I spent multiple hours last night attempting to figure out just precisely how scrollbars work...I've read the documentation that comes with Tk along with looking at some books and I can't get a scrollbar to work with a fixed-size Canvas. I seem to be missing something...here are some examples of the code I've tried(This list is relatively long):

   # $main is MainWindow
   my $canvas = $main->Scrolled('Canvas',
                                -scrollbars => 'e', 
                                -height => 200, 
                                -width => 200,
   )->pack;
   $canvas->packPropagate(0);

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Running this code produces a very thin window with no contents. Adding
   -scrollregion => [0,0,200,200],

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to the arguments given to Scrolled produces the same output.
Going about things in a slightly different way produces a window of the correct size: 
   my $frame = $main->Scrolled('Canvas',
                                -scrollbars => 'e', 
   )->pack;
   my $canvas = $frame->Subwidget('canvas');
   $canvas->configure(-height => 200, -width => 200);
   $canvas->packPropagate(0);

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Yet, when I insert some widgets, and just to test it lets add in 
   foreach (1..20) {
      $canvas(or $frame)->Label(-text => 'test')->pack;
   }

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the contents of the canvas obviously exceed its specified height yet the scrollbar doesn't let me scroll up/down. Adding -scrollregion => [0,0,200,200] to the arguments given to configure affects nothing.

In a final attempt to get a scrollbar to work with my canvas, I tried using the Scrollbar method: 
   my $canvas = $main->Canvas(-height => 200,
                              -width => 200,
   )->pack(-side => 'left');
   $canvas->packPropagate(0);
   my $scrollbar = $main->Scrollbar(
                           -orient => 'vertical',
                           -command => ['yview' => $canvas],
   )->pack(-fill => 'y', -side => 'right');

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Clicking on the scrollbar yields a slew of error messages. I've tried a few different lists in the -command option including 
   ['yview', $canvas, 'scroll', 1, 'units']

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and to no avail. Any help here would be appreciated. I am assuming that I am missing something that is very simple here, possibly a need to inform the Canvas of the Scrollbar or something. I've looked online yet can only find examples of Scrollbars used with Listboxes, thus not helping me here. Thank you,
-Eric

In reply to A Canvas and a Scrollbar with Tk by Silverstrike

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