Re: Changes for emacs 28

[Caio Henrique]

Eli Zaretskii <eliz@gnu.org> writes:

>> Date: Fri, 11 Sep 2020 12:15:09 +0200
>> From: Ergus <spacibba@aol.com>
>> Cc: caiohcs0@gmail.com, emacs-devel@gnu.org
>> 
>> I tried it but there is a problem enabling disabling the icon. It
>> doesn't enable automatically when I do an undo until I click with the
>> mouse somewhere.
>> 
>> Maybe it is a redisplay problem?
>
> No, because the Cut and Paste button have no such problems.

I tried that code again and I experienced the same thing as Ergus, but
only in some cases. If I:
1. launch emacs -Q
2. type only the letter "a"
3. click on the "Undo" button on the toolbar

Then the "Redo" button on the toolbar activates and all works well.

But if I try:
1. launch emacs -Q
2. type the letter "a"
3. press RET to insert newline
4. type the letter "b"
5. click on the "Undo" button on the toolbar

In this case the "Redo" toolbar button doesn't activate (but the "Redo"
button on the menu bar works fine). Then if I click with the mouse
anywhere inside the buffer, then the toolbar menu activates.
I don't know what the problem is, any ideas?

> Thanks, but please add a help-echo text for that button.  The menu
> item perhaps could do without it, but not the tool-bar button.

Isn't the help-echo text the one that appears when I place my mouse over
the toolbar button? Isn't this text the same one used for the menu bar
buttons? When I place my mouse over "Redo" on the toolbar, it says "Undo
last undo".