Change Chart Type at Runtime
FusionCharts Suite XT includes advanced features that let you add more context to your chart and make data visualization simpler. These features include chart updates, update chart type at runtime, and events.
This article focuses on how you can change the chart type of the chart at runtime using a Python function
. The chart types used in the sample is:
Column 2D
Bar 2D
Pie 2D
A chart configured to change the chart type is shown below:
{
"chart": {
"caption": "Countries With Most Oil Reserves [2017-18]",
"subCaption": "In MMbbl = One Million barrels",
"xAxisName": "Country",
"yAxisName": "Reserves (MMbbl)",
"numberSuffix": "K",
"theme": "fusion"
},
"data": [
{
"label": "Venezuela",
"value": "290"
},
{
"label": "Saudi",
"value": "260"
},
{
"label": "Canada",
"value": "180"
},
{
"label": "Iran",
"value": "140"
},
{
"label": "Russia",
"value": "115"
},
{
"label": "UAE",
"value": "100"
},
{
"label": "US",
"value": "30"
},
{
"label": "China",
"value": "30"
}
]
}
The full code for the above sample is given below:
from django.shortcuts import render
from django.http import HttpResponse
# Include the `fusioncharts.py` the file which has required functions to embed the charts in HTML page
from ..fusioncharts import FusionCharts
# Loading Data from a Static JSON String
# It is an example to show how to attach event in the chart.
# The `chart` method is defined to load chart data from a JSON string.
def chart(request):
# Create an object for the column2d chart using the FusionCharts class constructor
column2d = FusionCharts("column2d", "ex1", '700', '400', "chart-1", "json",
# The chart data is passed as a string to the `dataSource` parameter.
"""{
"chart":
{
"caption": "Countries With Most Oil Reserves [2017-18]",
"subCaption": "In MMbbl = One Million barrels",
"xAxisName": "Country",
"yAxisName": "Reserves (MMbbl)",
"numberSuffix": "K",
"theme": "fusion"
},
"data": [{
"label": "Venezuela",
"value": "290"
}, {
"label": "Saudi",
"value": "260"
}, {
"label": "Canada",
"value": "180"
}, {
"label": "Iran",
"value": "140"
}, {
"label": "Russia",
"value": "115"
}, {
"label": "UAE",
"value": "100"
}, {
"label": "US",
"value": "30"
}, {
"label": "China",
"value": "30"
}]
}""")
# returning complete JavaScript and HTML code, which is used to generate chart in the browsers.
return render(request, 'dynamic-chart-type.html', {'output' : column2d.render(), 'chartTitle': 'Dynamic Chart Type Change'})
The HTML template to render the above chart is shown below:
<!DOCTYPE html>
<html>
<head>
<title>FC-python wrapper</title>
<!-- If you are using downloaded FusionCharts libraries, uncomment the below code -->
<script type="text/javascript" src="//cdn.fusioncharts.com/fusioncharts/latest/fusioncharts.js"></script>
<script type="text/javascript" src="//cdn.fusioncharts.com/fusioncharts/latest/themes/fusioncharts.theme.fusion.js"></script>
</head>
<body style="font-family:'Helvetica Neue', Arial; font-size: 16px;">
<h3>{{ chartTitle|safe }}</h3>
<script type="text/javascript">
FusionCharts && FusionCharts.ready(function () {
var trans = document.getElementById("controllers").getElementsByTagName("input");
for (var i=0, len=trans.length; i<len; i++) {
if (trans[i].type == "radio"){
trans[i].onchange = function() {
changeChartType(this.value);
};
}
}
});
function changeChartType(chartType) {
for (var k in FusionCharts.items) {
if (FusionCharts.items.hasOwnProperty(k)) {
FusionCharts.items[k].chartType(chartType);
}
}
};
</script>
<div align="center">
<label style="padding: 0px 5px !important;">Select The Chart Type</label>
</div>
<br/>
<div id="controllers" align="center" style="font-family:'Helvetica Neue', Arial; font-size: 14px;">
<label style="padding: 0px 5px !important;">
<input type="radio" name="div-size" checked value="column2d"/>Column 2D
</label>
<label style="padding: 0px 5px !important;">
<input type="radio" name="div-size" value="pie3d"/>Pie 3D
</label>
<label style="padding: 0px 5px !important;">
<input type="radio" name="div-size" value="bar2d"/>Bar 2D
</label>
</div>
<br/>
<br/>
<br/>
<div style="width: 100%; display: block;" align="center">
<div id="chartContainer">{{ output|safe }}</div>
</div>
<br/>
<br/>
<a href="/">Go Back</a>
</body>
</html>
The sample code provided above corresponds to the following tasks:
Import and resolve dependencies:
render
fromdjango.shortcuts
, andHttpResponse
fromdjango.http
FusionCharts
fromfusioncharts
Define a function
chart
, which takesrequest
as an argument:Create a variable
column2d
, which is an instance of theFusionCharts
class. As argument values forFusionCharts
, pass the chart details and the configuration (JSON string):Set the chart
type
ascolumn2d
. Find the complete list of chart types with their respective alias here .Set the
id
asex1
.Set the
width
andheight
of the chart in pixels. You can also provide them as percentages.Set the
renderAt
aschart-1
.Set the
dataFormat
asjson
.Embed the json data (string) as the value of
dataSource
.
Return the output of the
render
function (defined inFusionCharts
):Pass the
request
, which is also the only argument accepted by thechart
function you are defining.Pass the relative path of the HTML template, where the chart will be rendered.
Pass a dictionary:
Set the
output
tocolumn2d.render()
.Set the
chartTitle
toExample of event (product life cycle event)
.
When you change the values of
id
andrenderAt
, ensure that the corresponding changes are reflected in the HTML template. The string values forrenderAt
in the code, and the correspondingdiv id
in the HTML template, should be the exact same.
Refer to Column 2D chart for more information on the configuration and data for this chart type. Alternatively, if your starting chart is Bar chart or Pie chart , you can use their respective pages as a source of detailed information for possible configuration and data.