Hi there everyone,

I have a requirement to build a report that has sub totals and grand totals in it. Since I can't seem to figure out how to do this in the Salesforce reporting functionality, I'm doing it with a Visual force form. My thought was that I would process through a Object and group the entries by 'Activity'. When the activity changed, I would do a 'Sub total' for the activity. My thinking was that i would take the rows out of the 'SourceEntries' list, and add them to the 'TimeEntrires' list. When the Activity changes, then I would add an extra row to the list that serves as a 'Subtotal' like. Though I have some of the psuedo code in there and commented out, I'm finding that I can't even take information from one list to another.

Can anyone guide me on what I might be doing wrong. I am getting 'Attempt to de-reference a null object'.
The problem is with the statement 'TimeEntries.add(a);
The value of the debug statement is: DEBUG|Time_Entry__c:{Id=a04r0000002303wAAA, Activity__c=Research, Date_Worked__c=2017-04-14 00:00:00, Hours_Worked__c=1, Minutes_Worked__c=00, Work_Description__c=This is the first v1.2 time entry record for create time entry.}

The code involved is the following:

public class TERepController {

    //This is the list for handling the group of time entries related to the parent object. 
    public list<Time_Entry__c> SourceEntries {get;set;}
    //This is the list that will handle the detail with the totals added too it. 
    public List<Time_Entry__c> TimeEntries;

    //Used to get the parent request object ID from the Visual force page to the controller. 
    public string ReqID {get;set;}
    
    //Used to identify when there is an activity change for total generation. 
    public string strOldActivity = 'None';
    
    //Used to detect if a Row entered without selecting an action. 
    public TERepController(ApexPages.StandardController controller) 
    {
        //Obtain the parent object Id from the the visualforce form. 
        ReqId = Apexpages.currentPage().getparameters().get('Id');
        //Call the loaddata method to laod the time entries related to the parent object. 
        LoadData();
     }
    public void LoadData()
    {
        //Obtain the first 15 bytes of the Parent Object ID to use for record selection. 
        ReqId = 'a03r0000000rwC0';
        string RequestID = ReqId.substring(0, 15);
        //Load the related time entry records from the database. 
        SourceEntries = [select id, Activity__c, Date_Worked__c, Hours_Worked__c, Minutes_Worked__c, Work_Description__c from Time_Entry__c WHERE Related_Object__c=:RequestID order by Activity__c, ID]; 
        for(Time_Entry__c a : SourceEntries)
        {
//            if(a.Activity__c == strOldActivity)
//            {
//            	TimeEntries.add(new SourceEntries(a));
//            }
//            	else if(strOldActivity == 'None')
//                    {
                        System.debug(a);
             			TimeEntries.add(a);
//                        strOldActivity = a.Activity__c;
//                    }
//                    	else
//                        {
//                            Time_Entry__c b = new Time_Entry__c(Activity__c=strOldActivity, Work_Description__c='Activity Total', Hours_Worked__c='8', Minutes_Worked__c='30');
//                            TimeEntries.add(new SourceEntries(b));
//             				TimeEntries.add(new SourceEntries(a));
//                        	strOldActivity = a.Activity__c;
//                        }
        } 
        insert TimeEntries;
        return;
    }

}

I'd welcome any assistance anyone can provide me.

Thanks!

Eric Anderson