To create a widget on a canvas, use the createWindow command: 
$button = $canvas->Button( -text => "Push me", 
   -command => sub { print "Been pushed\n"; });
$id = $canvas->createWindow( 0, 0, -window => $button, 
   -tags => "button1", -anchor => "center" );

[download]
Note that I have associated the tag button1 with the widget. Then I can use this tag to move the widget around: 
$canvas->move( "button1", 100, 100);

[download]
As to your type of widget, I would start out with a LabEntry box and try to configure the appearance to your liking. Note the inset box appearance is an inportant visual cue to editability and should not be lightly discarded. If you like, after the user has edited the text, your could destroy the LabEntry widget and replace it with a Label widget.

Update: Forgot to mention that the single best source for programming the perl/Tk API is the book "Mastering Perl/Tk" by Steve Lidie and Nancy Walsh. I'd stay away from the Learing Perl/Tk book. It is pretty weak for an O'Reilly book.

-Mark

In reply to Re: Tk: how to have an editable/movable label? by kvale
in thread Tk: how to have an editable/movable label? by johnnywang

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