Configuring your Chart using django

FusionCharts Suite XT includes advanced features that let you add more context to your chart and makes data visualization simpler. These features include updating chart data, annotations, trend-lines, and events.

This article focuses on how you can configure your charts using Python functions (which you can call from elsewhere), to perform the following:

Update Chart Data

A chart, configured to update data values dynamically, is shown below:

FusionCharts will load here..
{
    "chart": {
        "caption": "Customer Satisfaction Score",
        "subcaption": "Los Angeles Topanga",
        "plotToolText": "Current Score: $value",
        "theme": "fusion",
        "chartBottomMargin": "50",
        "showValue": "1"
    },
    "colorRange": {
        "color": [
            {
                "minValue": "0",
                "maxValue": "90",
                "code": "#e44a00"
            },
            {
                "minValue": "90",
                "maxValue": "150",
                "code": "#f8bd19"
            },
            {
                "minValue": "150",
                "maxValue": "250",
                "code": "#6baa01"
            }
        ]
    },
    "dials": {
        "dial": [
            {
                "value": "70",
                "id": "dial1"
            }
        ]
    }
}

The full code for the above sample is given below:

from django.shortcuts import render
from django.http import HttpResponse

# Include the `fusioncharts.py` file that contains functions to embed the charts.
from ..fusioncharts import FusionCharts

# Loading Data from a Static JSON String
# Example to create an Angular Gauge with the chart data passed as JSON string format.
# The `chart` method is defined to load chart data from a JSON string.

def chart(request):

    # Create an object for the angualar gauge using the FusionCharts class constructor
    angularGauge = FusionCharts("angulargauge", "ex1" , "700", "400", "chart-1", "json", 
        # The data is passed as a string in the `dataSource` as parameter.
        """{  
            "chart": { 
                "caption": "Customer Satisfaction Score", 
                "subcaption": "Los Angeles Topanga", 
                "plotToolText": "Current Score: $value", 
                "theme": "fusion", 
                "chartBottomMargin": "50", 
                "showValue": "1" 
            }, 
            "colorRange": { 
                "color": [{ 
                    "minValue": "0", 
                    "maxValue": "90", 
                    "code": "#e44a00"
                }, { 
                    "minValue": "90", 
                    "maxValue": "150", 
                    "code": "#f8bd19" 
                }, { 
                    "minValue": "150", 
                    "maxValue": "250", 
                    "code": "#6baa01" 
                }] 
            }, 
            "dials": { 
                "dial": [{ 
                    "value": "70", 
                    "id": "dial1" 
                }] 
            }
        }"""
        )
    # returning complete JavaScript and HTML code, which is used to generate chart in the browsers.
    return  render(request, 'update-data-runtime.html', {'output' : angularGauge.render(),'chartTitle': 'Update data at runtime'})

The HTML template to render the above chart is given below:

<!DOCTYPE html>
<html>
<head>
    <title>FC-python wrapper</title>
   <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>
    <script>
        updateData = function () {
           var value = document.getElementById("dial-val").value;
           FusionCharts("ex1").setDataForId("dial1", value);
       }
    </script>
</head>
<body style="font-family:'Helvetica Neue', Arial; font-size: 16px;">
    <h3>{{ chartTitle|safe }}</h3>
    <div id="chart-1">{{ output|safe }}</div>
    <br/>
    <div>
    <label for="dial-val">Input dial value</label>
    <input name="dial-val" id="dial-val" type= "number"/>
    <input type ="button" name ="update dial" value ="update dial" onclick ="updateData()" />
    </div>
    <br/>
    <a href="/">Back</a>
</body>
</html>

The sample code provided above corresponds to the following tasks:

  1. Import and resolve dependencies:

    • render from django.shortcuts, and HttpResponse from django.http

    • FusionCharts from fusioncharts

  2. Define a function chart, which takes request as an argument:

    • Create a variable angularGauge, which is an instance of the FusionCharts class. As argument values for FusionCharts, pass the chart details and the configuration (JSON string):

      • Set the chart type as angularGauge. Find the complete list of chart types with their respective alias here.

      • Set the id as ex1.

      • Set the width and height of the chart in pixels. You can also provide them as percentages.

      • Set the renderAt as chart-1.

      • Set the dataFormat as json.

      • Embed the json data (string) as the value of dataSource.

    • Return the output of the render function (defined in FusionCharts):

      • Pass the request, which is also the only argument accepted by the chart function you are defining.

      • Pass the relative path of the HTML template, where the chart will be rendered.

      • Pass a dictionary:

        • Set the output to angularGauge.render().

        • Set the chartTitle to Update data at runtime.

