Thermometer chart

Example

<script>
    new RGraph.Thermometer({
        id: 'cvs',
        min: 0,
        max: 100,
        value: 52,
        options: {
            marginLeft: 45,
            marginRight: 45,
            tooltips: '<span style="font-size: 14pt">Todays temperature</span><br/>%{key}',
            colors: ['red'],
            tooltipsFormattedKeyLabels: ['London'],
            tooltipsFormattedUnitsPost: '°',
            tooltipsCss: {
                fontSize: '18pt',
                textAlign: 'left'
            }
        }
    }).draw();
</script>
View example on CodePen

Properties

You can use these properties to control how the chart appears. You can set them by including them in the options section of the configuration as shown above.

Margin properties

PropertyDescriptionDefault
marginLeftThe left margin of the chart, (the margin is where the labels and title are)).35
marginRightThe right margin of the chart, (the margin is where the labels and title are).35
marginTopThe top margin of the chart, (the margin is where the labels and title are).35
marginBottomThe bottom margin of the chart, (the margin is where the labels and title are).35
marginLeft
The left margin of the chart, (the margin is where the labels and title are)).
Default: 35

marginRight
The right margin of the chart, (the margin is where the labels and title are).
Default: 35

marginTop
The top margin of the chart, (the margin is where the labels and title are).
Default: 35

marginBottom
The bottom margin of the chart, (the margin is where the labels and title are).
Default: 35

Background properties

PropertyDescriptionDefault
backgroundColorThe default background color.white
backgroundColor
The default background color.
Default: white

Color properties

PropertyDescriptionDefault
colorsAn array of the colors of the bars.['Gradient(#c00:red:#f66:#fcc)']
colorsStrokeThe color of the border around the Thermometer.black
colors
An array of the colors of the bars.
Default: ['Gradient(#c00:red:#f66:#fcc)']

colorsStroke
The color of the border around the Thermometer.
Default: black

Title properties

PropertyDescriptionDefault
titleThe title of the chart, if any.null
titleFontThe font that the title is rendered in. If not specified the textFont setting is used (usually Arial).null
titleSizeThe size of the title. If not specified the size is usually 4pt bigger than the textSize setting.null
titleBoldWhether the title is bold or not.null
titleItalicWhether the title is italic or not.null
titleColorThe color of the title.null
titleXTo give the exact X coordinate for the title - use this. This can also be a string like this: "-5" - in which case it's converted to a number and added to the calculated coordinate - allowing you to adjust the calculated coordinate.null
titleYTo give the exact Y coordinate for the title - use this. This can also be a string like this: "-5" - in which case it's converted to a number and added to the calculated coordinate - allowing you to adjust the calculated coordinate.null
titleHalignThe horizontal alignment of the title.center (can change depending on other options)
titleValignThe vertical alignment of the title.center (can change depending on other options)
titleOffsetxYou can use this property to adjust the positioning of the title in the horizontal direction (positive values adjust the title to the right and negative values adjust it to the left). 0
titleOffsetyYou can use this property to adjust the positioning of the title in the vertical direction (positive values adjust the title downwards and negative values adjust it upwards). 0
titleSubtitleThe subtitle of the chart. If a subtitle is specified the title is moved up to accommodate it. As such you might need to give a larger marginTop value.null
titleSubtitleSizeThe size of the font used to render the subtitle.null
titleSubtitleColorThe color of the subtitle.#aaa
titleSubtitleFontThe font used to render the subtitle.null
titleSubtitleBoldWhether the subtitle is bold or not.null
titleSubtitleItalicWhether the subtitle is italic or not.null
titleSubtitleOffsetxUse this property to adjust the horizontal position of the subtitle. 0
titleSubtitleOffsetyUse this property to adjust the vertical position of the subtitle. 0
titleSideThis is the text that is used as the title on the left-hand-side of the Thermometer.An empty string
titleSideFontThe font that the title is rendered in.null
titleSideSizeThe size of the title.null
titleSideColorThe color of the title.null
titleSideBoldWhether the title is bold or not.null
titleSideItalicWhether the title is italic or not.null
titleSideOffsetxYou can use this property to adjust the positioning of the title in the horizontal direction (positive values adjust the title to the right and negative values adjust it to the left). 0
titleSideOffsetyYou can use this property to adjust the positioning of the title in the vertical direction (positive values adjust the title downwards and negative values adjust it upwards). 0
title
The title of the chart, if any.
Default: null

