Re: Strange bug while subclassing Gtk2::Box

[Jaap Karssenberg <j g karssenberg student utwente nl>]

muppet wrote:
> Jaap Karssenberg said: 
> > Ok, the problem is not that propagate_expose doesn't work, the problem
> > is that my box object doesn't get expose events in the first place. I
> > tried adding "expose_mask" for my box object but that didn't help. Any
> > other suggestions on what should be turned on/off in order to get expose
> > events ?
>
> SHould you be chaining up in size-allocate or size-request?  Are there any
> signals whose propagation you're inhibiting by accident?
>
> Try adding propagate_expose() in a callback for the toplevel window's
> expose-event.

Ok, I found the solution: chainging up is required in size_allocate. The 
strange part remains the question why. I didn't find size_allocate 
methods in gtkbox or gtkcontainer so which parent closure is actually 
called here?

A clue might be that even if I send propagate_expose() calls directly 
from the window's expose event handler the expose events never reach the 
box widget (they do on 2.8.x (twice, once for the extra handler I added 
and once for the normal handler) they don't on 2.4.x).

Now there are no diffs in the gtk_container_propagate_expose method 
between 2.4.14 and 2.8.6. But this method does call 
gtk_widget_region_intersect which contains some significant diffs.

To cut a long story short with gtk+ < 2.8.x we need the chaining up in 
order to set the "allocation" attribute of the box object. You can check 
this by printing out $box->allocation->values. For the working version 
of the demo script this will return valid coordinates, while the not 
working version returns -1, -1, 1, 1. Apperently the allocation 
attribute is set implicitly for gtk+ 2.8.x but needs to be set 
explicitly for older versions.

B.t.w is there a way to set such attributes (that are not properties) of 
gtk objects from perl?

Anyway I'll go on with developing zim. When I think I have a stable 
release I'll release the Gtk2::Ex:: modules to CPAN as a seperate 
package. I expect this to include HyperTextView (TextView supporting 
links) HyperTextBuffer (buffer that manages a pod parse tree) and of 
course PathBar.

Cheers!

--
   )   (     Jaap Karssenberg || Pardus [Larus]                | |0| |
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