Michael Welle <mwe012008@gmx.net> writes:

> Hello,
>
> Sharon Kimble <boudiccas@skimble.plus.com> writes:
>
>> How can I have a task which when I change its state from TODO or NEXT to
>> IN-PROGRESS starts clocking it until its state is changed back from
>> IN-PROGRESS to some other state, when the clocking will cease?
>
> you can utilise the org-after-todo-state-change-hook. Something like
> this should do the trick:
>
> (defun foo ()
>   (when (and (string= org-state "IN-PROGRESS")
>              (string= org-last-state "TODO")
> 	     (not (string= org-last-state org-state)))
>     (org-clock-in)))
>
> (add-hook 'org-after-todo-state-change-hook 'foo)
>
> The same mechanism can be used to clock out again.
>

Thanks Michael, it works very well. This is the actual coding that I
used -

--8<---------------cut here---------------start------------->8---
#+begin_src emacs-lisp
(defun org-clockin ()
  (when (and (string= org-state "IN-PROGRESS")
             (string= org-last-state "TODO")
       (not (string= org-last-state org-state)))
    (org-clock-in)))

(add-hook 'org-after-todo-state-change-hook 'org-clockin)
#+end_src

#+begin_src emacs-lisp
(defun org-clockout ()
  (when (and (string= org-state "TODO")
             (string= org-last-state "IN-PROGRESS")
       (not (string= org-last-state org-state)))
    (org-clock-out)))

(add-hook 'org-after-todo-state-change-hook 'org-clockout)
#+end_src
--8<---------------cut here---------------end--------------->8---

Thanks
Sharon.
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