Mailing List Archive: GTK Negative Widget Height

Hello,

I've been experiencing a problem with various programs for some time.
These programs use the GTK+ toolkit and when a particular menu is selected
from the main menu bar at the top a sub-menu of either very small height or
of no height (i.e. a thin line) will appear. Needless to say, the program
cannot be operated with such menus.

Usually, a program restart will fix the issue and restore normal menus
but sometimes several restarts are necessary. The error message that
is associated with these botched sub-menus is the following:

Gtk-WARNING **: gtk_widget_size_allocate(): attempt to allocate widget with
width 226 and height -118.

Somehow, the menu is being invoked with a _negative_ value for height, which
of course makes no sense. The resulting menu widget appears as a thin (one pixel)
horizontal line.

Through searches I've found nothing similar reported

Because this can happen with more than one program, I doubt if it is
the fault with any single package. GTK+ must be causing this.

Has anyone experienced similar behavior?

As I mentioned, a program restart usually fixes the problem. However, when
and if this problem will occur is not predictable. It happens only occasionally
and never consistently.

Frank Peters

On Tue, 18 Aug 2015 23:40:32 -0400
Frank Peters <frank.peters@comcast.net> wrote:

>
> As I mentioned, a program restart usually fixes the problem. However, when
> and if this problem will occur is not predictable. It happens only occasionally
> and never consistently.
>

I've discovered something else that seems very significant.

The behavior depends on the relation of the position of the
window in which the problem occurs in relation to other windows.
If I shift the widow around I can get different appearances
of the sub-menus from complete to very thin to a one pixel
line. Thus, the fault would seem to be with how GTK+ calculates
the window dimensions in relation to other windows. In some
cases a miscalculation will result in a negative height.

The fault could also be with the window manager which, AFAIK,
reports window positions. But then I only understand little
about the mechanisms of the X Window GUI and how window managers
and took kits interact with it.

Anyway, if the problem occurs, I just need to shift the window
to another position and that should take care of the sub-menus.

Frank Peters