bug#24019: 25.1.50; Allow using a custom callback with xwidget

[Stefan Kangas <stefan@marxist.se>]

Hi Joakim,

Puneeth Chaganti <punchagan@muse-amuse.in> writes:

> Hello,
>
> `xwidgets.el' seems to have some commented code that used to allow using
> a different callback on each xwidget.  This functionality is useful to
> have and this is a patch that uncomments this code.  I've tested the
> code, and it seems to work, and I'm not really sure, why this was
> commented in the first place.
>
> Thanks!

Could you please help review the below patches?  They were submitted
to the Emacs bug list in 2016, but no one has followed up on them.

Best regards,
Stefan Kangas

>
>>From 63d1b53583263065edea3ee53d708693415a6057 Mon Sep 17 00:00:00 2001
> From: Puneeth Chaganti <punchagan@muse-amuse.in>
> Date: Mon, 18 Jul 2016 16:34:24 +0530
> Subject: [PATCH 1/2] Use the callback set as widget's property
>
> Revert a commented piece of code, that allows using a different callback
> for each xwidget on an event, instead of a single global one.
> * lisp/xwidget.el (xwidget-event-handler): Use callback widget property
> ---
>  lisp/xwidget.el | 8 ++------
>  1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/lisp/xwidget.el b/lisp/xwidget.el
> index 7a0ca8b..3434e24 100644
> --- a/lisp/xwidget.el
> +++ b/lisp/xwidget.el
> @@ -172,12 +172,8 @@ xwidget-event-handler
>    (let*
>        ((xwidget-event-type (nth 1 last-input-event))
>         (xwidget (nth 2 last-input-event))
> -       ;;(xwidget-callback (xwidget-get xwidget 'callback))
> -       ;;TODO stopped working for some reason
> -       )
> -    ;;(funcall  xwidget-callback xwidget xwidget-event-type)
> -    (message "xw callback %s" xwidget)
> -    (funcall  'xwidget-webkit-callback xwidget xwidget-event-type)))
> +       (xwidget-callback (xwidget-get xwidget 'callback)))
> +    (funcall xwidget-callback xwidget xwidget-event-type)))
>  
>  (defun xwidget-webkit-callback (xwidget xwidget-event-type)
>    "Callback for xwidgets.
> -- 
> 2.7.4
>
>
>>From 095f02a5581c2c5c157ec312a64288b0c675da74 Mon Sep 17 00:00:00 2001
> From: Puneeth Chaganti <punchagan@muse-amuse.in>
> Date: Mon, 18 Jul 2016 17:46:19 +0530
> Subject: [PATCH 2/2] Allow specifying the callback if new session
>
> This change makes it easier to create xwidgets with their callbacks that
> are invoked by the event handler
> * lisp/xwidget.el (xwidget-webkit-new-session): Optional callback arg
> ---
>  lisp/xwidget.el | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/lisp/xwidget.el b/lisp/xwidget.el
> index 3434e24..0f6751e 100644
> --- a/lisp/xwidget.el
> +++ b/lisp/xwidget.el
> @@ -416,16 +416,17 @@ xwidget-webkit-fit-width
>                                   (car (window-inside-pixel-edges)))
>                                1000))
>  
> -(defun xwidget-webkit-new-session (url)
> +(defun xwidget-webkit-new-session (url &optional callback)
>    "Create a new webkit session buffer with URL."
>    (let*
>        ((bufname (generate-new-buffer-name "*xwidget-webkit*"))
> +       (callback (or callback #'xwidget-webkit-callback))
>         xw)
>      (setq xwidget-webkit-last-session-buffer (switch-to-buffer
>                                                (get-buffer-create bufname)))
>      (insert " 'a' adjusts the xwidget size.")
>      (setq xw (xwidget-insert 1 'webkit  bufname 1000 1000))
> -    (xwidget-put xw 'callback 'xwidget-webkit-callback)
> +    (xwidget-put xw 'callback callback)
>      (xwidget-webkit-mode)
>      (xwidget-webkit-goto-uri (xwidget-webkit-last-session) url)))