Item for TODO?

Item for TODO?

[Nick Roberts]

I would like to see some of the toolbar functionality available to text-only
terminals but do not want to do the work. Such a feature would map a bit like
tmm-menubar does, I guess, but I think it would work more naturally. The
buttons could look a bit like those used by custom.el. However, I do not want
to start a discussion about how it would work, just add an entry in TODO
for the next release, in the hope of finding someone who would like to do
it. 

Is it a generally desirable feature and can I add it to TODO? My angle is
to improve Emacs capability as a debugger on a text-only terminal.

Nick

Re: Item for TODO?

[Stefan Monnier]

> Is it a generally desirable feature and can I add it to TODO?

Go for it.  AFAIK the fact that a feature is only available in some but not
all environments is considered as a "misfeature".  Witness, the fact that
most Emacs features (including mouse support as you obviously know) are
supported under a tty.  There's also been discussions to add support for
tooltips, tho it's not clear exactly what this should look like, but it
could begin with a command to "show tooltip at point" which could be added
to the C-h map.


        Stefan

Re: Item for TODO?

[John Paul Wallington]

> There's also been discussions to add support for tooltips, tho it's
> not clear exactly what this should look like, but it could begin
> with a command to "show tooltip at point" which could be added to
> the C-h map.

We have that:

C-h . runs the command display-local-help
   which is an interactive compiled Lisp function in `help-at-pt'.
[...]
Display local help in the echo area.
This displays a short help message, namely the string produced by
the `kbd-help' property at point.  If `kbd-help' does not produce
a string, but the `help-echo' property does, then that string is
printed instead.

Re: Item for TODO?

[Eli Zaretskii]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Fri, 21 Jan 2005 10:55:27 -0500
> Cc: emacs-devel@gnu.org
> 
> There's also been discussions to add support for tooltips, tho it's
> not clear exactly what this should look like

Emacs already has the machinery to support this: if show-help-function
is nil (and it usually is on a tty), the tooltip text is shown in the
echo area.  The Windows port used that functionality before tooltip
support was added to it, and the MS-DOS port still uses it.

So the only thing that's missing is to make the tty mouse support
package inject help-echo events into the Emacs keyboard queue.
Everything else should ``just work''.

Re: Item for TODO?

[Nick Roberts]

 > > There's also been discussions to add support for tooltips, tho it's
 > > not clear exactly what this should look like
 > 
 > Emacs already has the machinery to support this: if show-help-function
 > is nil (and it usually is on a tty), the tooltip text is shown in the
 > echo area.  The Windows port used that functionality before tooltip
 > support was added to it, and the MS-DOS port still uses it.
 > 
 > So the only thing that's missing is to make the tty mouse support
 > package inject help-echo events into the Emacs keyboard queue.
 > Everything else should ``just work''.

What is a help-echo event? 

On an xterm, if you move the mouse around no input characters are generated
for Emacs to read. It only knows where the mouse is when you click a
button. In between, I don't think it knows where the mouse is. How could
it then display a tooltip?

Nick

Re: Item for TODO?

[Eli Zaretskii]

> From: Nick Roberts <nickrob@snap.net.nz>
> Date: Sun, 23 Jan 2005 00:09:39 +1300
> Cc: Stefan Monnier <monnier@iro.umontreal.ca>, emacs-devel@gnu.org
> 
>  > So the only thing that's missing is to make the tty mouse support
>  > package inject help-echo events into the Emacs keyboard queue.
>  > Everything else should ``just work''.
> 
> What is a help-echo event? 

See keyboard.c, functions read_char and show_help_echo.  If the event
found (by kbd_buffer_get_event) in the keyboard queue is a list of the
special form

      (help-echo FRAME HELP WINDOW OBJECT POS)

then Emacs displays the text specified by HELP as a tooltip or an echo
area message (see the comments in keyboard.c immediately before
show_help_echo for the details).

> On an xterm, if you move the mouse around no input characters are generated
> for Emacs to read. It only knows where the mouse is when you click a
> button. In between, I don't think it knows where the mouse is.

Does this mean that the track-mouse form does not work with xt-mouse?

> How could it then display a tooltip?

If there's no way to produce input with xt-mouse, then I think
tooltips cannot be triggered by mouse movements.  You need to come up
with some other method of triggering the tooltip display.  Once you do
come up with such a method, all you need to do is make that method
produce events of the above form, and the rest will work
automagically.

Re: Item for TODO?

[David Kastrup]

"Eli Zaretskii" <eliz@gnu.org> writes:

> If there's no way to produce input with xt-mouse, then I think
> tooltips cannot be triggered by mouse movements.  You need to come
> up with some other method of triggering the tooltip display.  Once
> you do come up with such a method, all you need to do is make that
> method produce events of the above form, and the rest will work
> automagically.

zone could let some ASCII creature meander around the screen,
triggering tooltips when running across them.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum

Re: Item for TODO?

[Richard Stallman]

    I would like to see some of the toolbar functionality available to text-only
    terminals but do not want to do the work.

