wraplength and dynamically-sized widgets

[Óscar Fuentes]

From the man page:

Command-Line Name: -wraplength
Database Name: wrapLength
Database Class: WrapLength

For widgets that can perform word-wrapping, this option
specifies the maximum line length. Lines that would
exceed this length are wrapped onto the next line, so
that no line is longer than the specified length. The
value may be specified in any of the standard forms for
screen distances. If this value is less than or equal
to 0 then no wrapping is done: lines will break only
at newline characters in the text.

Apparently there is no provision for adapting the wraplength to the
width of the widget, as it is resized.

Any trick to achieve this? I'm thinking on binding to Configure and
assigning -wraplength from there, but I'm afraid of infinite loops or
redisplay problems.

[Donald Arseneau]

Óscar Fuentes <o...@wanadoo.es> writes:

> Apparently there is no provision for adapting the wraplength to the
> width of the widget, as it is resized.

I have this snip of old code handling it. You'll have to replace some
hard-coded specific values though, like the font name and the "- 9".

# for resizes, use the resized-size for wrapping
set ww [expr { [winfo width $statwin.rs_htitles_l] - 9 }]
if { $ww < 100 } { # for initialization when there's no width yet, use the preference value
set pitch [expr { 0.1*[font measure muMonoFont {1234567890}] }]
set ww [expr { int( $::PREF::textWidthMax*$pitch + 0.9 ) }]
}
$statwin.rs_htitles_l configure -wraplength $ww

> Any trick to achieve this? I'm thinking on binding to Configure and

That is in a proc bound to Configure,

Donald Arseneau as...@triumf.ca

[Óscar Fuentes]

Donald Arseneau <as...@triumf.ca> writes:

Thanks.

As I don't understand the purpose of the `if { $ww < 100 .. ' the
solution was reduced to

bind $widget <Configure> \
{%W configure -wraplength [expr {[winfo width %W] - 4}]}

which seems to work fine.

The -4 above (as your -9) is crucial. Without it the text becomes
invisible for some combinations of text width and ttk::label width.

Thanks again.