Training, Open Source Programming Languages

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For 2021 - online Python 3 training - see ((here)).

Our plans were to retire in summer 2020 and see the world, but Coronavirus has lead us into a lot of lockdown programming in Python 3 and PHP 7.
We can now offer tailored online training - small groups, real tutors - works really well for groups of 4 to 14 delegates. Anywhere in the world; course language English.

Please ask about private 'maintenance' training for Python 2, Tcl, Perl, PHP, Lua, etc.
Making a variable dynamically visible in a Tcl/Tk GUI

set bill "and Ben"
label .about -textvariable bill
button .first -text "First" -command {set bill Bradshaw}
button .second -text "Second" -command {set bill Bailey}
button .done -text quit -command exit
pack .about .first .second .done

Tcl/Tk's -textvariable option, on commands like label and button, allows you to have the contents of a variable display within you GUI (Graphic User Interface) ... and simply changing the value in the variable will change your display.

Quick, elegant, easy to program and easy to maintain.
(written 2007-12-15, updated 2007-12-16)

 
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
T224 - Tcl/Tk - Events in Tk
  [386] What is a callback? - (2005-07-22)
  [3575] Multiple buttons calling the same proc in wish (tcl/tk) - (2012-01-12)
  [4258] Keeping you Tkinter display up to date while monitoring - (2014-04-06)


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Using Tcl/Tk resource files for flexible applications
Some other Articles
Decisions - small ones, or big ones?
Shopping for Christmas and looking forward
Tcl/Tk - updating your display while tasks are running
Using Tcl/Tk resource files for flexible applications
Making a variable dynamically visible in a Tcl/Tk GUI
The Horse goes on and on
Cliff Lift simulator- Lynton to Lynmouth - in Tcl/Tk
fill and expand on Tcl/Tk pack command
Curley brackets v double quotes - Tcl, Tk, Expect
Lexical v Arithemetic testing, Bash and Perl
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This is a page archived from The Horse's Mouth at http://www.wellho.net/horse/ - the diary and writings of Graham Ellis. Every attempt was made to provide current information at the time the page was written, but things do move forward in our business - new software releases, price changes, new techniques. Please check back via our main site for current courses, prices, versions, etc - any mention of a price in "The Horse's Mouth" cannot be taken as an offer to supply at that price.

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