Private WithEvents _mdiClient As MdiClient
 
    Private Sub FrmMdi_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        FindMdiClient()
    End Sub
 
    Private Sub FindMdiClient()
        For Each c As Control In Me.Controls
            If TypeOf c Is MdiClient Then
                _mdiClient = CType(c, MdiClient)
                Return
            End If
        Next
    End Sub
 
    Private Sub _mdiClient_Paint(ByVal sender As Object, ByVal e As _
      PaintEventArgs) Handles _mdiClient.Paint
        Debug.WriteLine("paint")
        Dim p As New Pen(Color.Lime, 12)
        e.Graphics.DrawLine(p, 0, 0, 200, 300)
    End Sub