titleFont
The font that the title is rendered in. If not specified the textFont setting is used (usually Arial).
Default: null

titleSize
The size of the title. If not specified the size is usually 4pt bigger than the textSize setting.
Default: null

titleBold
Whether the title is bold or not.
Default: null

titleItalic
Whether the title is italic or not.
Default: null

titleColor
The color of the title.
Default: null

titleX
To give the exact X coordinate for the title - use this. This can also be a string like this: "-5" - in which case it's converted to a number and added to the calculated coordinate - allowing you to adjust the calculated coordinate.
Default: null

titleY
To give the exact Y coordinate for the title - use this. This can also be a string like this: "-5" - in which case it's converted to a number and added to the calculated coordinate - allowing you to adjust the calculated coordinate.
Default: null

titleHalign
The horizontal alignment of the title.
Default: center (can change depending on other options)

titleValign
The vertical alignment of the title.
Default: center (can change depending on other options)

titleOffsetx
You can use this property to adjust the positioning of the title in the horizontal direction (positive values adjust the title to the right and negative values adjust it to the left).
Default: 0

titleOffsety
You can use this property to adjust the positioning of the title in the vertical direction (positive values adjust the title downwards and negative values adjust it upwards).
Default: 0

titleSubtitle
The subtitle of the chart. If a subtitle is specified the title is moved up to accommodate it. As such you might need to give a larger marginTop value.
Default: null

titleSubtitleSize
The size of the font used to render the subtitle.
Default: null

titleSubtitleColor
The color of the subtitle.
Default: #aaa

titleSubtitleFont
The font used to render the subtitle.
Default: null

titleSubtitleBold
Whether the subtitle is bold or not.
Default: null

titleSubtitleItalic
Whether the subtitle is italic or not.
Default: null

titleSubtitleOffsetx
Use this property to adjust the horizontal position of the subtitle.
Default: 0

titleSubtitleOffsety
Use this property to adjust the vertical position of the subtitle.
Default: 0

titleSide
This is the text that is used as the title on the left-hand-side of the Thermometer.
Default: An empty string

titleSideFont
The font that the title is rendered in.
Default: null

titleSideSize
The size of the title.
Default: null

titleSideColor
The color of the title.
Default: null

titleSideBold
Whether the title is bold or not.
Default: null

titleSideItalic
Whether the title is italic or not.
Default: null

titleSideOffsetx
You can use this property to adjust the positioning of the title in the horizontal direction (positive values adjust the title to the right and negative values adjust it to the left).
Default: 0

titleSideOffsety
You can use this property to adjust the positioning of the title in the vertical direction (positive values adjust the title downwards and negative values adjust it upwards).
Default: 0

