On 9/2/21 6:38 PM, Bill Spitzak wrote:

It does seem like a bug, calling value() should not have any side-effects. Especially because the tabs widget works even if nobody calls value().

    Ah, it is weird that just testing with Fl_Tabs::value(void) can apparently
    end up calling hide() and show().. yikes.

    That code goes back to 1999 though, so looks like you'd know for sure:

49a0693962 (Matthias Melcher   2006-08-17 13:43:07 +0000 308) Fl_Widget* Fl_Tabs::value() {
a7904da09a (Bill Spitzak       1999-10-15 09:01:48 +0000 309)   Fl_Widget* v = 0;
a7904da09a (Bill Spitzak       1999-10-15 09:01:48 +0000 310)   Fl_Widget*const* a = array();
a7904da09a (Bill Spitzak       1999-10-15 09:01:48 +0000 311)   for (int i=children(); i--;) {
a7904da09a (Bill Spitzak       1999-10-15 09:01:48 +0000 312)     Fl_Widget* o = *a++;
a7904da09a (Bill Spitzak       1999-10-15 09:01:48 +0000 313)     if (v) o->hide();
a7904da09a (Bill Spitzak       1999-10-15 09:01:48 +0000 314)     else if (o->visible()) v = o;
a7904da09a (Bill Spitzak       1999-10-15 09:01:48 +0000 315)     else if (!i) {o->show(); v = o;}
f9039b2ae2 (Michael R Sweet    1998-10-06 18:21:25 +0000 316)   }
f9039b2ae2 (Michael R Sweet    1998-10-06 18:21:25 +0000 317)   return v;
f9039b2ae2 (Michael R Sweet    1998-10-06 18:21:25 +0000 318) }

    Perhaps that's the cause, because that last line in the loop that
    calls o->show() on the last item seems to be maybe what's forcing
    the last child to be visible if no other one is..