# TIP 437: Tk panedwindow options for proxy window
	State:		Final
	Type:		Project
	Tcl-Version:	8.5.18
	Vote:		Done
	Post-History:	
	Author:		Eric Boudaillier <beric@users.sf.net>
	Author:		François Vogel <fvogelnew1@users.sf.net>
	Created:	14-Jul-2015
	Keywords:	Tk
	Tk-Branch:	tip-437
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# Abstract

The proxy window \(i.e., the moving sash\) of the Tk paned window widget is hard
to see in some circumstances.  This TIP adds three options allowing more
control over the display of the proxy so that its visibility can be enhanced
where required.

# Rationale

As identified in [Bug: 1247115, <https://core.tcl-lang.org/tk/tktview/1247115],> a
flat sashrelief is common for **panedwindow** widgets, when it separates two
widgets with sunken relief.  For example, the left part can be a tree and the
right part a text widget, both with a white background.  Under Windows, the
paned window has a light grey color, and in this configuration, the proxy
window is not well visible when it is moved over its managed widgets.

# Proposed Change

It is proposed to add three options to the Tk **panedwindow** widget:
**-proxybackground**, **-proxyrelief** and **-proxyborderwidth**.

 * **-proxybackground** controls the background of the proxy window.  If
   empty \(the default\), the background is that of the panedwindow widget,
   which is the current behaviour.

 * **-proxyrelief** controls the relief of the proxy window.  If empty \(the
   default\), the relief is that of the panedwindow widget, which is the
   current behaviour.

 * **-proxyborderwidth** controls the border width of the proxy window.  The
   default value is 2, which is the current value.

# Copyright

This document has been placed in the public domain.

