Canvas Thermometer chart API reference

Documentation about the Thermometer chart including information on all the options available to you. Thermometer charts can be used in a similar fashion to the Vertical Progress bar - they just have a different asthetic.

 

Example

<script>
    var thermometer = new RGraph.Thermometer({
        id: 'cvs',
        min: 0,
        max: 100,
        value: 14,
        options: {
            marginLeft: 45,
            marginRight: 45,
            colors: ['rgba(255,0,0,1)']
        }
    }).draw();
</script>

The example pages are here.

 

Properties

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

Margin properties

PropertyDescriptionDefault
marginLeftThe left margin of the chart, (the margin is where the labels and title are)).25
marginRightThe right margin of the chart, (the margin is where the labels and title are).25
marginTopThe top margin of the chart, (the margin is where the labels and title are).25
marginBottomThe bottom margin of the chart, (the margin is where the labels and title are).25

Color properties

PropertyDescriptionDefault
colorsAn array of the colors of the bars.['Gradient(#c00:red:#f66:#fcc)']
colorsStrokeThe color of the border around the thermometerblack
colorsBackgroundThe default background colorwhite

Title properties

PropertyDescriptionDefault
titleSideThis is the text that is used as the side title on the left hand side of the thermometer.An empty string
titleSideFontThe font that the title is rendered in. If not specified the text.font setting is used (usually Arial)null
titleSideSizeThe size of the title. If not specified the size is usually 2pt bigger than the text.size setting.null
titleSideBoldWhather the title is bold or not.true

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>
true
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 in text.true
labelsValueDecimalsThis controls how many decimals are shown if the value is being shown. It falls back to use scale.decimals 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
labelsCountA value that controls how many Y 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 scale.decimals.5

Shadow properties

PropertyDescriptionDefault
shadowWhether a drop shadow is applied.true
shadowColorThe color of the shadow.gray
shadowOffsetxThe X offset of the shadow.0
shadowOffsetyThe Y offset of the shadow.0
shadowBlurThe severity of the shadow blurring effect.15

Scale properties

PropertyDescriptionDefault
scaleVisibleDefaulting to false, this controls whether the scale is visible.false
scaleDecimalsThis allows you to control the amount of decimals that the labels have.0
scalePointThe character used as the decimal point..
scaleThousandThe character used as the thousand separator,
scaleUnitsPreThe units that the Y axis is measured in. This string is displayed BEFORE the actual 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 actual number, allowing you to specify values such as "50ms".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. Can be either fade or none.fade
tooltipsEventThis is the event that triggers the tooltips. It can be either onclick or onmousemove.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 pagenull
tooltipsNohideonclearNot an option that you'll need particularly often if at all. Setting this to true means that when you call the RGraph.clear() API function tooltip DO NOT get hidden.false
contextmenuAn array of context menu items. More information on context menus is here.[] (An empty array)
resizableDefaulting to false, this determines whether your chart will be resizable. Because of the numerous event handlers this has to install code on, This feature is unlikely to work with other dynamic features (the context menu is fine however).false
resizableMinwidthThis allows you to set a minimum width that the chart can be resized to.null
resizableMinheightThis allows you to set a minimum height that the chart can be resized to.null
resizableMaxwidthThis allows you to set a maximum width that the chart can be resized to.null
resizableMaxheightThis allows you to set a maximum height that the chart can be resized to.null
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 colour allowed for annotations.black
annotatableLinewidthThis is the line width of the annotations.1

Zoom properties

PropertyDescriptionDefault
zoomFactorThis is the factor that the chart will be zoomed by (bigger values means more zoom)1.5
zoomFadeInWhether the zoomed canvas fades in or not. This also can be used to control the fade in for the zoom in thumbnail mode.true
zoomFadeOutWhether the zoomed canvas fades out or not. This also can be used to control the fade in for the zoom in thumbnail mode.true
zoomHdirThe horizontal direction of the zoom. Possible values are: left, center, rightright
zoomVdirThe vertical direction of the zoom. Possible values are: up, center, downdown
zoomDelayThe delay (in milliseconds) between frames.50
zoomFramesThe number of frames in the zoom animation.10
zoomShadowWhether or not the zoomed canvas has a shadow or not.true

Event properties

PropertyDescriptionDefault
eventsClickIf you want to add your own onclick function you can do so by assigning it to this property. See here for details.null
eventsMousemoveIf you want to add your own onmousemove function you can do so by assigning it to this property. See here for details.null
eventsMouseoverIf you want to add your own onmouseover function you can do so by assigning it to this property. See here for details.null
eventsMouseoutIf you want to add your own onmouseout function you can do so by assigning it to this property. See here for details.null

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. Its 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

 

Methods

 

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

 

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

 

obj.getShape(event)

This method returns details on the focused bar (there's only one). It returns an array consisting of:

The shape also includes textual indexes like this: shape['object'] And they are:

 

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, func)

This method can be used to set an event listener on an object. It operates in a similar way to the jQuery .on() function - the first argument is the event you wish to attach to and the second is the handler function. For example:

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

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

var obj = new RGraph.Thermometer('cvs', 0,100,56)
    .on('draw', function (e, shape)
    {
        // Put ondraw code here
    })
    .on('click', function (e, shape)
    {
        // Handle click event
    })
    .draw()

 

The exec option and method

The exec function is documented here.

 

Animation effects

These effects are available and can be used instead of the .draw() function. There are also generic effects 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)
    {
        // ...
    }

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