Gauge chart API reference

• Example
• The obj.nodes property
• Properties
• Methods
• Events

Example

<script>
    new RGraph.SVG.Gauge({
        id: 'chart-container',
        innerMin: 0,
        innerMax: 10,
        outerMin: 0,
        outerMax: 100,
        value: 7.8,
        options: {
            adjustable: true,
            centerpinRadius: 10,
            labelsIngraphUnitsPost: '%',
            labelsIngraphDecimals: 1,
            colors: ['red','blue'],
            marginTop: 15,
            marginBottom: 15,
            marginLeft: 15,
            marginRight: 15
        }
    }).draw();
</script>

The obj.nodes property

Instead of coordinates the Gauge chart maintains references to the nodes that are created - such as the axes, the labels and text nodes. For example:

• obj.nodes.background
• obj.nodes.labelsIngraph
• obj.nodes.labelsIngraphGroup
• obj.nodes.needleGroup
• obj.nodes.innerAxis
• obj.nodes.innerAxisGroup
• obj.nodes.outerAxis
• obj.nodes.outerAxisGroup

For example, you could add your own event listeners like this:

<script>
    obj.nodes.needleGroup.onclick = function (e)
    {
        alert('The value is: ' + obj.value);
    }
</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.

• Chart configuration properties
• Margin properties
• Background properties
• Color properties
• Other text properties
• Scale properties
• Title properties
• Tickmark properties
• Other properties

Methods

obj.get(name)

This can be used to get properties if necessary. It's normally used after the chart is drawn if you need to get parameters (if you're doing custom coding for example).

obj.set(name, value)

This can be used to set properties if necessary. It's normally used after the chart is drawn if you need to set additional parameters or change them.

obj.on(event, handler)

This function adds an event listener (such as beforedraw or draw) to the chart object. For example:

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

obj.exec(func)

This function can be used to execute a function (immediately). It's not event-based (ie it doesn't run when something happens) - it just runs immediately - and only once. You might use it when you need to get something from the chart when it's drawn and then call the redraw function. Because this function only runs once the RGraph.SVG.redraw function would not cause a loop - which would happen if you used the draw event.

obj.exec(function (obj)
{
    // Put your code 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.

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.

Events

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

• beforedraw This event fires at the start of the draw method before anything has been done.
• draw This event fires at the end of the draw function.
• firstdraw This event fires at the end of the draw function - but only the first time and so it fires only once after the first draw call.
• adjustbegin This event fires at the start of adjusting.
• adjust This event fires (repeatedly) during adjusting.
• adjustend This event fires at the end of adjusting.

For example:

new RGraph.SVG.Gauge({
    id: 'chart-container',
    innerMin: 0,
    innerMax: 100,
    outerMin: 0,
    outerMax: 10,
    value: 78,
    options: {
    }
}).on('draw', function (obj)
{
    console.log('The draw event has fired');
    
}).draw();