Hello All,
 I’m having some trouble wrapping my head around wrapper classes (pun intended). The basics of what I’m trying to accomplish is to create a map where the key is a concatenation of two strings and the value is a wrapper list that holds multiple primitives. I have done some reading but can’t seem to get it working. The error I’m getting is line 30 “Method does not exist or incorrect signature: [List<OfficerStats_CampaignUpdate.CampAggWrperBooked>].add(String, Date, Integer, Integer, Integer)”. Can someone please help me understand what I’m doing wrong.
 

public class OfficerStats_CampaignUpdate {
    
    public list <Campaign> triggerVarNew;
    public list <Campaign> triggerVarOld;
    
	// Main Class Constructor    
    public OfficerStats_CampaignUpdate (list<Campaign> triggerContNew, list<Campaign> triggerContOld){
        triggerVarNew = triggerContNew;
        triggerVarOld = triggerContOld;
        
		// Get list of effected dates and add to set (from new and old trigger records)
        set<date> EffectedDates = new set<date>();    
        for(Campaign TriggValNew : TriggerVarNew){EffectedDates.add(Date.valueof(TriggValNew.End_Date_Time__c));}
        for(Campaign TriggValOld : TriggerVarOld){EffectedDates.add(Date.valueof(TriggValOld.End_Date_Time__c));}
        
        // get agg result list of campaings within specific dates
        list <aggregateResult> CampaignAggResult = ([SELECT Count(id) countid, sum(New_Memberships__c) Memberships, DAY_ONLY(End_Date_time__c) EventDate, sum(referral_total__c) Referrals, Booked_by__c BookedBy, GROUPING(Booked_By__c) GRPBooked  
                                                     FROM Campaign
                                                     WHERE Status = 'Completed'
                                                     AND DAY_ONLY(End_Date_Time__c) in : EffectedDates
                                                     GROUP BY CUBE (Booked_By__c, DAY_ONLY(End_Date_time__c))
                                                     ORDER BY GROUPING (Booked_by__c)]);
        
		// For each agg result line, check to see if bookedby is null, if not null add to list, then add list to    map value   
        map <string,CampAggWrperBooked> WrapperMap = new map <string,CampAggWrperBooked>();
        
        for (AggregateResult ar : CampaignAggResult){
            if(ar.get('BookedBy') != null){
            	list <CampAggWrperBooked> BookedWrapperList =  new list <CampAggWrperBooked>();
                    BookedWrapperList.add(string.valueof(ar.get('bookedBy')), date.valueof(ar.get('EventDate')), integer.valueof(ar.get('Memberships')), integer.valueof(ar.get('Referrals')), integer.valueof(ar.get('countid')));
                
            }
            
        }
        
    }
      
	// Wrapper Class
    public class CampAggWrperBooked {
        public string BookedBy;
        public date EndDate;
        Public integer SumOfMembers;
        public integer SumOfReferrals;
        Public integer EventCount;
		// Wrapper Constructor            
        public CampAggWrperBooked(string BookedByWrap, date EndDateWrap, integer SumOfMembersWrap, integer SumOfReferralsWrap, integer EventCountWrap){
            this.BookedBy = BookedByWrap;
            this.EndDate = EndDateWrap;
            this.SumOfMembers = SumOfMembersWrap;
            this.SumOfReferrals = SumOfReferralsWrap;
            this.EventCount = EventCountWrap;
        }            
    }   
}