Hi All,

I have trigger on after insert and after update, below is my handler class.

If i create a task from contact(is a required field on page layout) it fails because whatID is null. So I'm trying to query to get the whatID based on whoID.

If i create a task from account, works fine because whoid and whatid are not null.

public with sharing class TaskTriggerHandler {
    
    private boolean trigger_isExecuting = false;
    
    public TaskTriggerHandler(){
        
    }
    
    public void OnAfterInsert(Task[] newObjects){
        // EXECUTE AFTER INSERT LOGIC       updateAccountActivityFields(newObjects);
    }
    
    public void OnAfterUpdate(Task[] oldObjects, Task[] updatedObjects, Map<ID, Task> ObjectMap){
        //EXECUTE AFTER UPDATE LOGIC
        updateAccountActivityFields(updatedObjects);
    }
    

     public void updateAccountActivityFields(Task[] taskRecords){
      
        // find task record type 
        RecordType taskRec = [SELECT Id FROM RecordType WHERE SobjectType ='Task' AND DeveloperName ='Task_Record_Type'];
        
        List<Account> accountsToUpdate = new List<Account>();
        Account a;
       
        //Get all the contactIds and accountIds of the task being inserted/updated
        for(Task tk : [SELECT Id, LastModifiedBy.name, type, LastModifiedDate, CreatedDate, RecordTypeId, whoid, whatid FROM task WHERE id in :taskRecords]){
            if(tk.RecordTypeId == taskRec.Id  && tk.Whoid!=null){
                
                // query to get account ID from contact:whoID 
                a = new Account(Id = [SELECT AccountId FROM Contact  WHERE Id =: tk.WhoId Limit 1].AccountId);
                //convert task's CreatedDate, datetime to date
                Date createdDateJustDate = date.newinstance(tk.CreatedDate.year(), tk.CreatedDate.month(), tk.CreatedDate.day());
        
                //update the activity fields on account with Task's lastModifiedDate and LastModifiedBy based on Task Type
                if(tk.type=='Face 2 Face Meeting' || tk.type=='Lunch'){
                    a.Last_Face_to_Face_Activity__c = createdDateJustDate;
                    a.Last_Visited_By__c = tk.LastModifiedBy.name;
      
                }
                else{
                    a.Last_Call_Activity__c =  createdDateJustDate;
                    
                }
                
                accountsToUpdate.add(a);
               
            }
        }
        
       if(!accountsToUpdate.isEmpty())
            Update accountsToUpdate;

My test Class :

Please help!!
    
    public void OnAfterUpdate(Task[] oldObjects, Task[] updatedObjects, Map<ID, Task> ObjectMap){
        //EXECUTE AFTER UPDATE LOGIC
        System.debug('SAFELITE_DEBUG:TaskTriggerHandler:OnAfterUpdate:: updatedObjects=' + updatedObjects);
        updateAccountActivityFields(updatedObjects);
    }
    

     public void updateAccountActivityFields(Task[] taskRecords){
        /* when a task of RecordType(Safelite_Task_Record_Type) is created/updated either from Account or Contact then 
        update Account fields : Last_Face_to_Face_Activity__c, Last_Visited_By__c & Last_Call_Activity__c based on task type
        */
        System.debug('SAFELITE_DEBUG:TaskTriggerHandler:updateAccountActivityFields:: taskRecords=' + taskRecords);

        // find task record type 
        RecordType taskRec = [SELECT Id FROM RecordType WHERE SobjectType ='Task' AND DeveloperName ='Safelite_Task_Record_Type'];
        System.debug('SAFELITE_DEBUG:TaskTriggerHandler:updateAccountActivityFields:: taskRec.Id=' + taskRec.Id);
        
        List<Account> accountsToUpdate = new List<Account>();
        Account a;
         
        //Map of Account IDs and Accounts
        Map<id,account> accMap = new Map<id,account>();
       
        //Get all the contactIds and accountIds of the task being inserted/updated
        for(Task tk : [SELECT Id, LastModifiedBy.name, type, LastModifiedDate, CreatedDate, RecordTypeId, whoid, whatid FROM task WHERE id in :taskRecords]){
            if(tk.RecordTypeId == taskRec.Id  && tk.Whoid!=null){
                
                a = new Account(Id = [SELECT AccountId FROM Contact  WHERE Id =: tk.WhoId LIMIT 100].AccountId);
                              
                System.debug('SAFELITE_DEBUG:TaskTriggerHandler:updateAccountActivityFields:: tk.WhatId=' + tk.WhatId);
                
                //convert task's CreatedDate, datetime to date
                Date createdDateJustDate = date.newinstance(tk.CreatedDate.year(), tk.CreatedDate.month(), tk.CreatedDate.day());
                System.debug('SAFELITE_DEBUG:TaskTriggerHandler:updateAccountActivityFields:: createdDateJustDate=' + createdDateJustDate);
                
                //update the activity fields on account with Task's lastModifiedDate and LastModifiedBy based on Task Type
                if(tk.type=='Face 2 Face Meeting' || tk.type=='Lunch'){
                    a.Last_Face_to_Face_Activity__c = createdDateJustDate;
                    a.Last_Visited_By__c = tk.LastModifiedBy.name;
                    accountsToUpdate.add(a);
                    System.debug('SAFELITE_DEBUG:TaskTriggerHandler:updateAccountActivityFields:: Last_Face_to_Face_Activity__c=' + a.Last_Face_to_Face_Activity__c);
                    System.debug('SAFELITE_DEBUG:TaskTriggerHandler:updateAccountActivityFields:: Last_Visited_By__c=' + a.Last_Visited_By__c);
                }
                else{
                    a.Last_Call_Activity__c =  createdDateJustDate;
                    accountsToUpdate.add(a);
                    System.debug('SAFELITE_DEBUG:TaskTriggerHandler:updateAccountActivityFields:: Last_Call_Activity__c=' + a.Last_Call_Activity__c);
                }
                //Populate accMap with the Account IDs and Account record
                accMap.put(a.id,a);
               
            }
        }
        
         if(!accMap.isEmpty()){
            Update accMap.values();
        }
            
    }
}

My Test Class:
 static testMethod void testAdminUserwithTask() {
        
        // Next make sure that a System Admin *can* delete an attachment
        Profile adminProf = [select id from profile where name='System Administrator']; 
        User au = new User(alias = 'Admint', email='AdminUser@asdahsdjkhkjashdjasd.com',emailencodingkey='UTF-8',FirstName='Admin',
                           lastname='task',languagelocalekey='en_US',localesidkey='en_US',profileid = adminProf.Id,
                           timezonesidkey='America/Los_Angeles',username='AdminUser@asdahsdjkhkjashdjasd.com');
        // Switch current user to System Admin user
        System.runAs(au) {
            // Create test data (a new Account with an Attachment)
            Account a = new Account(Name='Testtasking');
            insert a;
            Contact con = new Contact(LastName='Test',FirstName='asdasd',Email='asdasd@adsasd.com') ;
            insert con ; 
            List<Task> tasks = new List<Task>{};
                for(Integer i = 0; i < 200; i++) 
            {
                Task t = new Task(Subject='Donni'+i,Status='New',Priority='Normal',Type='Phone Call', whoId =con.Id, whatId = a.Id );
                tasks.add(t);
            }
            test.startTest();
            insert tasks;
            test.stopTest();
            
            try {
                delete tasks;
            } catch (Exception e) {
                
            }
            
        }
    }