One of the common use cases I experienced developing customization in Salesforce is the ability for end user to selected multiple records from a list and process them. In Salesforce you can do this via client-side scripting using JavaScript. However, it is slow and you don't really have full control of the selected records specially when your doing multi-paging list.
The best approach I believed on doing this is to create an Apex wrapper class. The wrapper class is a class that will represent data for your table with additional properties. An example of using wrapper class is when you want to display an accounts and then select them using a checkboxes. Let's see how we approach that below.
We first create a wrapper class similar to this:
public class AccountWrapperCls { public Boolean isSelected {get;set;} public Account cAccount {get;set;} public AccountWrapperCls(Account cAccount){ this.cAccount = cAccount; } }
As you can see above, the class contains an account and a boolean property. The isSelected property will be referenced by our Visualforce page and will be rendered as a checkbox. To use this wrapper class we need to create a Visualforce controller for our page that will use the class above.
public class MyAccountListCntrlr { // PROPERTIES public List<AccountWrapperCls> acctList {get;set;} public Set<String> selAccountNames {get;set;} public Boolean hasSelAcct {get;set;} // CONSTRUCTOR public MyAccountListCntrlr(){ acctList = new List<AccountWrapperCls>(); selAccountNames = new Set<String>(); for(Account a : [SELECT AccountNumber, Name FROM Account WHERE AccountNumber != NULL LIMIT 5]){ acctList.add(new AccountWrapperCls(a)); } } // METHODS public void displaySelectedAccountNumbers(){ selAccountNames.clear(); hasSelAcct = false; for(AccountWrapperCls cWrapper : acctList){ if(cWrapper.isSelected){ hasSelAcct = true; selAccountNames.add(cWrapper.cAccount. AccountNumber); } } } }
As you can see above, we created a list of type AccountWrapperCls which represents the account record and the additional isSelected property. Please note that we add a method called displaySelectedAccountNumbers() which gets all the account records whose isSelected value is set to TRUE. It also adds those selected account's account number to a set variable we defined in our class which we will use to display account numbers on the page.
Below is our Visualforce page:
<apex:page controller="MyAccountListCntrlr" tabStyle="Account"> <apex:form > <apex:pageBlock title="Account List"> <apex:pageBlockButtons > <apex:commandButton value="Show Selected Accounts" action="{!displaySelectedAccountNumbers}"/> </apex:pageBlockButtons> <!-- ACCOUNT LIST --> <apex:pageBlockTable value="{!acctList}" var="acctWrapper"> <apex:column > <apex:inputCheckbox value="{!acctWrapper.isSelected}"/> </apex:column> <apex:column value="{!acctWrapper.cAccount.AccountNumber}"/> <apex:column value="{!acctWrapper.cAccount.Name}"/> </apex:pageBlockTable> <!-- SELECTED ACCOUNT INFO --> <apex:pageBlockSection > <apex:outputPanel layout="block" rendered="{!hasSelAcct}"> <apex:outputText value="Below are the selected account:"/> <br/> <apex:outputText value="{!selAccountNames}"/> </apex:outputPanel> <apex:outputPanel layout="block" rendered="{!NOT(hasSelAcct)}"> <br/> <apex:outputText value="No account selected."/> </apex:outputPanel> </apex:pageBlockSection> </apex:pageBlock> </apex:form> </apex:page>
Note that we referenced our list variable while using the properties of our wrapper class in the controller .
