VBA for Task Dependencies

Question

Say a task has two dependency chains associated with it. For instance, suppose one chain goes from task 2 to 4 to 8 to 10 and another chain goes from 2 to 5 to 9. When looping through the task dependencies object recursively, is there some way to detect
when the links shift from one chain to another?
I'm using the approach outlined by Rod Gill on pp 335-6 of his fine book. (See below.) The approach does not seem to differentiate between the two chains--Flag20 is marked for both chains at the same time. I need to process one chain, then the other.
Public Sub DepSucc(Tsk As Task)
Dim Dep As TaskDependency
If Tsk.Flag20 = False Then
    Tsk.Flag20 = True
    For Each Dep In Tsk.TaskDependencies
        If (Dep.To.ID <> Tsk.ID) Then
            DepSucc Dep.To
        End If
    Next
End If
End Sub
RobVV

Answer 1

The first time you loop through all dependencies for the selected task you need to set in a variable what field to update. So you need a wrapper sub around what you have, something like (not tested)
Public Sub DepFirstSucc(Tsk As Task)
Dim Dep As TaskDependency
Dim Flagnum as Long
FlagNum = FlagNum
If Tsk.GetField(FlagNum) = False Then
Tsk.SetField FlagNum, True
For Each Dep In Tsk.TaskDependencies
If (Dep.To.ID <> Tsk.ID) Then
DepSucc Dep.To, FlagNum
FlagNum = FlagNum - 1
End If
Next
End If
End Sub
Public Sub DepSucc(Tsk As Task, FlagNum as Long)
Dim Dep As TaskDependency
FlagNum = FlagNum
If Tsk.GetField(FlagNum) = False Then
Tsk.SetField FlagNum, True
For Each Dep In Tsk.TaskDependencies
If (Dep.To.ID <> Tsk.ID) Then
DepSucc Dep.To, Flagnum
End If
Next
End If
End Sub
Note Flag20 is last flag, so I decrement the Flagnum field to use Flgag19 etc.
Rod Gill
Author of the one and only Project VBA Book
www.project-systems.co.nz