Question:

1. I have created a table dynamically using a for loop in Tcl/Tk.
2. One of the columns in the table is a column of buttons
3. All the buttons call the same action proc as the each do something similar

How can I set up the buttons so that I know which was pressed in the action proc?

Answer:

Pass in a parameter to the proc that includes the button number.

Example:

  proc report {value} {
    puts "Pressed button $value"
    }
  for {set k 1} {$k < 6} {incr k} {
    button .x$k -text "Button $k" -command "report $k"
    pack .x$k
    }
  button .quit -text Exit -command exit
  pack .quit


(written 2012-01-12, updated 2012-01-14)

 T224 - Tcl/Tk - Events in Tk
  [386] What is a callback? - (2005-07-22)
  [1473] Making a variable dynamically visible in a Tcl/Tk GUI - (2007-12-15)
  [4258] Keeping you Tkinter display up to date while monitoring - (2014-04-06)

T217 - Tcl/Tk - First Widgets, Geometry and Events
  [309] Writing a Tcl/Tk GUI is as easy as baking a cake - (2005-05-12)
  [3415] User defined sorting and other uses of callbacks in Tcl and Tk - (2011-09-02)
  [4458] A new Tcl/tk example - a window to show system status - (2015-03-11)

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