Labels and text properties

PropertyDescriptionDefault
textAccessibleA new feature in 2016 that allows you to use DOM text in place of canvas text. It makes for much higher quality text that you can also select if desired (for copy/paste operations). It won't fit all situations and you can read more about the DOM text feature here. A good way to control borders/margins/padding etc is not to set them on the canvas but to wrap the canvas in a div and set them on that like this:
<div style="margin-left: 50px; display: inline-block">
    <canvas id="cvs" width="650" height="250"></canvas>
</div>
false
textAccessibleOverflowThis can be visible or hidden and it controls whether the text is clipped to the edges of the canvas. It defaults to be visible and means you can set small margins if you wish.visible
textAccessiblePointereventsThis controls whether the DOM text responds to mouse-based events or not (it sets the pointer-events CSS property to none).true
textBoldWhether text on the Thermometer chart is bold or not.false
textItalicWhether text on the Thermometer chart is italic or not.false
textFontThe font used to render text on the Thermometer chart.Arial, Verdana, sans-serif
textSizeThe size of text on the Thermometer chart.12
textColorThe color of text on the Thermometer chart.black
labelsValueThis controls whether the Thermometers value is shown as a label.true
labelsValueDecimalsThis controls how many decimals are shown if the value is being shown. It falls back to use scaleDecimals if this is not specified. 0
labelsValuePointThe decimal point character. It falls back to use scalePoint if this is not specified.null
labelsValueThousandThe character that's used as the thousand separator. It falls back to use scaleThousand if this is not specified.null
labelsValueUnitsPreUnits that are prepended to the value. It falls back to use scaleUnitsPre if this is not specified.null
labelsValueUnitsPostUnits that are appended to the value. It falls back to use scaleUnitsPost if this is not specified.null
labelsValueFontThe font used to render the label. This defaults to the textFont setting.null
labelsValueSizeThe size of the value label. This defaults to the textSize setting.null
labelsValueColorThe color of the value label. This defaults to the textColor setting.null
labelsValueBoldWhether the labelsValue label is bold or not. This falls back to the textBold setting.null
labelsValueItalicWhether the labelsValue label is italic or not. This falls back to the textItalic setting.null
labelsValueOffsetxThis allows you finer-grained control in the horizontal direction over the text positioning if you need it. 0
labelsValueOffsetyThis allows you finer-grained control in the vertical direction over the text positioning if you need it. 0
labelsCountA value that controls how many scale labels there are. Keep in mind that if you use this it may result in decimals, and to see the full number you may need to use the scaleDecimals property.5
labelsFontThe font used by the vertical labels.null
labelsSizeThe size of the vertical labels.null
labelsColorThe color of the vertical labels.null
labelsBoldWhether the vertical labels are bold or not.null
labelsItalicWhether the vertical labels are italic or not.null
labelsDecimalsHow many decimals are displayed.null
labelsUnitsPreUnits that are prepended to the label.null
labelsUnitsPostUnits that are appended to the label.null
labelsPointThe point character used by the labels.null
labelsThousandThe thousand character used by the labels.null
labelsOffsetxThis allows you finer-grained control in the horizontal direction over the text positioning if you need it. 0
labelsOffsetyThis allows you finer-grained control in the vertical direction over the text positioning if you need it. 0
textThis allows you to add custom text to your chart if you want to. There's a dedicated page that describes this option here.null
textAccessible
A new feature in 2016 that allows you to use DOM text in place of canvas text. It makes for much higher quality text that you can also select if desired (for copy/paste operations). It won't fit all situations and you can read more about the DOM text feature here. A good way to control borders/margins/padding etc is not to set them on the canvas but to wrap the canvas in a div and set them on that like this:
<div style="margin-left: 50px; display: inline-block">
    <canvas id="cvs" width="650" height="250"></canvas>
</div>

Default: false

textAccessibleOverflow
This can be visible or hidden and it controls whether the text is clipped to the edges of the canvas. It defaults to be visible and means you can set small margins if you wish.
Default: visible

textAccessiblePointerevents
This controls whether the DOM text responds to mouse-based events or not (it sets the pointer-events CSS property to none).
Default: true

textBold
Whether text on the Thermometer chart is bold or not.
Default: false

textItalic
Whether text on the Thermometer chart is italic or not.
Default: false

textFont
The font used to render text on the Thermometer chart.
Default: Arial, Verdana, sans-serif

textSize
The size of text on the Thermometer chart.
Default: 12

textColor
The color of text on the Thermometer chart.
Default: black

labelsValue
This controls whether the Thermometers value is shown as a label.
Default: true

labelsValueDecimals
This controls how many decimals are shown if the value is being shown. It falls back to use scaleDecimals if this is not specified.
Default: 0

labelsValuePoint
The decimal point character. It falls back to use scalePoint if this is not specified.
Default: null

labelsValueThousand
The character that's used as the thousand separator. It falls back to use scaleThousand if this is not specified.
Default: null

labelsValueUnitsPre
Units that are prepended to the value. It falls back to use scaleUnitsPre if this is not specified.
Default: null

labelsValueUnitsPost
Units that are appended to the value. It falls back to use scaleUnitsPost if this is not specified.
Default: null

labelsValueFont
The font used to render the label. This defaults to the textFont setting.
Default: null

labelsValueSize
The size of the value label. This defaults to the textSize setting.
Default: null

labelsValueColor
The color of the value label. This defaults to the textColor setting.
Default: null

labelsValueBold
Whether the labelsValue label is bold or not. This falls back to the textBold setting.
Default: null

labelsValueItalic
Whether the labelsValue label is italic or not. This falls back to the textItalic setting.
Default: null

labelsValueOffsetx
This allows you finer-grained control in the horizontal direction over the text positioning if you need it.
Default: 0

labelsValueOffsety
This allows you finer-grained control in the vertical direction over the text positioning if you need it.
Default: 0

labelsCount
A value that controls how many scale labels there are. Keep in mind that if you use this it may result in decimals, and to see the full number you may need to use the scaleDecimals property.
Default: 5

