesOverChartContent boolean used to render the reference lines over the rest of the chart content. true
showVerticalLines boolean To show vertical lines false
verticalLinesColor ColorValue Color of the vertical lines lightgray
verticallinesThickness number Thickness of the vertical lines 1
verticalLinesHeight number Height of the vertical lines chart height
verticalLinesStrokeDashArray Array Array of 2 numbers denoting the dashWidth and dashGap of the lines. Used to render dashed/dotted vertical line ''
verticalLinesShift number vertical lines are aligned with bars. Shift them left or right using +ve or -ve value of verticalLinesShift 0
verticalLinesZIndex number Z index of the vertical lines -1
noOfVerticalLines number Number of vertical lines displayed data.length
verticalLinesSpacing number Distance between consecutive vertical lines spacing
verticalLinesStrokeLinecap 'butt' | 'round' | 'square' Linecap of the vertical lines (see stroke-linecap in svg) 'butt'
showXAxisIndices boolean To show the pointers on the X axis false
xAxisIndicesHeight number Height of the pointers on the X axis 2
xAxisIndicesWidth number Width of the pointers on the X axis 4
xAxisIndicesColor ColorValue Color of the pointers on the X axis black
showYAxisIndices boolean To show the pointers on the Y axis false
yAxisIndicesHeight number Height of the pointers on the Y axis 2
yAxisIndicesWidth number Width of the pointers on the Y axis 4
yAxisIndicesColor ColorValue Color of the pointers on the X axis black
yAxisLabelTexts Array Array of label texts to be displayed along y axis null
xAxisLabelTexts Array Array of label texts to be displayed below x axis null
xAxisLabelTextStyle object Style of label texts to be displayed below x axis null
rotateLabel boolean To rotate the X axis labels (by 60deg) false
hideAxesAndRules boolean To hide axes, rules, labels altogether false
hideOrigin boolean To hide the y Axis label at origin (i.e. 0) false
labelWidth number Width of the Label text appearing below the bar (under the X axis) barWidth
labelsDistanceFromXaxis number Distance of the X Axis label from the X axis 0
xAxisTextNumberOfLines number Number of lines for x axis label text 1
xAxisLabelsHeight number Height of X axis labels container xAxisTextNumberOfLines * 18
xAxisLabelsVerticalShift number prop to adjust the vertical position of X axis labels (move X axis labels up or down) 0
labelsExtraHeight number used to display large rotated labels on X-axis (useful when using the rotateLabel prop) 0
secondaryYAxis secondaryYAxisType displays and controls the properties of the secondary Y axis on the right side null
secondaryData Array of items the secondary data that will be rendered along the secondary Y axis undefined
secondaryXAxis XAxisConfig properties of the secondary X-axis (appearing at the top of the chart) values of the primary X-axis

Note If you are setting yAxisSide to 'right', make sure to specify the width of the chart, using the width prop.

type RuleType = 'solid' | 'dashed' | 'dotted';
type RulesConfig = {
  rulesLength?: number;
  rulesColor?: ColorValue;
  rulesThickness?: number;
  rulesType?: RuleType;
  dashWidth?: number;
  dashGap?: number;
};

ReferenceConfigType has following properties-

type referenceConfigType = {
  thickness: number;
  width: number;
  color: ColorValue | String | any;
  type: ruleTypes;
  dashWidth: number;
  dashGap: number;
  labelText: String;
  labelTextStyle: object;
  zIndex: number;
  stripBehindBars: boolean;
};

