Google Charts - Configuration Syntax


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In this chapter we'll showcase the configuration required to draw a chart using Google Chart API.

Step 1: Create HTML Page

Create an HTML page with the Google Chart libraries.

googlecharts_configuration.htm

<html>
   <head>
      <title>Google Charts Tutorial</title>
      <script type = "text/javascript" src = "https://www.gstatic.com/charts/loader.js">
      </script>
      <script type = "text/javascript">
         google.charts.load('current', {packages: ['corechart']});     
      </script>
   </head>
   
   <body>
      <div id = "container" style = "width: 550px; height: 400px; margin: 0 auto">
      </div>
   </body>
</html>

Here container div is used to contain the chart drawn using Google Chart library. Here we are loading the latest version of corecharts API using google.charts.load method.

Step 2: Create configurations

Google Chart library uses very simple configurations using json syntax.

// Instantiate and draw the chart.
var chart = new google.visualization.PieChart(document.getElementById('container'));
chart.draw(data, options);

Here data represents the json data and options represents the configuration which Google Chart library uses to draw a chart withing container div using draw() method. Now we'll configure the various parameter to create the required json string.

title

Configure the options of the chart.

// Set chart options
var options = {'title':'Browser market shares at a specific website, 2014',
   'width':550,
   'height':400};

DataTable

Configure the data to be displayed on the chart. DataTable is a special table structured collection which contains the data of the chart. Columns of data table represents the legends and rows represents the corresponding data. addColumn() method is used to add a column where first parameter represents the data type and second parameter represents the legend. addRows() method is used to add rows accordingly.

// Define the chart to be drawn.
var data = new google.visualization.DataTable();
data.addColumn('string', 'Browser');
data.addColumn('number', 'Percentage');
data.addRows([
   ['Firefox', 45.0],
   ['IE', 26.8],
   ['Chrome', 12.8],
   ['Safari', 8.5],
   ['Opera', 6.2],
   ['Others', 0.7]
]);

Step 3: Draw the chart

// Instantiate and draw the chart.
var chart = new google.visualization.PieChart(document.getElementById('container'));
chart.draw(data, options);

Example

Following is the complete example −

googlecharts_configuration.htm

Live Demo
<html>
   <head>
      <title>Google Charts Tutorial</title>
      <script type = "text/javascript" src = "https://www.gstatic.com/charts/loader.js">
      </script>
      <script type = "text/javascript">
         google.charts.load('current', {packages: ['corechart']});     
      </script>
   </head>
   
   <body>
      <div id = "container" style = "width: 550px; height: 400px; margin: 0 auto">
      </div>
      <script language = "JavaScript">
         function drawChart() {
            // Define the chart to be drawn.
            var data = new google.visualization.DataTable();
            data.addColumn('string', 'Browser');
            data.addColumn('number', 'Percentage');
            data.addRows([
               ['Firefox', 45.0],
               ['IE', 26.8],
               ['Chrome', 12.8],
               ['Safari', 8.5],
               ['Opera', 6.2],
               ['Others', 0.7]
            ]);
               
            // Set chart options
            var options = {'title':'Browser market shares at a specific website, 2014', 'width':550, 'height':400};

            // Instantiate and draw the chart.
            var chart = new google.visualization.PieChart(document.getElementById ('container'));
            chart.draw(data, options);
         }
         google.charts.setOnLoadCallback(drawChart);
      </script>
   </body>
</html>

Following code call drawChart function to draws chart when Google Chart library get loaded completely.

google.charts.setOnLoadCallback(drawChart);

Result

Verify the result.



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