Updating Child Objects based on field of parent

Question

I have a workflow on parent object which creates 3 task. When creating a task the description section is updated with text as 'TestLeader'.

Parent Object has field 'TestLeader'.

A trigger(after insert) on parent which loops through this 3 task if desctiption has text 'TestLeader' then update OwnerId field to 'TestLeader' of Parent.

trigger ParentTrigger on ParentObject__c (after insert,after update) {  

    if(Trigger.isInsert && Trigger.isAfter){
       ParentTriggerController.OnAfterInsert(Trigger.new);

}
public Class ParentTriggerController
{
     public static void onafterInsert(List<ParentObject__c> lstTest){

     List<Task> updateTaskList = new List<Task>();
     List<Task> TaskList = new List<Task>();
     list<ParentObject__c> listtest = new List<ParentObject__c>();

     for(ParentObject__c t: lsttest)
     {
        listtest= [SELECT TestLeader__c,(SELECT Id, OwnerId, Description 
                                          FROM Tasks) 
                                        FROM ParentObject__c
                                         WHERE Id = :t.Id];

     }
     for(ParentObject__c po: listtest)
      {   
        system.debug('Parent Object Id' + po.Id);                                      
        TaskList = [SELECT Id, OwnerId, Description 
                    FROM Task
                    WHERE WhatId = : po.Id];                            

       system.debug('TaskList' + TaskList);

       for(Task task:TaskList)
       {
           system.debug('Task:' +task);
           String taskDescription = task.Description;

           Task updateTask = new Task();
           updateTask.Id = task.Id;

           if(taskDescription.contains('TestLeader'))
           {
               updateTask.OwnerId = po.TestLeader__c;
               updateTaskList.add(updateTask);
           }
       }
     }

        if(!updateTaskList.isEmpty())
        {
            update updateTaskList;
        }
    }
}

I am not able to get the list of task here associated with ParentObject__c. It is giving no records. The task records are created by workflow.

Answer 1

I believe this is due to the Trigger order of operations. Your trigger is on your Parent_object, and I assume your workflow is as well. If you look at the order of execution for triggers, Workflow rules aren;t fired until after 'after context' triggers are executed.

https://www.salesforce.com/us/developer/docs/apexcode/Content/apex_triggers_order_of_execution.htm

So at the time of execution for this trigger, your tasks are not created yet. I think what you really want is to make the trigger on the task object, rather than the Parent_object. When the tasks, are created you can query for the Parent objects, and make your changes accordingly.