ATTN: Perl maintainer - RE: Problem with Perl/Tk and Pixmap

["Thrall, Bryan" <bryan dot thrall at flightsafety dot com>]

Thrall, Bryan wrote on 2010-12-16: 
> Andrew DeFaria wrote on 2010-12-16:
>>   On 12/16/2010 02:07 PM, Johannes v. Löwis wrote:
>>> I have a Perl/Tk script that is supposed to show a pixmap on the left
>>> side of the title bar of the main window. It works on Linux and on a
>>> rather old version of Cygwin 1.5. On Cygwin 1.7 (on XP Home and Prof)
>>> the following happens:
>>> 
>>> $ ./logotest.pl Can't bless non-reference value at
>>> /usr/lib/perl5/vendor_perl/5.10/i686-cygwin/Tk/Image.pm line 23. ...
>>> Any ideas or suggestions what further information I could provide in
>>> order to sort this out?
>>> 
>> Reproduced. Note you problem appears to be with Tk::Image, not with
>> Cygwin, though you are right in that it works on Linux and complains
>> and dies on Cygwin.
>> 
>> Interestingly, if you run your program and the Perl debugger (i.e. perl
>> -d logtest.pl) then simply type c for continue it works fine.
>> 
>> Looking at Image.pm I see that if I break at Image.pm:23 there's a
>> "return bless $obj,$package" statement. In the debugger, $obj is
>> defined and there's no problem. If, however, I just run this without
>> the debugger, but put some print statements in Image.pm, I see that
>> $obj is indeed returned from $widget->Tk::image as undefined.
>> 
>> This appears to be a Perl/Tk bug.
>> 
>> Even stranger! Change your
>> 
>>    $mw->Pixmap('logo', -data=>$icon);
>> to
>> 
>>    my $foo $mw->Pixmap('logo', -data=>$icon);
>> and it works! So you have  a work around, and a bug to report.
> 
> I also can reproduce the problem.
> 
> This behavior reminds me of a perl-Tk packaging bug from last year:
> 
> http://www.cygwin.com/ml/cygwin/2009-07/msg00890.html
> 
> In fact, /usr/bin/widget seems to be broken again, unless you run it in
> the perl debugger:
> 
> thrall@pc1163-8413-xp ~
> $ /usr/bin/widget
> Can't set -labelFont to `Courier 12 bold' for
> Tk::LabEntry=HASH(0x1067dac0): unknown option "-labelFont" at
> /usr/lib/perl5/vendor_perl/5.10/i686-cygwin/Tk/Derived.pm line 294.
> 
>  at /usr/lib/perl5/vendor_perl/5.10/i686-cygwin/Tk/Derived.pm line 306
> thrall@pc1163-8413-xp ~
> $ cygcheck -cd perl perl-Tk
> Cygwin Package Information
> Package              Version
> cygwin               1.7.7-1
> perl                 5.10.1-4
> perl-Tk              804.029-1
>

It seems I have unfairly blamed Perl-Tk for these problems; reverting to perl-5.10.1-3 fixes both the OP's Pixmap problem and the widget problem on my machine.

Hope this helps,
--
Bryan Thrall
FlightSafety International
bryan.thrall@flightsafety.com
? 



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