[Tcl-bugs] [ tktoolkit-Bugs-1905656 ] Asking the width of a textwidget don't work like expected.

[SourceForge.net <no...@so...>]

Bugs item #1905656, was opened at 2008-03-02 04:07
Message generated for change (Comment added) made by nobody
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=112997&aid=1905656&group_id=12997

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: 18. [text]
Group: None
Status: Closed
Resolution: Invalid
Priority: 5
Private: No
Submitted By: Holger Ewert (ewerth)
Assigned to: Joe English (jenglish)
Summary: Asking the width of a textwidget don't work like expected.

Initial Comment:
The following code returns allways the same value (80) for '.t cget -width' even after resizing the window:

 text .t
 pack .t -fill both -expand 1
 update
 wm geometry .       ;# returns 644x388 ...
 .t cget -width      ;# returns 80
 .t configure -width ;# returns -width width Width 80 80

 .t insert end [string repeat a 200]
 update
 wm geometry .       ;# returns 644x388 ...
 .t cget -width      ;# returns 80
 .t configure -width ;# returns -width width Width 80 80


 # resize window with mouse
 update
 wm geometry .       ;# returns 644x388 ...
 .t cget -width      ;# returns 80
 .t configure -width ;# returns -width width Width 80 80

 wm geometry . 1000x500
 update
 wm geometry .       ;# returns 1000x500
 .t cget -width      ;# returns 80
 .t configure -width ;# returns -width width Width 80 80

On the other side: Modifying the width with -width works:

 text .t
 pack .t -fill both -expand 1
 update
 wm geometry .       ;# returns 644x388 ...
 .t cget -width      ;# returns 80
 .t configure -width ;# returns -width width Width 80 80

 .t insert end [string repeat a 200]
 update
 wm geometry .       ;# returns 644x388 ...
 .t cget -width      ;# returns 80
 .t configure -width ;# returns -width width Width 80 80

 .t configure -width 120
 update
 wm geometry .       ;# returns 964x388 ...
 .t cget -width      ;# returns 120
 .t configure -width ;# returns -width width Width 80 120

 .t configure -width 80
 update
 wm geometry .       ;# returns 644x388 ...
 .t cget -width      ;# returns 80
 .t configure -width ;# returns -width width Width 80 80


I tried this with ActiveTcl 8.5.1.0, ETcl 1.0-rc25 und Etcl 1.0-rc23. This means this happens on Tcl 8.4 and 8.5.
 

----------------------------------------------------------------------

Comment By: Nobody/Anonymous (nobody)
Date: 2008-03-03 05:26

Message:
Logged In: NO 

The thing with the "desired width" is something strange. Everytime we use
"configure option value" the value is an desired value. If the widget uses
this value it becomes the actual value. Changing the textwidget size with
the mouse should like using "configure -width width". In both situations we
ask the textwidget to change his width. And in both situations I expect
that "cget -width" returns the actual value. If we say there is a different
between this two situations, this means the textwidget should never change
its size, when user tries to change it with the mouse. Because the
programmer has desired the -width and there is no reason not to use the
value. In fact we have at least an unclear documentation.


----------------------------------------------------------------------

Comment By: Joe English (jenglish)
Date: 2008-03-02 21:53

Message:
Logged In: YES 
user_id=68433
Originator: NO

The -width option specifies the application's desired width in characters,
not the actual width of the widget.

The widget uses this value (and the -font, and other options) to request a
width in pixels to its geometry manager.  (Use [winfo reqwidth] to see the
widget's requested width).

The actual width is determined by the geometry manager once geometry
propagation completes.  [winfo width] returns the actual width in pixels of
the widget.  The widget may end up larger or smaller than [winfo reqwidth],
e.g., if the user resizes the window.  This does not change the value of
the '-width' option.

IOW: this is behaving as expected.  (Most Tk widgets with -width and
-height options work this way - the options specify a desired size, they
don't reflect the actual size.)

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=112997&aid=1905656&group_id=12997