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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
  [4258] Keeping you Tkinter display up to date while monitoring - (2014-04-06)
  [3575] Multiple buttons calling the same proc in wish (tcl/tk) - (2012-01-12)
  [386] What is a callback? - (2005-07-22)


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Using Tcl/Tk resource files for flexible applications
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Using Tcl/Tk resource files for flexible applications
Making a variable dynamically visible in a Tcl/Tk GUI
The Horse goes on and on
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