labelsFont
The font used by the vertical labels.
Default: null

labelsSize
The size of the vertical labels.
Default: null

labelsColor
The color of the vertical labels.
Default: null

labelsBold
Whether the vertical labels are bold or not.
Default: null

labelsItalic
Whether the vertical labels are italic or not.
Default: null

labelsDecimals
How many decimals are displayed.
Default: null

labelsUnitsPre
Units that are prepended to the label.
Default: null

labelsUnitsPost
Units that are appended to the label.
Default: null

labelsPoint
The point character used by the labels.
Default: null

labelsThousand
The thousand character used by the labels.
Default: null

labelsOffsetx
This allows you finer-grained control in the horizontal direction over the text positioning if you need it.
Default: 0

labelsOffsety
This allows you finer-grained control in the vertical direction over the text positioning if you need it.
Default: 0

text
This allows you to add custom text to your chart if you want to. There's a dedicated page that describes this option here.
Default: null

Shadow properties

PropertyDescriptionDefault
shadowWhether a drop shadow is applied.true
shadowColorThe color of the shadow.gray
shadowOffsetxThe horizontal offset of the shadow. 0
shadowOffsetyThe vertical offset of the shadow. 0
shadowBlurThe severity of the shadow blurring effect.15
shadow
Whether a drop shadow is applied.
Default: true

shadowColor
The color of the shadow.
Default: gray

shadowOffsetx
The horizontal offset of the shadow.
Default: 0

shadowOffsety
The vertical offset of the shadow.
Default: 0

shadowBlur
The severity of the shadow blurring effect.
Default: 15

Scale properties

PropertyDescriptionDefault
scaleVisibleDefaulting to false, this controls whether the scale is visible.false
scaleDecimalsThis allows you to control the number of decimals that the labels have. 0
scalePointThe character that's used as the decimal point..
scaleThousandThe character that's used as the thousand separator.,
scaleUnitsPreThe units that the Y-axis is measured in. This string is displayed before the number, allowing you to specify values such as $50.none
scaleUnitsPostThe units that the Y-axis is measured in. This string is displayed after the number, allowing you to specify values such as 50ms.none
scaleVisible
Defaulting to false, this controls whether the scale is visible.
Default: false

scaleDecimals
This allows you to control the number of decimals that the labels have.
Default: 0

scalePoint
The character that's used as the decimal point.
Default: .

scaleThousand
The character that's used as the thousand separator.
Default: ,

scaleUnitsPre
The units that the Y-axis is measured in. This string is displayed before the number, allowing you to specify values such as $50.
Default: none

scaleUnitsPost
The units that the Y-axis is measured in. This string is displayed after the number, allowing you to specify values such as 50ms.
Default: none

