Google charts on visualforce page

Here we are taking the url of google chart and assigning dynamic data to the google chart.

Here we are displaying account type and their count.

Controller:

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public class googleChartController {

private String chartData;

public String getChartData()

{

 return chartData;

}

//Contructor

public googleChartController ()

{

 //get obtain a list of picklist values

 Schema.DescribeFieldResult F = Account.Type.getDescribe();

 List<Schema.PicklistEntry> P = F.getPicklistValues();

 //where chart data should be stored.

 List<ChartDataItem> items = new List<ChartDataItem>();

 //iterate through each picklist value and get number of accounts

 // I wish we could do GROUP BY in SOQL!

 for(Schema.PicklistEntry pValue : P)

 {

    integer Count = [select count() from Account where Type = :pValue.getValue() limit 10000];

    if (Count > 0)

      items.add(new ChartDataItem(pValue.getValue()+ '-['+ Count.format() + ']' , Count.format()));

 }

 //Prepare the chart URL

 //String chartPath = 'http://chart.apis.google.com/chart?chs=600x200&cht=p3';

 String chartPath='//chart.googleapis.com/chart?chs=600x200&cht=p3&chco=7777CC|76A4FB|3399CC|3366CC';

 chartData = chartPath +  getChartData(items);

}

private String getChartData(List<ChartDataItem> items)

{

 String chd = ''; //23,34,56

 String chl = ''; //Hello|World

 for(ChartDataItem citem : items)

 {

    chd += citem.ItemValue + ',';

    chl += citem.Label + '|';

 }

 //remove the last comma or pipe

 chd = chd.substring(0, chd.length() -1);

 chl = chl.substring(0, chl.length() -1);

 String result = '&chd=t:' + chd + '&chl=' + chl;

 return result;

}// end of method

public class ChartDataItem

{

 public String ItemValue {  get;  set; }

 public String Label {   get;   set; }

 public ChartDataItem(String Label, String Value)

 {

    this.Label = Label;

    this.ItemValue = Value;

  }

 }

}// end of class

=-==================

VF page

================

<apex:page controller="googleChartController" tabStyle="Account">

<apex:sectionHeader title=" Type of Account"></apex:sectionHeader>

<apex:image url="{!chartData}"></apex:image>

</apex:page>

Output:

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