From: Markus Liebelt <markus.liebelt@...>
Date: 2005-07-02T21:20:45+09:00
Subject: Re: Problem in binding IWidget combobox to event

Hello Hidetoshi,

exactly what I was looking for. Seems a lot cleaner and more fitting to  
MVC what I was looking for.

Thank you a lot

Markus

On Tue, 28 Jun 2005 17:52:32 +0200, Hidetoshi NAGAI  
<nagai@ai.kyutech.ac.jp> wrote:

> From: "Markus Liebelt" <markus.liebelt@online.de>
> Subject: Problem in binding IWidget combobox to event
> Date: Tue, 28 Jun 2005 23:05:40 +0900
> Message-ID: <op.ss21fixc444ivd@localhost>
>> I managed lately to include an iwidget combobox in a UI I have written.  
>> If
>> normally used (by poking around with the mouse) everything works fine.
>> What I cannot manage if the user is using the keyboard.
>     (snip)
>> If you open that application, and drop down with the mouse and select  
>> with
>> the mouse, you see on $stdout your selection. If you open in any way,  
>> but
>> select then by using TAB (focus goes to drop down list) and ENTER, your
>> selection goes into the combo box, but is not reflected in the $stdout.
>
> It seems a specification limit of an iwidget combobox.
>
>> What do I have to get a binding for the different possibilities to use  
>> the
>> combo box? Or is there even an easier way, eg. by using a binding to the
>> variable that lays behind the combo box?
>
> TkVariable#trace will be able to help you. Possibly, that is more
> simple than getting the listbox component and binding to it.
> For example,
> -----------------------------------------------------------
> class Ex_Combo
>    def build_form(root)
>      frame = self.create_frame(:form, root)
>      var = TkVariable.new
>      cb1 = Tk::Iwidgets::Combobox.new(frame, #:labeltext=>'Example:',
>             #:selectioncommand=>proc{puts cb1.get_curselection;  
> $stdout.flush},
>             :textvariable=>var,
>             :editable=>false)
>      var.trace('w'){
>        # This is called twice when selecting an item.
>        # One is when clearing the entry and the another is when setting
>        # a new value to it.
>        # The following check is the one to ignore clearing step.
>        unless (val = var.value).empty?
>          puts val
>          $stdout.flush
>        end
>      }
>      cb1.insert_list('end', *['First entry','Second entry','Third  
> entry'])
>      cb1.grid('row'=>0, 'column'=>0, 'sticky'=>'news')
>      frame.pack('side'=>'left', 'expand'=>'yes')
>    end
> end
> -----------------------------------------------------------



-- 
Markus Liebelt; markus.liebelt@online.de