Interactive features properties

PropertyDescriptionDefault
adjustableDefaulting to false, this determines whether your bar chart will be adjustable.false
tooltipsA numerically indexed array of tooltips that are shown when a bar is clicked. These can contain HTML.null
tooltipsHighlightSet this to false if you don't want your charts to be highlighted.true
tooltipsEffectThe effect used for showing tooltips. Possible values are slide fade or none.slide
tooltipsEventThis is the event that triggers the tooltips. It can be either click or mousemove.onclick
tooltipsOverrideIf you wish to handle showing tooltips yourself, this should be a function object which does just that. There's more information on the tooltips documentation page.null
tooltipsFormattedPointWhen using formatted tooltip strings this is used as the point when using the %{value_formatted} option..
tooltipsFormattedThousandWhen using formatted tooltip strings this is used as the thousand separator when using the %{value_formatted} option.,
tooltipsFormattedDecimalsWhen using formatted tooltip strings this specifies the number of decimals when using the %{value_formatted} option. 0
tooltipsFormattedUnitsPreWhen using formatted tooltip strings these units are prepended to the number when using the %{value_formatted} option.(an empty string)
tooltipsFormattedUnitsPostWhen using formatted tooltip strings these units are appended to the number when using the %{value_formatted} option.(an empty string)
tooltipsFormattedKeyColorsWhen using formatted tooltip strings you can give specific colors for the %{key} option to use.null
tooltipsFormattedKeyColorsShapeThis is the shape that's used in the tooltip key. It can be square or circlesquare
tooltipsFormattedKeyColorsCss By using this property you can add CSS values to the key color shape that appears in the tooltip key. Note the property name is "color" and not "colors" like previous properties. It should be an object of CSS properties like this:
tooltipsFormattedKeyColorsCss : {
    border: "1px solid #ddd";
}
null
tooltipsFormattedKeyLabelsWhen using formatted tooltip strings these are the labels that are displayed.[] (an empty array)
tooltipsFormattedListTypeWith this property you can switch between an unordered list (the default) and an ordered list. Possible values are ul and ol.ul
tooltipsFormattedListItemsThis should be a two-dimension array of the list items that are to be shown for all of the tooltips. An example of this property is:
tooltipsFormattedListItems: [
    ['Bill','Jerry','Berty'], // First tooltip
    ['Gill','Carrie','Lucy'], // Second tooltip
    ['Pob','Nobby','Hilda']   // Third tooltip
]
You can use CSS to style this list - for example:
.RGraph_tooltip ul#rgraph_formatted_tooltips_list li {
    text-align: left;
    color: yellow;
}
null
tooltipsFormattedTableHeadersWhen showing a table in the tooltips this can be an array of headers for the table. These are added to the tooltip using th tags.null
tooltipsFormattedTableDataThis is the data that is added to the table. This is a 3-dimensional array so it's easy to make a mistake. See the example, copy the code from it and then modify it suit. You'll create fewer bugs this way.null)
tooltipsPointerBy default the tooltips have a small triangular pointer that points to the shape that was clicked on. You can turn this off with this property.true
tooltipsPointerCssIf you want any CSS values applied to the tooltips pointer (a CSS border, for example) then specify an object containing those values to this property. For example:
tooltipsPointerCss: {
    borderLeft: 'gray 2px solid',
    borderBottom: 'gray 2px solid'
}
null
tooltipsPositionStaticThe new default (as of August 2020) is for tooltips to be positioned statically and not be dependent on the mouse position. If you don't want this for whatever reason, you can disable it with this setting. When you set it to false tooltips are positioned next to the mouse pointer.true
tooltipsCssClassThis is the name of the CSS class the chart uses.RGraph_tooltip
tooltipsCssIf you want to specify some CSS that gets applied to all of the tooltips, but don't want to use the RGraph.tooltips.style object (which gets applied to all of the tooltips on the page for every chart) you can use this property to give some per-object CSS for the tooltips. These are CSS styles that get applied to all of the tooltips for the specific object only. It should look like this:
tooltipsCss: {
    fontFamily: 'Verdana',
    fontSize: '20pt'
}
null
tooltipsOffsetxThis property allows you to shift the tooltips left or right. 0
tooltipsOffsetyThis property allows you to shift the tooltips up or down. 0
tooltipsHotspotIgnoreThis can be a number of things and can be used to ignore certain tooltip hotspots - which can allow charts to the rear to be clickable. There's an example of this in the download archive called pie-tooltipshotspotignore.html. You can use the transparent color to allow the rear chart to be seen in such a case. It can be:
  • A single boolean value (ie true or false) to enable or disable all of the hotspots - true means the hotspot will be ignored
  • A single number (the zero-indexed number corresponding to the hotspot to ignore)
  • An array of numbers (the numbers are the indexes of hotspots to ignore)
  • An array of boolean true or false values - the position of these values correspond to the index(es) of the segments to ignore (for example [false, false, true, false, false] - true means the corresponding hotspot will be ignored)
null
contextmenuAn array of context menu items. More information about context menus is here.[] (An empty array)
annotatableWhether annotations are enabled for the chart (ie you can draw on the chart interactively.false
annotatableColorIf you do not allow the use of the palette, then this will be the only color allowed for annotations.black
annotatableLinewidthThis is the linewidth of the annotations.1
adjustable
Defaulting to false, this determines whether your bar chart will be adjustable.
Default: false

tooltips
A numerically indexed array of tooltips that are shown when a bar is clicked. These can contain HTML.
Default: null

tooltipsHighlight
Set this to false if you don't want your charts to be highlighted.
Default: true

tooltipsEffect
The effect used for showing tooltips. Possible values are slide fade or none.
Default: slide

tooltipsEvent
This is the event that triggers the tooltips. It can be either click or mousemove.
Default: onclick

tooltipsOverride
If you wish to handle showing tooltips yourself, this should be a function object which does just that. There's more information on the tooltips documentation page.
Default: null

tooltipsFormattedPoint
When using formatted tooltip strings this is used as the point when using the %{value_formatted} option.
Default: .

