Re: User preferences

[Richard Frith-Macdonald]

On 15 Dec 2004, at 23:50, Samuel Hornus wrote:

> Hi !
>
> Being happy with my little GUI, I would like to store/retreive some  
> user
> preferences. NSUserDefaults seems the way to go, and after reading some
> (but certainly not the most relevant :-( ) documentation, I followed  
> the
> advices from this web page:
>
> http://developer.apple.com/documentation/Cocoa/Conceptual/ 
> UserDefaults/Tasks/UsingDefaults.html#//apple_ref/doc/uid/20000719

Looks fine ... nothing there which should not work in GNUstep.

> Needless to say, it does not work. I kinda feel that I may need to
> supply some "default domain name" to the NSUserDefaults, but I can't  
> see
> where/what/when/why/...

No, you don't need to supply a domain name.

> Do you have some clues about saving some prefs and retrieving them ?
> What need be added to the code examplified in the webpage above ?
> Thank you in advance !

To save -

// Set a default string in the default domain for the application
[[NSUserDefaults standardUserDefaults] setObject: @"aValue" forKey:  
@"aKey"];

// Retrieve the value from the defaults system
value = [[NSUserDefaults standardUserDefaults] objectForKey: @"aKey"];

/*
 * NB. when a default value is set, it is cached in memory and not  
written to disk until
 * later on when the run loop is running and a regular housekeeping  
timer goes off.
 * If your program exits shortly after setting a default, or if your  
program is not using
 * a run loop, you need to explicitly flush the cached default data to  
disk by calling
 * the synchronize method.  The apple documentation does talk about  
this, but perhaps
 * not as clearly as it should.
 */
[[NSUserDefaults standardUserDefaults] synchronize];