function readOnly(count){ }
Sign Up ›
Starting November 20, the site will be set to read-only. On December 4, 2023,
forum discussions will move to the Trailblazer Community.
Learn More

Browse by Topic
ShowAll Questionssorted byDate Posted
+ Start a Discussion
venkat bojjavenkat bojja 

Execution of AfterUpdate caused by: System.FinalException: Record is read-only

Hi Team ,
I have wrote a trigger. When ever the record is updated I need update the pick list field which is Car_Type__c. But I'm gettng below error. Please let me know the why the error message is getting and solution for it.

Error Message :   execution of AfterUpdate caused by: System.FinalException: Record is read-only

Triggger :

trigger DiscountonCarprice on V_Customers__c (after insert,after update) {
    if(Trigger.isInsert && Trigger.isAfter ){
       DiscountonCarpriceController.Discount(trigger.new); 
    }
    else if(Trigger.isupdate && Trigger.isAfter ){
        system.debug('Im in else block');
      DiscountonCarpriceController.DiscountAfterUpdate(trigger.new,trigger.oldmap);   
    }
}

=================================
Apex Class :

public class DiscountonCarpriceController {
    Public static void discount(list<V_Customers__c> vclist){
        set<id> vcId = new set<id>();
         list<V_Customers__c> updateVc = new list<V_Customers__c>();
        for(V_Customers__c vcCust:vclist){
            vcId.add(vcCust.id);
            
        }
        list<V_Customers__c> updateVcList = [select id,name,Country__c,Discount__c from V_Customers__c where id =: vcId];
        for(V_Customers__c vc: updateVcList){
            if(vc.Country__c=='INDIA'){
                vc.Discount__c = 20;
                //updateVc.add(vc);
            }
                else if(vc.Country__c=='UK'){
                vc.Discount__c = 15;
                  //  updateVc.add(vc);
            }
                else if(vc.Country__c=='USA'){
                vc.Discount__c = 10;
                   // updateVc.add(vc);
            }
            
        }
        update updateVcList;
    }
    Public static void DiscountAfterUpdate(list<V_Customers__c> vclist,map<id,V_Customers__c> vcoldMap){ 
         set<id> vcId = new set<id>();
        for(V_Customers__c vcCust:vclist){
            vcId.add(vcCust.id);
            
        }
        system.debug('vclist****'+vclist);
         system.debug('vcoldMap****'+vcoldMap);
        list<V_Customers__c> vclist1 = new list<V_Customers__c>();
          list<V_Customers__c> vclist2 = [select id,name,Country__c,Discount__c,Car_Type__c from V_Customers__c where Id IN :vcId];
        for(V_Customers__c vc:vclist){
            if(vcoldMap.get(vc.id).id == vc.id ){
                 vc.Car_Type__c = 'Hatchback';
               vclist1.add(vc);
                
                system.debug('Discount Amount***'+ vc.Discount__c);
            } 
            
        }
       
            system.debug('vclist1***'+ vclist1);
            update vclist1;
             system.debug('vclist1***'+ vclist1);
        
        
    }
}

=============================
Error Screenshot:
FYI:
User-added image
Best Answer chosen by venkat bojja
DevidDevid

Do it on before update not on after update.
and if you still want to do it on after update create new list and records on that list and do DML like

Example: 

list<V_Customers__c> vclist1 = new list<V_Customers__c>();
list<V_Customers__c> vclist2 = [select id,name,Country__c,Discount__c,Car_Type__c from V_Customers__c where Id IN :vcId];
for(V_Customers__c vc:vclist){
	if(vcoldMap.get(vc.id).id == vc.id ){
		vclist1.add(new V_Customers__c(Id = vc.Id, Car_Type__c = 'Hatchback'));
		system.debug('Discount Amount***'+ vc.Discount__c);
	}
}
system.debug('vclist1***'+ vclist1);
update vclist1;

All Answers

DevidDevid

Do it on before update not on after update.
and if you still want to do it on after update create new list and records on that list and do DML like

Example: 

list<V_Customers__c> vclist1 = new list<V_Customers__c>();
list<V_Customers__c> vclist2 = [select id,name,Country__c,Discount__c,Car_Type__c from V_Customers__c where Id IN :vcId];
for(V_Customers__c vc:vclist){
	if(vcoldMap.get(vc.id).id == vc.id ){
		vclist1.add(new V_Customers__c(Id = vc.Id, Car_Type__c = 'Hatchback'));
		system.debug('Discount Amount***'+ vc.Discount__c);
	}
}
system.debug('vclist1***'+ vclist1);
update vclist1;
This was selected as the best answer
DevidDevid
Public static void setCarType(list<V_Customers__c> vclist, map<id,V_Customers__c> vcoldMap){
	for(V_Customers__c vc:vclist){
		if(vcoldMap.get(vc.id).Car_Type__c != vc.Car_Type__c ){
			vc.Car_Type__c = 'Hatchback';
		}
	}
}

On before update it should be something like this.