tooltipsFormattedThousand
When using formatted tooltip strings this is used as the thousand separator when using the %{value_formatted} option.
Default: ,

tooltipsFormattedDecimals
When using formatted tooltip strings this specifies the number of decimals when using the %{value_formatted} option.
Default: 0

tooltipsFormattedUnitsPre
When using formatted tooltip strings these units are prepended to the number when using the %{value_formatted} option.
Default: (an empty string)

tooltipsFormattedUnitsPost
When using formatted tooltip strings these units are appended to the number when using the %{value_formatted} option.
Default: (an empty string)

tooltipsFormattedKeyColors
When using formatted tooltip strings you can give specific colors for the %{key} option to use.
Default: null

tooltipsFormattedKeyColorsShape
This is the shape that's used in the tooltip key. It can be square or circle
Default: square

tooltipsFormattedKeyColorsCss
By using this property you can add CSS values to the key color shape that appears in the tooltip key. Note the property name is "color" and not "colors" like previous properties. It should be an object of CSS properties like this:
tooltipsFormattedKeyColorsCss : {
    border: "1px solid #ddd";
}

Default: null

tooltipsFormattedKeyLabels
When using formatted tooltip strings these are the labels that are displayed.
Default: [] (an empty array)

tooltipsFormattedListType
With this property you can switch between an unordered list (the default) and an ordered list. Possible values are ul and ol.
Default: ul

tooltipsFormattedListItems
This should be a two-dimension array of the list items that are to be shown for all of the tooltips. An example of this property is:
tooltipsFormattedListItems: [
    ['Bill','Jerry','Berty'], // First tooltip
    ['Gill','Carrie','Lucy'], // Second tooltip
    ['Pob','Nobby','Hilda']   // Third tooltip
]
You can use CSS to style this list - for example:
.RGraph_tooltip ul#rgraph_formatted_tooltips_list li {
    text-align: left;
    color: yellow;
}

Default: null

tooltipsFormattedTableHeaders
When showing a table in the tooltips this can be an array of headers for the table. These are added to the tooltip using th tags.
Default: null

tooltipsFormattedTableData
This is the data that is added to the table. This is a 3-dimensional array so it's easy to make a mistake. See the example, copy the code from it and then modify it suit. You'll create fewer bugs this way.
Default: null)

tooltipsPointer
By default the tooltips have a small triangular pointer that points to the shape that was clicked on. You can turn this off with this property.
Default: true

tooltipsPointerCss
If you want any CSS values applied to the tooltips pointer (a CSS border, for example) then specify an object containing those values to this property. For example:
tooltipsPointerCss: {
    borderLeft: 'gray 2px solid',
    borderBottom: 'gray 2px solid'
}

Default: null

tooltipsPositionStatic
The new default (as of August 2020) is for tooltips to be positioned statically and not be dependent on the mouse position. If you don't want this for whatever reason, you can disable it with this setting. When you set it to false tooltips are positioned next to the mouse pointer.
Default: true

tooltipsCssClass
This is the name of the CSS class the chart uses.
Default: RGraph_tooltip

tooltipsCss
If you want to specify some CSS that gets applied to all of the tooltips, but don't want to use the RGraph.tooltips.style object (which gets applied to all of the tooltips on the page for every chart) you can use this property to give some per-object CSS for the tooltips. These are CSS styles that get applied to all of the tooltips for the specific object only. It should look like this:
tooltipsCss: {
    fontFamily: 'Verdana',
    fontSize: '20pt'
}

Default: null

tooltipsOffsetx
This property allows you to shift the tooltips left or right.
Default: 0

tooltipsOffsety
This property allows you to shift the tooltips up or down.
Default: 0

tooltipsHotspotIgnore
This can be a number of things and can be used to ignore certain tooltip hotspots - which can allow charts to the rear to be clickable. There's an example of this in the download archive called pie-tooltipshotspotignore.html. You can use the transparent color to allow the rear chart to be seen in such a case. It can be:
Default: null

contextmenu
An array of context menu items. More information about context menus is here.
Default: [] (An empty array)

annotatable
Whether annotations are enabled for the chart (ie you can draw on the chart interactively.
Default: false

annotatableColor
If you do not allow the use of the palette, then this will be the only color allowed for annotations.
Default: black

