Re: Possible row selection interfering with Update

[muppet <scott asofyet org>]

On Mar 27, 2010, at 5:19 PM, Zettai Muri wrote:

> Hi All,
>
> Please find attached my main.pl file along with the GtkBuilder file I have the gui in.  I couldn't think of 
> a great example but it is using the same code and widget types in my main project.
>
> I am running the program on Windows XP with camelbox installed as 'perl main.pl'
>
> The problem is that only the shopper name updates not all of the new information entered into the text 
> views.  I have to re-select the line, re-enter the new information in the text views and then it updates 
> the second time around.  It's easier to see if you run the program.
>
> To Reproduce:

[snip excellent instructions, thanks]


> Hope you can see what I'm talking about.  It only occurs on the first attempted update click.
>
> Is someone able to tell me what I'm doing wrong?  Can't work out why the first time the update click only 
> captures the shopper name but then works the second time with the shopper name and the info entered into 
> the text views.


I could reproduce the behavior by following the instructions exactly.  Initially, i clicked around a bit 
before following the instructions, and it seemed fine.

You're changing the selection mode on the first update.  By moving the $treeselect->set_mode('single') line 
from update_line() to init(), i could no longer get the "first time it acts weird" behavior.  Doubtless, 
changing the mode causes the iter to be different.

I was also getting some warnings on stdout.

*** unhandled exception in callback:
***   variable not allowed to be undef where GtkTreeIter is wanted at main.pl line 262.
***  ignoring at main.pl line 66.

It's best not to ignore those.  ;-)


After moving the tree selection setup to init, you may be interested in using the two-return form of 
get_selection() and adding error checking:

    my ($model, $iter) = $treeselection->get_selected;
    return unless $iter;

The lines

    # Update the view
    $tv_items->set_model($model);

are not actually necessary; if you were swapping out the model to freeze updates, then that would be 
necessary, but you're not, so it's not.  In fact, the set_value calls immediately above are enough to make 
everything Just Work.


Oh, and in connect_signals(), you have each "clicked" handler getting $widget and $event off the stack; but 
there's no $event parameter to the "clicked" signal.


--
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