Wrapper Class in Apex/Visual force page

Wrapper class is a very powerful concept that can be used in multiple scenarios. Putting aside the word "Wrapper" it is nothing but just a class.Just like what we have in a class ,we  have methods,Properties etc in a wrapper class too.Here is an use case for wrapper class

Requirement : A Visual force page has to display all the Contacts available for an Account .Contacts should be listed out in the table row wise(default being column wise) . Only created "date"(Strip the time part) of the contact should be displayed .

Sample page:

Apex Code :

public class displayContacts<br /> { <br /> <br /> <br /> //Get the respective Account id<br /> ID accountId;<br /> <br /> //Store the wrapped Contacts<br /> public List<contactWrapper> conWrapper{get;set;}<br /> <br /> //COnstructor <br /> public displayContacts()<br /> { <br /> accountId= string.escapeSingleQuotes(ApexPages.currentPage().getParameters().get('id')); <br /> <br /> //Initialize list<br /> conWrapper = new List<contactWrapper>();<br /> for(Contact tempCon :[select FirstName,LastNAme,Email,phone,createddate from contact where accountid=:accountid])<br /> { <br /> //create the object for the wrapper class<br /> contactWrapper tempWrapper = new contactWrapper(tempCon);<br /> conwrapper.add(tempWrapper);<br /> }<br /> <br /> <br /> <br /> } //End of Constructor<br /> <br /> //Wrapper class for Contact<br /> public class contactWrapper<br /> { <br /> public String contactName{get;set;}<br /> public String createdDate{get;set;}<br /> public string phoneC{get;set;}<br /> public string emailC{get;set;}<br /> <br /> public contactWrapper(Contact con)<br /> {<br /> contactName=con.FirstName+' '+con.LastName;<br /> createdDate=con.createddate.month() +'/'+ con.createddate.day() +'/'+ con.createddate.year();<br /> phoneC=con.phone;<br /> emailC=con.email;<br /> <br /> }//End of Wrapper constructor<br /> <br /> }//End of wrapper class <br /> <br /> } //End of Class

Visual force page :
<br /> <apex:page controller="displayContacts"><br /> <apex:pageBlock><br /> <apex:pageBlockSection title="Contacts Available"><br /> <apex:dataTable value="{!conWrapper}" var="item1" border="1" columnsWidth="65px,100px" rowClasses="odd,even" styleClass="tableClass"><br /> <apex:column width="200px"><br /> <table width="250" border="0"> <tr><td><b>Name :</b></td><td>{!item1.contactName }</td></tr> <tr><td><b>Phone :</b></td><td>{!item1.phonec}</td></tr> <tr><td><b>Email :</b></td><td>{!item1.emailc} </td></tr> <tr><td><b>Created Date :</b></td><td>{!item1.createdDate} </td></tr> </table> </apex:column> <br /> </apex:dataTable><br /> </apex:pageBlockSection><br /> </apex:pageBlock><br /> </apex:page><br />

Result :

Huh!! now please don't catch a bug here that no values are displayed for phone. I admit i missed them..Pretty tired ...accept my apology and take it for granted :) :)

Power of wrapper is seamless .It can be used to process only the records that are selected in vf page.Click on the link for example.

http://wiki.developerforce.com/index.php/Wrapper_Class

Happy Coding!
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