annotatableLinewidth
This is the linewidth of the annotations.
Default: 1

Miscellaneous properties

PropertyDescriptionDefault
highlightStyleBy default this is null but you can set it to a function if you wish so that function is called to do the chart highlighting. It's passed the shape object as an argument.null
cleartoThis is used in animations and effects as the default color to use when clearing the canvas.null
bulbBottomRadiusAdjustIf you want to add or remove a little (or a lot) from the bottom bulb radius you use this (use negative numbers to subtract). 0
bulbBottomRadiusUse this property to set the bottom bulb radius.null
highlightStyle
By default this is null but you can set it to a function if you wish so that function is called to do the chart highlighting. It's passed the shape object as an argument.
Default: null

clearto
This is used in animations and effects as the default color to use when clearing the canvas.
Default: null

bulbBottomRadiusAdjust
If you want to add or remove a little (or a lot) from the bottom bulb radius you use this (use negative numbers to subtract).
Default: 0

bulbBottomRadius
Use this property to set the bottom bulb radius.
Default: null

Methods

obj.get(name)
An accessor that you can use to retrieve the values of properties.

obj.set(name, value)
An accessor that you can use to set the values of properties.

obj.getShape(event)
This method makes it easy to get hold of the bar when it's been clicked on or hovered over. It returns an object which has the following indexes available:
object The chart object.
x The X coordinate of the main body of the Thermometer.
y The Y coordinate of the main body of the Thermometer.
width The width of the main body of the Thermometer.
height The height of the main body of the Thermometer.
dataset As there's only ever one element on the Thermometer chart this is always zero.
index As there's only ever one element on the Thermometer chart this is always zero.
sequentialIndex As there's only ever one element on the Thermometer chart this is always zero.
tooltip If a tooltip is associated with the Thermometer this will be it.id: strings are expanded for you (where the tooltip text is retrieved from the CHTML tag with the matching ID).
<script>
    thermometer.canvas.onclick = function (e)
    {
        RGraph.redraw();
    
        var canvas = e.target,
            obj    = canvas.__object__,
            shape  = obj.getShape(e);

        if (shape) {            
            // Highlight the main body of the Thermometer chart. If you need to
            // highlight the whole of the Thermometer chart you can use the highlight
            // function: obj.highlight(shape)
            obj.path(
                'lw 10 b r % % % % s black f red',
                shape.x, shape.y, shape.width, shape.height
            );
        }
    }
</script>

obj.getValue(mixed)

This method can be used to get the value at a particular point or at the mouse coordinates based on the scale that is in use. Not simply the coordinates of the mouse. The argument can either be an event object (for use in event listener functions) OR a two-element array consisting of the X and Y coordinates (ie when you're not necessarily in an event listener). It returns null if the mouse or coordinates are in the margin areas. An example:

myChart.canvas.onclick = function (e)
{
    var obj   = e.target.__object__;
    var value = obj.getValue(e);
    
    // ...
}

obj.getYCoord(value)

This method can be used to get an appropriate Y coordinate for a value when you're doing custom drawing on the chart. It returns null if the value is out of range.


obj.on(event, function)

This method can be used to set an event listener on an object. It operates similarly to the jQuery on function. The first argument is the event that you wish to attach to and the second is the handler function. For example:

obj.on('draw', function (obj)
{
    // Put your event code here
});

The function is useful if you use method chaining when creating your charts:

var obj = new RGraph.Thermometer({
    id: 'cvs',
    min: 0,
    max: 100,
    value: 56,
    options: {
    }
}).on('draw', function (obj)
{
    // Put your draw event code here

}).on('click', function (e, shape)
{
    // Handle the click event

}).draw();
obj.exec(function)

The exec function is documented here.

obj.responsive(configuration)

The responsive function helps your charts respond to different browser window sizes and screen resolutions. For example, for smaller screens, you might want to have angled labels or show shorter versions of them completely.

The responsive function is documented on its own page here.

Events

RGraph supports custom events that allow you to easily add interactivity to your charts if required. The following events are available:

For example:
new RGraph.Thermometer({
    id: 'cvs',
    min: 0,
    max: 100,
    value: 56,
    options: {
    }
}).on('draw', function (obj)
{
    console.log('The draw event has fired');
    
}).draw();

Effects

These effects are available and can be used instead of the draw function. There are also generic effects that are available which you can see here: Generic effects and transitions
<script>
    // Optional callback function that's called when the effect is complete
    function myCallback (obj)
    {
        // ...
    }

    new RGraph.Thermometer({
        id: 'cvs',
        min: 0,
        max: 100,
        value: 56,
        options: {
            marginLeft: 35
        }
    }).grow({frames: 60}, myCallback)
</script>