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TIP:		260
Title:		Add Underline Option to Canvas Text Items
State:		Final
Type:		Project
Tcl-Version:	8.5
Vote:		Done
Post-History:	
Version:	$Revision: 1.4 $
Author:		Donal K. Fellows <[email protected]>
Created:	04-Jan-2006

~ Abstract

This TIP proposes adding an '''-underline''' option to the Tk
'''canvas''' widget's text items.

~ Rationale

If you're simulating a '''label''' (or '''button''' or ...) widget
using a '''canvas''', it is useful to be able to underline a single
character of a piece of text. Although this can be done in various
ways using '''font measure''' to work out where to start drawing, it
would be far easier if we could use Tk's own built-in underlining
engine (which also gets other font-related issues correct too, and
correcting for them is more difficult than it ought to be given that
Tk already knows what to do anyway).

~ Proposed Change

The '''canvas''' widget's text items shall gain an additional option,
'''-underline''' which shall take an integer value (-1 being the
default "no underline" value) describing which character position in
the text to underline, just as with the '''-underline''' option
provided by the '''label''' widget (and elsewhere). As with all canvas
items, no specific support for modification through the option
database shall be provided, but otherwise the option shall be exactly
as described in the '''options''' manual page.

~ Copyright

This document has been placed in the public domain.