logic behind or use of label->style->"gtk-label-wrap-width"->width, was: Re: configure-event on eventbox in composite widget

["Karl H. Beckers" <karl h beckers gmx net>]

Hi Matthias, Owen, et. al.

[...]

> > I was a little too enthusiastic, perhaps ... now I've shot myself in the 
> > foot.
> >
> > I have this hbox with a callback connected to size-allocate which (among 
> > other things) changes the text in a label contained in the hbox. This 
> > apparently generates another size-allocate event on the hbox ... a loop.
> hat sounds very wrong. Whatever you are trying to achieve, connecting
> to size-allocate is most likely not the right way to achieve it.
>  
of course you're right, I might have explained what it is, I want to 
achieve earlier.
I'm trying to get a label auto-line-wrap in a nice way when it is resized.

btw. I solved the previous problem by filtering any size-allocate events 
that don't actually
change the widget's width (that was just an oversight on my side). This 
approach works
considerably well.

However:
- the wrap width is NOT the size of the lable (which one could naively 
understand from the
   API docs)
- re-setting the text in a lable doesn't necessarily recalculate the 
wrap_width

... in the sources I found a style property "gtk-label-wrap-width", but 
I don't quite understand
it:

- Setting "gtk-label-wrap-width"->width = widget-width * 1000 seems to 
make the text wrap
   at roughly the widget's size ?!? *blink*
-  Also, let's say I initially have 3 lines where I have manually 
inserted one newline character.
   If I make the label narrower, the line wrap will add lines. If I 
make the the widget wider, the
   second line will get longer (the first is manually terminated), 
until some sort of maximum
   is reached. Then the second line will get shorter again, and the 
number of lines will never
   drop down to 2, no matter how wide I make the widget. I can see that 
the label does some
   guessing of desired width's to beautify the output,
   Do I read the following correctly, that the maximum wrap_width is 1/ 
2 the screen width?
   (this is 2.4 
http://cvs.gnome.org/viewcvs/gtk%2B/gtk/gtklabel.c?rev=1.150&view=markup)

1482               width = MIN (width,
1483                            PANGO_SCALE * (gdk_screen_get_width 
(screen) + 1) / 2);

- If I do a gtk_widget_set_size_request on the label, I can't get the 
"gtk-label-wrap-width"
   style property anymore?!?

TIA,

Karl.