Thermometer chart API reference

• Example
• Properties
• Methods
• The coordinates properties
• Events
• Effects

Example

<script>
    new RGraph.Thermometer({
        id: 'cvs',
        min: 0,
        max: 100,
        value: 52,
        options: {
            colors: ['Gradient(red:#f33:red)'],
            marginLeft: 35,
            marginRight: 35,
            tooltips: 'Todays temperature
%{key}',
            tooltipsFormattedKeyLabels: ['London'],
            tooltipsFormattedUnitsPost: 'c',
            tooltipsCss: {
                fontSize: '18pt',
                textAlign: 'left'
            }
        }
    }).draw();
</script>

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
• Background properties
• Color properties
• Title properties
• Labels and text properties
• Shadow properties
• Scale properties
• Interactive features properties
• Miscellaneous properties

<div style="margin-left: 50px; display: inline-block">
    <canvas id="cvs" width="650" height="250"></canvas>
</div>

tooltipsFormattedKeyColorsCss : {
    border: "1px solid #ddd";
}

tooltipsFormattedListItems: [
    ['Bill','Jerry','Berty'], // First tooltip
    ['Gill','Carrie','Lucy'], // Second tooltip
    ['Pob','Nobby','Hilda']   // Third tooltip
]

.RGraph_tooltip ul#rgraph_formatted_tooltips_list li {
    text-align: left;
    color: yellow;
}

tooltipsPointerCss: {
    borderLeft: 'gray 2px solid',
    borderBottom: 'gray 2px solid'
}

tooltipsCss: {
    fontFamily: 'Verdana',
    fontSize: '20pt'
}

Methods

<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>

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);
    
    // ...
}

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.

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();

The exec function is documented here.

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.

Update: There is now the responsive configuration option available to you and this is now the preferred method of configuration.

The responsive function and configuration option are documented on their own page here.

The coordinates properties

There's only one coordinates property with the Thermometer chart because there's only one selectable area - the vertical indicator bar. This doesn't include the round bell of the Thermometer chart.

• obj.coords These are the coordinates (a rectangle) that make up the indicator bar (the round bell of the thermometer is n't included. The coordinates are just the standard rect coords though it is a two-dimensioned array to keep it consistent with other charts:
  • x
  • y
  • width
  • height
  So you can access the coordinates like this:

  var x      = obj.coords[0][0],
      y      = obj.coords[0][1],
      width  = obj.coords[0][2],
      height = obj.coords[0][3];
  

• obj.coordsText This holds the coordinates of all of the text that has been added to the chart. Even if the text is blank (ie no text) then the coordinates will be added to this variable.

Events

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

• adjustbegin This event fires at the start of adjusting - like the standard mousedown event.
• adjust This event fires (repeatedly) during adjusting - like the standard mousemove event.
• adjustend This event fires at the end of adjusting - like the standard mouseup event.
• annotatebegin This event fires at the start of annotating - like the standard mousedown event.
• annotate This event fires (repeatedly) during annotating - like the standard mousemove event.
• annotateend This event fires at the end of annotating - like the standard mouseup event.
• annotateclear This event fires at the end of the RGraph.clearAnnotations function.
• beforeclear This event fires at the start of the RGraph.clear function.
• clear This event fires at the end of the RGraph.clear function.
• click This is similar to the standard canvas click event but this only fires when you click on a bar - not the whole canvas.
• beforecontextmenu This event fires when you have the contextmenu enabled and it is about to appear.
• contextmenu This event fires when you have the contextmenu enabled and it has been displayed.
• beforedraw This event fires at the start of the draw method before anything has been done.
• firstdraw This event fires at the end of the draw function - but only the first time that the draw function is called.
• draw This event fires at the end of the draw function.
• mousemove This event is similar to the standard mousemove event but only fires when you move the mouse over a bar on the chart.
• mouseover This event is similar to the standard mouseover event but only fires when you move the mouse over a bar on the chart.
• mouseout This event is similar to the standard mouseout event but only fires when you move the mouse away from a bar on the chart that you've previously hovered over.
• beforetooltip This event fires at the start of the tooltip showing process.
• tooltip This event fires after a tooltip has been shown.

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

There's a stopAnimation() function that you can use to stop an animation immediately if you need to. There's a line chart demo called demos/line-effects-stop-animation.html in the download archive that demonstrates the use of this function.

• The grow effect(effects-thermometer-grow.html in the download archive)

<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>