Configuration Files and Tkinter--Possible?

[Gabriel Genellina]

En Wed, 04 Mar 2009 03:13:43 -0200, W. eWatson <notvalid2 at sbcglobal.net>  
escribió:

> I'm converting a Tkinter program (Win XP) that uses widgets that allows  
> the user to change default values of various parameters like start and  
> stop time in hh:mm:ss, time of exposure in seconds, and whether certain  
> options should be on or off. The initial values are set in the code. I  
> can pretty well modify matters, so the values of parameters can be saved  
> and restored from a config file for use outside the widgets (dialogs).  
> Basically, a list of parameter names and values are kept in the file.

Do you want to build a generic dialog (that is, do you want to *build* the  
dialog depending on what you find in the file)? Or does the dialog already  
exist? (In the former case, if you add a new parameter in the file, a new  
widget -of an adequate type- is created)
I assume this is not the case, and you have a fixed dialog containing a  
known set of widgets that represent a known set of parameters.

You need some object that stores the config values, and read/save them  
 from the config file. And a dialog that shows the config info and let the  
user modify it. You don't need any StringVar/IntVar/whatever, if you don't  
have to "track" changes to the variables (by example, a "zoom" slider  
might provide feedback by zooming the image).
So in the "Options..." menu item in your application, you:

	- create the dialog with the required widgets.
         - call a method .setvalues(config) which receives a config object  
with all the settings, and assigns them to each corresponding widget.
         - have a method .getvalues(config) that does the inverse  
operation: from widget contents into the config object.
         - display the dialog (you must use a modal loop; see  
http://effbot.org/tkinterbook/tkinter-dialog-windows.htm ). If you use  
tkSimpleDialog, make sure the .apply() method calls .getvalues
	- on exit, the config object contains the final values.

-- 
Gabriel Genellina