How to execute a line-drawing subroutine/macro?

Hi!

Thanks a lot for this. However, my computer is flagging it with some message saying that it doesn't trust the file. Just to be on the safe side, could you tell me the code you used? I hate to be so skeptical, but I also want to work on my VBA coding skills.

Also, I've been working on it myself, and I got the line drawing part to work by calling the subroutine in another macro. I want to get it to draw arrows instead of lines and take the selected cells as a range.

Sub Connect(r1 As Range, r2 As Range)
    ActiveSheet.Shapes.AddLine r1.Left + r1.Width / 2, r1.Top + r1.Height / 2, _
    r2.Left + r2.Width / 2, r2.Top + r2.Height / 2
End Sub

Sub Macro4()
'
' Macro4 Macro
'

'
    Connect Range("A3"), Range("D7")
End Sub

Thanks!