Background: I've got an array (@bit) that represents a bit field. I would like to have a menubutton whose text is the concatenation of elements 9 and 10 of this array. I want the menubutton's text to update whenever I change the values of elements 9 and 10. So the button might display 01, and then after changing bits 9 and 10 it would display 11, or 10, etc.

Here is a snippet of the code I have right now:
(I've tried a couple of variations with no luck) 
$bit_10 = \$bit[10];
$bit_9  = \$bit[9];
$bit_10_9 = $$bit_10 . $$bit_9;

$bit_10_9_mb = $r2Frame->Menubutton(
                            -textvariable => \$bit_10_9,
                            -menuitems => [['command' => "00",
                                            -command => sub {$bit[10] 
+= 0; $bit[9] = 0;}],
                                           ['command' => "01",
                                            -command => sub {$bit[10] 
+= 0; $bit[9] = 1;}],
                                           ['command' => "10",
                                            -command => sub {$bit[10] 
+= 1; $bit[9] = 0;}],
                                           ['command' => "11",
                                            -command => sub {$bit[10] 
+= 1; $bit[9] = 1;}]],
                            -background => "black",
                            -foreground => "white",
                            -tearoff => 0,
                            -relief => "groove",
                            )->pack(-side => "left", "-after" => $bit_
+11_entry);

[download]
Right now the code does indeed display the concatenation of the bits, but the button's text is never updated
from its original value whenever I change the values of bits 9 and 10.

I'm stuck! I have tried this a couple of different ways (with and w/o references) and can't get it to work.
Any help would be greatly appreciated.

In reply to Updating concatenated text on a Menubutton by Kahlua_II

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