Re: Binding mouse key sequences

[Michael Heerdegen <michael_heerdegen@web.de>]

greenwaters <regularclockwork@gmail.com> writes:

> Thank you for answering Michael. 
> I'll try to answer your questions adding some new facts.

Thanks.

I can reproduce everything you say, in all Emacs versions I tried, trunk
is among them.  And indeed it contradicts the manual, which says that
"You can put more than one mouse button in a key sequence".

Can you please make a bug report (M-x report-emacs-bug)?  Please give a
minimal example starting from emacs -Q, and please include the
information that this also happens in trunk.

BTW, I tried hard to find a workaround to make possible what you want,
but failed.  Reading key sequences generally seems to terminate after
any mouse event (try `read-key-sequence'!).

The only thing you can do is to bind mouse-8 to a command (a keymap does
not work) that reads another event and DTRT.


Regards,

Michael.

> 1. Yes, it happens with emacs -Q.
>
> 2. After calling emacs -Q, C-h k mouse-8 gives
>
>  <mouse-8> (translated from <down-mouse-8> <mouse-8>) at that spot is
> undefined
>
> Similar behaviour for C-h k mouse-9.
> After binding with 
>
> (global-set-key   [mouse-8 mouse-9] 'write-file)
>
> C-h k mouse-8 gives
>
> byte-code: Empty menu
>
> 3. However, after binding with
>
> (global-set-key   [mouse-8] 'write-file)
>
> C-h k mouse-8 gives the usual info 
>
> <mouse-8> (translated from <down-mouse-8> <mouse-8>) at that spot runs
> the command write-file, which is an interactive compiled Lisp
> function.
>
> It is bound to <mouse-8>, C-x C-w, <menu-bar> <file> <write-file>.
>
> etc.
>
> and mouse-8 pops up the file selector window.
>
> 4. Now, setting 
>
>  (global-set-key [mouse-8 mouse-9] 'write-file) 
>
> and executing
>
> (progn
>     (push 'mouse-9 unread-command-events)
>     (push 'mouse-8 unread-command-events))
>
> does indeed call write-file.
>
> 5. I used xev to catch mouse key press events in Xorg: both mouse-8 and
> mouse-9 are recognized. This does not tell me much, however, because the
> test used xev's own window. When I tell xev to monitor any other window,
> e.g., emacs, mouse clicks are not catched by xev. 
>
> 6. Setting the debug variable to true gives simply 
>
> Debugger entered--Lisp error: (error "Empty menu")
>
> I replicated the tests above using mouse-3 instead of mouse-8 and mouse-2
> instead of mouse-9. Therefore I doubt there's any relation with high
> numbered mouse buttons in Xorg.
>
> This is all I was able to find out, with one addition: double-mouse-8 or
> drag-mouse-8 always pops up a menu with just two entries, "tool bar" and
> "Menu bar", both giving access to submenus. The former has entries for all
> the buttons in the emacs tool bar, but all entries seem disabled. The latter
> equals the Lisp-Interaction menu (I am performing tests inside the scratch
> buffer). Same using mouse-3 and mouse-2, or using S-mouse-3 and mouse-2;
> therefore it looks definitely as an effect of using global-set-key, and not
> some predefined undocumented behavior. Moreover, globally unsetting
> double-mouse-8 leaves that menu still functional.
>
> BTW I am using 
>
> GNU Emacs 23.4.1 (i486-pc-linux-gnu, GTK+ Version 2.24.10)
> GNU Emacs 23.4.1 (x86_64-pc-linux-gnu, GTK+ Version 2.24.10)
>
> on Debian Wheezy.
>
> Any further hint is welcomed.