Re: scrollbar (again)

[Luc Teirlinck]

Kai GrossJohann wrote:
   
   IIRC, the behavior in the no-toolkit case is similar to xterm.  That
   is, the top of the thumb will be warped to where you clicked mouse-2.

   I agree that this makes it difficult to start dragging.  It's
   something I don't like about this kind of scrollbar.  Nevertheless, I
   think it's still the best scrollbar there is, functionality-wise.

For the no-toolkit scrollbar the *top* of the slider (thumb, whatever)
moves to where you click with mouse-2.  In the case of the Xaw3d
scrollbar the *middle* moves to where you click.  So if you want to
use the scrollbar with mouse-2 to drag (without initial scrolling),
you have to grab it by the top for the native one and (more difficult)
exactly in the middle for the Xaw3d one.  (I do not know about the
other varieties of scrollbars.)  This mainly matters in large buffers.

The best solution may indeed be to either only use mouse-2 for
dragging in large buffers if you do not mind about the initial
scrolling or be very careful about where you grab the slider.

In the case of the native scrollbar, the documentation string you get
from C-h k and then clicking mouse-2 on the slider still misleadingly
suggests that scrolling only takes place if you click *outside* the
slider, whereas it happens regardless of where you click (except at the
very top, where the top still winds up where you click, except that it
is already there).  The documentation you get in the same situation
for the Xaw3d scrollbar throws me off completely.

Unless the behavior itself would be changed I suggest to replace, the
current documentation string for `scroll-bar-drag', namely:

"Scroll the window by dragging the scroll bar slider.
If you click outside the slider, the window scrolls to bring the slider there."

By something like:

"Scroll the window to bring the slider to where you click.
You can then subsequently scroll the window by dragging the slider."

If this is intended for general scrollbars, not just the native one,
we can not be more specific and say which part of the slider gets
moved to where you click.  If the user cares, he will just have to try
it out to see.

This would only help the native scrollbar.  The C-h k output for the
Xaw3d case seems strange.

Sincerely,

Luc.