The drawing API Image object API reference

• Usage example
• Properties
• Methods

The image object allows you to add images to your charts. The image can, for example, be used as a way to provide an extra tooltip to your users or it can be used as a background image instead of using the built-in backgroundImage option.

The advantage, in this case, is that by using the image drawing object as the background image instead of specifying a background image for the Line chart (which you can do with the backgroundImage option) is that you can click the background and have the click event triggered or show a tooltip.

Usage example

<script>
    new RGraph.Line({
        id: 'cvs',
        data: [4,9,1,3,2,6,5],
        options: {
            xaxisLabels: ['Mon','Tue','Wed','Thu','Fri','Sat','Sun'],
            marginInner: 5,
            tickmarksStyle: 'endcircle',
            colors: ['black'],
            tooltips: ['A','B','C','D','E','F','G'],
            marginBottom: 35,
            textSize: 10
        }
    }).draw();

    image = new RGraph.Drawing.Image({
        id: 'cvs',
        x: 40,
        y: 40,
        src: '/images/logo.png', // CHANGE THIS TO AN IMAGE ON YOUR WEBSITE
        options: {
            width: 32,
            height: 32,
            tooltips: ['Your logo!'],
            textSize: 10
        }
    }).draw();
</script>

Properties

• Configuration properties
• Background properties
• Color properties
• Shadow properties
• Interactive features properties
• Border properties
• Labels and text properties
• Miscellaneous properties

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;
}

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

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

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

Methods

<script>
    image.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 Image object.
            obj.path(
                'lw 10 b r % % % % s black f rgba(255,0,0,0.25)',
                shape.x, shape.y, shape.width, shape.height
            );
        }
    }
</script>

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.Drawing.Image({
    id: 'cvs',
    x: 64,
    y: 64,
    src: '/images/logo.png',
}).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.