When you change the values of id and renderAt, ensure that the corresponding changes are reflected in the HTML template. The string values for renderAt in the code, and the corresponding div id in the HTML template, should be the exact same.

Refer to Angular Gauge for more information on the configuration and data for this chart type.

Update Chart Attributes

A chart configured to update the chart caption, sub-caption alignment, and chart background dynamically is shown below.

FusionCharts will load here..
{
    "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 a Column 2D chart where data is passed as JSON string format.
# 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, 'update-data-runtime.html', {'output' : angularGauge.render(),'chartTitle': 'Update data at runtime'})

The HTML template to render the above chart is shown below:

<!DOCTYPE html>
<html>
<head>
  <title>FC-python wrapper</title>
  <style>
    .button {
      display:inline-block;
      margin:5px;
      padding: 4px 12px;
      margin-bottom: 0;
      font-size: 14px;
      line-height: 20px;
      color: #333;
      text-align: center;
      text-shadow: 0 1px 1px rgba(255,255,255,0.75);
      vertical-align: middle;
      cursor: pointer;
      background-color: #f5f5f5;
      background-image: -moz-linear-gradient(top,#fff,#e6e6e6);
      background-image: -webkit-gradient(linear,0 0,0 100%,from(#fff),to(#e6e6e6));
      background-image: -webkit-linear-gradient(top,#fff,#e6e6e6);
      background-image: -o-linear-gradient(top,#fff,#e6e6e6);
      background-image: linear-gradient(to bottom,#fff,#e6e6e6);
      background-repeat: repeat-x;
      border: 1px solid #ccc;
      border-color: #e6e6e6 #e6e6e6 #bfbfbf;
      border-color: rgba(0,0,0,0.1) rgba(0,0,0,0.1) rgba(0,0,0,0.25);
      border-bottom-color: #b3b3b3;
      filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffffffff',endColorstr='#ffe6e6e6',GradientType=0);
      filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
      -webkit-box-shadow: inset 0 1px 0 rgba(255,255,255,0.2),0 1px 2px rgba(0,0,0,0.05);
      -moz-box-shadow: inset 0 1px 0 rgba(255,255,255,0.2),0 1px 2px rgba(0,0,0,0.05);
      box-shadow: inset 0 1px 0 rgba(255,255,255,0.2),0 1px 2px rgba(0,0,0,0.05);
    }
  </style>

  <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>
  <script>
    changeBackground = function(e){
      FusionCharts("ex1").setChartAttribute('bgColor', '#efefef');
    }
    changeCaption = function(){
      FusionCharts("ex1").setChartAttribute('captionAlignment', 'left');
    }
    reset = function(e){
      FusionCharts("ex1").setChartAttribute('captionAlignment', 'center');
      FusionCharts("ex1").setChartAttribute('bgColor', '#ffffff');
    }
  </script>
</head>
<body style="font-family:'Helvetica Neue', Arial; font-size: 16px;">
  <h3>{{ chartTitle|safe }}</h3>
  <div align="center"  id="chart-1">{{ output|safe }}</div>
  <br/>
  <div>
    <p align="center" id ="message"></p>
  </div>
  <div id="controllers" align="center" style="font-family:'Helvetica Neue', Arial; font-size: 14px;">
    <input type="button" class="button" onClick="changeBackground()" value='Change Chart Background'/>
    <input type="button" class="button" onClick="changeCaption()" value='Make Caption Text Left Aligned'/>
    <input type="button" class="button" onClick="reset()" value='Reset Attributes'/>
  </div>
</body>
</html>

The sample code provided above corresponds to the following tasks:

  1. Import and resolve dependencies:

    • render from django.shortcuts, and HttpResponse from django.http

    • FusionCharts from fusioncharts

  2. Define a function chart, which takes request as an argument:

    • Create a variable column2d, which is an instance of the FusionCharts class. As argument values for FusionCharts, pass the chart details and the configuration (JSON string):

      • Set the chart type as column2d. Find the complete list of chart types with their respective alias here.

      • Set the id as ex1.

      • Set the width and height of the chart in pixels. You can also provide them as percentages.

      • Set the renderAt as chart-1.

      • Set the dataFormat as json.

      • Embed the json data (string) as the value of dataSource.

    • Return the output of the render function (defined in FusionCharts):

      • Pass the request, which is also the only argument accepted by the chart function you are defining.

      • Pass the relative path of the HTML template, where the chart will be rendered.

      • Pass a dictionary:

        • Set the output to column2d.render().

        • Set the chartTitle to Updating chart properties at runtime.

When you change the values of id and renderAt, ensure that the corresponding changes are reflected in the HTML template. The string values for renderAt in the code, and the corresponding div 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.