From: Harry Ohlsen <harryo@...>
Date: 2001-09-02T13:31:05+09:00
Subject: [ruby-talk:20689] Ruby/Tk debugging tips

I have a piece of code I wrote that implements a dialog box (basically, 
it's a frame with a bunch of labels and a single button in it).

Clicking on any of the labels works fine and I can destory the frame and 
call a block passed to the code.

However, when I click the button, which executes precisely the same type of 
code (except that it doesn't need to call the block), I get the following 
error:

   invalid command name ".w0021.w0060"
       while executing
   "$w cget -relief"
       (procedure "tkButtonDown" line 3)
       invoked from within
   "tkButtonDown .w0021.w0060
   "
       (command bound to event)

I have a feeling it has something to do with destroying the frame that 
holds the button before the button up event occurs.  I assume what this 
means is that I should really be handling binding to some other event (ie, 
whatever event happens when the button is released (which is what I thought 
binding to "1" did, but I assume that's wrong).

In any case, if someone can suggest what's going wrong or any general ideas 
on how to debug stuff like this (since the trace back doesn't show any of 
my own code), I'd appreciate it.

Thanks in advance.