XAxisConfig has following properties-

type XAxisConfig {
  thickness?: number
  color?: ColorValue
  labelsDistanceFromXaxis?: number
  labelsHeight?: number
  labelsTextStyle?: any
  labelTexts?: string[]
}

secondaryYAxis

Use this prop to render a secondary Y axis on the right side of the chart. secondaryYAxis is an object of type of secondaryYAxisType You can control the properties of secodary Y axis by passing an object of properties. Following is the type definition of the secondaryYAxisType object

type secondaryYAxisType = {
  noOfSections?: number,
  maxValue?: number,
  mostNegativeValue?: nuepValue?: number,
  stepHeight?: number,
  showFractionalValues?: boolean,
  roundToDigits?: number,

  showYAxisIndices?: boolean,
  yAxisIndicesHeight?: number,
  yAxisIndicesWidth?: number,
  yAxisIndicesColor?: ColorValue,

  yAxisSide?: yAxisSides,
  yAxisOffset?: number,
  yAxisThickness?: number,
  yAxisColor?: ColorValue,
  yAxisLabelContainerStyle?: any,
  yAxisLabelTexts: Array<string> | undefined,
  yAxisTextStyle?: any,
  yAxisTextNumberOfLines?: number,
  yAxisLabelWidth?: number,
  hideYAxisText?: boolean,
  yAxisLabelPrefix?: string,
  yAxisLabelSuffix?: string,
  hideOrigin?: boolean,
  formatYLabel?: (label: string) => string;
};

All the properties are optional. If you don't set a property in the secondaryYAxis, it takes the default values from the primary Y axis.

Bar related props

Prop Type Description Default value
barWidth number Width of the bar 30
barStyle object style object for the Bars _
isThreeD boolean Prop to render 3 dimensional bars false
frontColor ColorValue Color of the bar 'black' for 2D, '#C0CA3A' for 3D
sideColor ColorValue Color of the side view of the bar, only for 3 D '#887A24'
topColor ColorValue Color of the top view of the bar, only for 3 D '#D9E676'
sideWidth number Width of the side view of the bar, only for 3 D barWidth / 2
showGradient boolean Prop to enable linear gradient for the bar color false
gradientColor ColorValue Along with frontColor, gradientColor constitutes the 2 colors for gradient white
roundedTop boolean To show rounded top white
roundedBottom boolean To show rounded bottom white
activeOpacity number activeOpacity on pressing the bar 0.2
disablePress boolean Prop to disable the bar press action false
barBorderWidth number Border width of the bar 0
barBorderColor ColorValue Border color of the bar 'gray'
barBorderRadius number Border radius of the bar 0
barBorderTopLeftRadius number Top left border radius of the bar barBorderRadius | 0
barBorderTopRightRadius number Top right border radius of the bar barBorderRadius | 0
barBorderBottomLeftRadius number Bottom left border radius of the bar barBorderRadius | 0
barBorderBottomRightRadius number Bottom right border radius of the bar barBorderRadius | 0
barMarginBottom number margin at the bottom of the bar (above X axis) 0
barBackgroundPattern Component A svg component containing the background pattern for bars _
patternId String ID of the pattern component _
minHeight number Minimum height of the Bars 0

Animation related props

Prop Type Description Default value
isAnimated boolean To show animates BarChart. Animation occurs onLoad and on value change false
animationDuration number Duration of the animations 800
animationEasing Easing Easing applied to the animation Easing.ease

Alert!
While rendering an Animated Bar chart, y axis labels may not appear sometimes. This can be fixed using a key prop as shown -

<BarChart key={'xyz'} data={data} isAnimated />

Pagination related props

Prop Type Description Default value
onEndReached Function Callback function called when the chart is scrolled upto end _
onStartReached Function Callback function called when the chart is scrolled upto start _
endReachedOffset number distance before end of scroll when onEndReached should be triggered 80

Bar related props for making Capped Bar chart

Prop Type Description Default value
cappedBars boolean To show caps on the top of bars false
capThickness number Thickness of the bar caps 6
capColor ColorValue Color of the bar caps gray
capRadius number Border radius of the bar caps 0

pointerConfig

pointerConfig is an object, when passed as a prop, creates a magical effect. It lets the user scroll over chart to move the pointer along the chart. To know more about pointerConfig, see pointerConfig in the Line chart props page


