I'm sure I've read somewhere, that you can somehow freeze a widget while you update it and show it afterwards, but I forgot where and how.

I'm not sure what you mean, do you want to store the data from the ListBox using Storable, for example? 

use Storable;
tie $hashref, "Tk::Listbox", $lbox, {'ReturnType' => 'both'};
store $hashref, 'file';
...
$hashref = retrieve('file');

[download]

Do you want to hide the widget? $listbox->packForget();

Or, do you want to store the configuration of the widget? 

use Storable;
@columninfo = $mlistbox->columnPackInfo();
store \@columninfo, 'file';

[download]

The next question concerns the alignment of the Listbox entries. They are left aligned by default. How can I change this to right or center aligned?

# "-anchor" specifies how the information in a widget (e.g. 
# text or a bitmap) is to be displayed in the widget. Must 
# be one of the values n, ne, e, se, s, sw, w, nw, or 
# center. For example, nw means display the information 
# such that its top-left corner is at the top-left corner 
# of the widget. 

$mlistbox->configure(-anchor => 'e'); # or 'center'

[download]

--
hiseldl
What time is it? It's Camel Time!

In reply to Re: Tk::Listbox: 2 questions: performance and alignment by hiseldl
in thread Tk::Listbox: 2 questions: performance and alignment by busunsl

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