    Is it a generally desirable feature and can I add it to TODO? My angle is
    to improve Emacs capability as a debugger on a text-only terminal.

I don't see the point.  People who use text-only terminals normally
do so because they prefer text commands.

There is no way to display images, so a "tool bar" would have to have
textual names, and then they might as well be in the menu bar.  (A
menu bar item doesn't have to lead to a menu.  It can execute a
command directly.  Using submenus is just the usual practice.)

Either way, you would have to invoke them with keys.  So why not just
bind the keys instead?

Re: Item for TODO?

[Nick Roberts]

 >     I would like to see some of the toolbar functionality available to
 >     text-only terminals but do not want to do the work.
 > 
 >     Is it a generally desirable feature and can I add it to TODO? My angle is
 >     to improve Emacs capability as a debugger on a text-only terminal.
 > 
 > I don't see the point.  People who use text-only terminals normally
 > do so because they prefer text commands.

Sometimes its because filtering prevents using X (remote connections), sometimes
its more convenient/quicker not to start an X server for simple tasks and
presumably some architectures don't have systems that support X.

 > There is no way to display images, so a "tool bar" would have to have
 > textual names, and then they might as well be in the menu bar.  (A
 > menu bar item doesn't have to lead to a menu.  It can execute a
 > command directly.  Using submenus is just the usual practice.)

Can you give an example of how this would work on a tty?

I can configure a menu-item as a button in X, but if I do the same on a tty
it just presents me with a list of completions (of top-level menu items).

 > Either way, you would have to invoke them with keys.

Thats not true. Text-only does not mean "no mouse". The command
tmm-menubar-mouse can be invoked by clicking on on the menubar with the mouse.

 >  So why not just bind the keys instead?

Since the mouse is generally available on ttys, why should the user be denied
the opportunity to use it?

Nick

Re: Item for TODO?

[Richard Stallman]

    I can configure a menu-item as a button in X, but if I do the same on a tty
    it just presents me with a list of completions (of top-level menu items).
    ...
    Thats not true. Text-only does not mean "no mouse". The command
    tmm-menubar-mouse can be invoked by clicking on on the menubar with the mouse.

If mouse selection doesn't work right for a menu bar item that has no
menu, then it's a bug.  Fixing it should be much easier than adding a
separate tool bar.  Also, since it is a bug fix, it is ok to do it
now.

I still don't think that a tool bar would have any advantage
over the menu bar, for a tty.

Re: Item for TODO?

[Nick Roberts]

 > If mouse selection doesn't work right for a menu bar item that has no
 > menu, then it's a bug.  Fixing it should be much easier than adding a
 > separate tool bar.  Also, since it is a bug fix, it is ok to do it
 > now.
 > 
 > I still don't think that a tool bar would have any advantage
 > over the menu bar, for a tty.

Even if the menu bar is fixed, it seems inconvenient to make tool bar like
buttons share the menu bar with menus. I think its cleaner to keep them
separate and then they can be toggled independently with tool-bar-mode and
menu-bar-mode.

But if you don't think there is any benefit, I'll remove the entry from TODO.


Nick

Re: Item for TODO?

[Richard Stallman]

    Even if the menu bar is fixed, it seems inconvenient to make tool bar like
    buttons share the menu bar with menus. I think its cleaner to keep them
    separate and then they can be toggled independently with tool-bar-mode and
    menu-bar-mode.

It would be useful to make the usual tool-bar definitions work,
although the tty implementation would look basically like the menubar.

Re: Item for TODO?

[David Kastrup]

Richard Stallman <rms@gnu.org> writes:

>     I can configure a menu-item as a button in X, but if I do the
>     same on a tty it just presents me with a list of completions (of
>     top-level menu items).  ...  Thats not true. Text-only does not
>     mean "no mouse". The command tmm-menubar-mouse can be invoked by
>     clicking on on the menubar with the mouse.
>
> If mouse selection doesn't work right for a menu bar item that has
> no menu, then it's a bug.  Fixing it should be much easier than
> adding a separate tool bar.  Also, since it is a bug fix, it is ok
> to do it now.
>
> I still don't think that a tool bar would have any advantage over
> the menu bar, for a tty.

The difference between a toolbar and a menu is that the toolbar
contains immediate actions, only the most important ones.  The screen
real estate on a tty is limited: our current implementation of
keyboard menus is not really convenient for use with a mouse, but can
be configured to take away no space when not used.  Implementing a
toolbar would at least require short button names: I don't think that
we have them available in general.  Maybe one would need mouse-over
action that changes a button [Pre] to [Preview] or similar.
mouse-over action would also make possible having a menu just appear
when the mouse cursor is in the top tty row.

Anyway, there are a number of things that might be worth thinking
about, in particular in connection with mouse-over (and don't forget
that at the time frames we are talking of, we also might negotiate
mouse-over events with gpm and xterm people).

But that discussion is something for after the release, at best.  I
think it would take even too much time to agree on something
definitive for the TODO file.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum