XL 2010 Ajouter dans une Listbox uniquement les infos qui respectes certaine conditions (VBA)

Option Explicit
Dim i As Integer
Dim Lig As Integer
Dim Ligtache As Integer
Dim c As Integer


Private Sub Label5_Click()

End Sub

Sub UserForm_Activate()   'va chercher les projet en cours
   
    For i = 8 To 1000
    If Projet.ListIndex = -1 And Range("A" & i) <> "" Then _
        Projet.AddItem Sheets("Feuil1").Range("A" & i).Value
    Next
    If choix_Boite.ListIndex = -1 Then _
    choix_Boite.List = WorksheetFunction.Transpose(ActiveSheet.Range("G7:H7"))
   
    If Spe.ListIndex = -1 Then _
        Spe.Clear
        Spe.AddItem "Soudage"
End Sub

Private Sub Projet_Change()   'va chercher les diferente taches du projet selectionné
    If Projet.ListIndex = -1 Then _
        Me.TacheZone.Clear
   
        With Sheets("Feuil1")
            Lig = .Columns(1).Cells.Find(Me.Projet.List(Me.Projet.ListIndex)).Row
            Me.TacheZone.Clear
            For i = Lig + 1 To Range("B" & Lig + 1).End(xlDown).Row
                Me.TacheZone.AddItem Sheets("Feuil1").Range("B" & i).Value
            Next
        End With
    Exit Sub
End Sub

Private Sub Spe_Change()   'pas utile dand l'example
    If Spe.Value = "Soudage" Then
        Me.Label4.Visible = True
        Me.choix_Boite.Visible = True
        Me.Label5.Visible = True
        Me.List_Ouvr.Visible = True
        Label5.Caption = "Soudeurs :"
        Me.List_Ouvr.Clear
    End If
End Sub

Private Sub choix_Boite_Change()   'va chercher la liste des ouvriers en foction de la boite et la transpose dans la Listbox
    If choix_Boite.Value = "Boite 1" Then   'code que je veux modifier
        Me.List_Ouvr.Clear
        List_Ouvr.List = WorksheetFunction.Transpose(ActiveSheet.Range("I7:T7"))
       
'_____________________Partie du code que je n'arrive pas a ecrire __________________________________
'        For i = 8 To 21
'        Ligtache = Columns(2).Cells.Find(Me.TacheZone.List(Me.TacheZone.ListIndex)).Row
'          
'         If Range("C" & i) >= Range("C" & Ltache) Or Range("E" & i) <= ("E" & Ltache) Then
'                For c = 9 To 20
'                    If Cells(c, i) = "" Then
'                        List_Ouvr.List = WorksheetFunction.Transpose(ActiveSheet.Cells(c, 7))
'                    End If
'                Next
'            End If
'        Next
'__________________________________________________________________________________________________
    End If


    If choix_Boite.Value = "Boite 2" Then   'code sans filtrer les ouvriers occupés
        Me.List_Ouvr.Clear
        List_Ouvr.List = WorksheetFunction.Transpose(ActiveSheet.Range("U7:AP7"))
    End If
End Sub