Re: Dazed and confused about menus

["muppet" <scott asofyet org>]

David Sword said:
> Everything works fine, except for attaching the callback to run the
> programs - it always contains the details of the last menuitem created,
> as opposed to the one selected, and I don't understand how to make this
> work (or even if it CAN work!)

the answer is perl scoping rules.


> sub LoadMenus{
>     my @data;
>     my @data1;
,,,
>       if($data[$cntr][1] eq 'P'){
>           $progname  = $subname;
>           $MenuItem[$cntr]->signal_connect('activate' => sub{
> \&RunProg(@_,$progname)} );
>       }else{
...
>       }
...
>     }
...
> }

$progname appears to be a global, in which case, the closure will always see
the last value set.

either use a lexical in the closure, like this:


        if($data[$cntr][1] eq 'P'){
            my $progname  = $subname;
            ^^^
            $MenuItem[$cntr]->signal_connect('activate' =>
sub{\&RunProg(@_,$progname)} );
        }else{

or pass the name string as the user data argument to the signal handler, like
this:

        if($data[$cntr][1] eq 'P'){
            # by passing subname as the user data, it will be
            # appended to the closure's @_.
            $MenuItem[$cntr]->signal_connect('activate' => sub{\&RunProg(@_)},
                            $subname );
        }else{

-- 
muppet <scott at asofyet dot org>