Props for horizontal BarChart

Prop Type Description Default value
horizontal boolean Render horizontal BarChart false
rtl boolean Render the chart from right to left false
shiftX number Shift the chart towards left or right by given value (only in horizontal charts) 0
shiftY number Shift the chart upwards or downwards by given value (only in horizontal charts) 0
rotateYAxisTexts number angle by which the Y axis label texts should rotate in horizontal charts -90
yAxisAtTop boolean In horizontal BarCharts the Y axis appears at bottom by default. Set it to true for otherwise false
intactTopLabel boolean To rotate the top label component to make it intact with the Bars false

Props for Stacked Bar Charts

To render stacked charts, you need to pass the prop stackData instead of data.

The structure of stackData is-

[
    {
      stacks:
        [
            {
                value: 10, color: 'red', onPres: someFunction
            },
            {
                value: 20, color: 'blue', marginBottom: 1, onPres: someFunction
            },
            ...
        ],
      label: 'Jan',
      ...otherProps,
    },
    {
      stacks:
        [
            {
                value: 8, color: 'red', onPres: someFunction
            },
            {
                value: 17, color: 'blue', marginBottom: 1, onPres: someFunction
            },
            ...
        ],
      label: 'Feb',
      ...otherProps,
    },
    ...
]

The stackData passed to the BarChart component is an array of objects.
Each object contains a mandatory key named stacks.
The value corresponding to the stacks key is an array of objects, each object representing a section of the stack.

Prop Type Description Default value
stackData Array of stack arrays A stack array represents a stack of bars in the bar chart. It is described in the next table false
barBorderRadius number Border radius of each bar of the stack 0
barBorderTopLeftRadius number Top left border radius of each bar of the stack barBorderRadius | 0
barBorderTopRightRadius number Top right border radius of each bar of the stack barBorderRadius | 0
barBorderBottomLeftRadius number Bottom left border radius of each bar of the stack barBorderRadius | 0
barBorderBottomRightRadius number Bottom right border radius of each bar of the stack barBorderRadius | 0
stackBorderRadius number Border radius of the top and bottom bars of the stack
stackBorderTopLeftRadius number Top left border radius of the top bar of the stack
stackBorderTopRightRadius number Top right border radius of the top bar of the stack
stackBorderBottomLeftRadius number Bottom left border radius of the bottom bar of the stack
stackBorderBottomRightRadius number Bottom right border radius of the bottom bar of the stack
autoShiftLabelsForNegativeStacks boolean Whether the x axis labels should auto shift to a position below the bar, if the bar is under x-axis due to negative value

Note The frontColor prop is replaced by color prop in Stacked Bar charts.

Stack Array description

Key Value type Description
stacks array Array of stack items A stack is made of 1 or more objects of the type described in the next table
label string Label text appearing below the stack (under the X axis)
labelTextStyle Style object for the label text appearing below the stack
barWidth number
spacing number
borderRadius number
borderTopLeftRadius number
borderTopRightRadius number
borderBottomLeftRadius number
borderBottomRightRadius number

A single stack item can be depicted as-

alt text

Stack item description

Key Value type Description
value number Value of the item representing height of the stack item
color ColorValue Color of the stack item
onPress function Function called on pressing the stack item
onLongPress function Function called on long pressing the stack item
onPressOut Function Callback function called on press out of a bar
marginBottom number margin below a particular stack section
barBorderRadius number Border radius of a stack section
borderTopLeftRadius number borderTopLeftRadius for a stack section
borderTopRightRadius number borderTopRightRadius for a stack section
borderBottomLeftRadius number borderBottomLeftRadius for a stack section
borderBottomRightRadius number borderBottomRightRadius for a stack section
showGradient boolean Prop to enable linear gradient for the bar color, defaults to false
gradientColor ColorValue Along with frontColor, this prop constitutes the 2 colors for gradient
barWidth number Width of the bar
showXAxisIndex boolean show small graduation at the X axis for the corresponding stack