Error: Compile Error: Variable does not exist: Latest_Act_Recent_Comments at line 36 column 71

Question

public class ActivityUpdate {

    public static void updateComments(List<Task> tasklst)
{
     set<ID> Appid = new set<ID>();
    Map<ID,Application__c> MapContact = new Map<ID,Application__c>();
    List<Application__c> contoUpdate = new List<Application__c>();
    List<Application__c> con = new List<Application__c>();
      for(Task tt:tasklst)
      {

    if(tt.WhatId!=NULL){

    Appid.add(tt.WhatId);   
    } 
         Appid.add(tt.WhatId);
        if(!Appid.isEmpty())
        {
        con = [SELECT id,Latest_Act_Recent_Comments__c from Application__c where id IN :Appid]; 

        }
        if(!con.isEmpty())
        {
            for(Application__c c:con)
            {
            MapContact.put(c.id,c); 

            }
        }
        if(!MapContact.isEmpty())
        {
            for(Task t:tasklst)
            {
            if(MapContact.containskey(t.WhatId))
            {
            MapContact.get(t.WhatId).Latest_Act_Recent_Comments__c= t.Latest_Act_Recent_Comments;
            contoUpdate.add(MapContact.get(t.WhatId));
            }   
            }
        }
        if(!contoUpdate.isEmpty())
        {
            update contoUpdate;
        }
    }
 }
 }

Answer 1

t.Latest_Act_Recent_Comments should be t.Latest_Act_Recent_Comments__c at line 36 as it seems like field on Task object. if it is not created create that as per your logic.

Answer 2

Custom fields are supposed to terminate using __c, so as it seems that Latest_Act_Recent_Comments is a custom field you need to use Latest_Act_Recent_Comments__c .