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From: staatsvr@asdcds.cds.wpafb.af.mil (Vern Staats; ASD/SCED;)
Newsgroups: comp.windows.x
Subject: Re: Visuals, colors, resource db
Summary: program-specific defaults  vs.  app-defaults file
Message-ID: <274@nap1.cds.wpafb.af.mil>
Date: 25 Aug 89 18:41:05 GMT
References: <ADO.89Aug25115032@hutcs.hut.fi>
Sender: news@nap1.cds.wpafb.af.mil
Reply-To: staatsvr@asdcds.UUCP (Vern Staats)
Organization: US. Air Force, ASD, Wright-Patterson AFB
Lines: 66

In article <ADO.89Aug25115032@hutcs.hut.fi> ado@hutcs.hut.fi (Andre Dolenc) writes:
>>>   Resource database question: I have an application-dependent resource
>>>   db which I would like to merge with the one returned by XtDatabase.
>>  How about using an app-defaults file instead?  This way the toolkit
>>  will merge your resources in for you.
> Yes, I thought of that. But I have at least 2 resource files which
> must be loaded; one of them is (human) language dependent.

I have a similar question on X Philosophy and resource databases:
Should program-specific defaults for resources be rigorously avoided,
or are they OK provided they have the absolute rock-bottom precedence?  
I get the feeling that requiring an app-defaults file is the 
"philisophically correct" thing to do, but I'd really prefer 
to have my applications stay somewhat sane in its absence.

Here's what I'm doing.  I think its OK, please zap me if its wrong.

------------------------------------------------------------------------
main() {  ...
    XtToolkitInitialize();
    dpy = XtOpenDisplay((XtAppContext) NULL,displayname,app_name,app_class,
                        opTable,opTableEntries,&argc,argv);
    toplevel = XtAppCreateShell(app_name,app_class,topLevelShellWidgetClass,
                                dpy,top_args,XtNumber(top_args));
    merge_default_prefs();
    ...
}

/*  Adds application-specific hardcoded defaults to current database,
**  at a lower precedence than the existing database.
*/
merge_default_prefs()
{
    int                 i;
    static XrmDatabase  finalDB = NULL;
    XrmDatabase         currentDB;
    static char         *pgmdefaults[] = {
        "*button.background:        gray50\n",
        "*button.foreground:        cyan\n",
        /* and etc  */
        };

    for (i=0; i < sizeof(pgmdefaults) / sizeof(char *); i++)  {
        XrmPutLineResource(&finalDB,pgmdefaults[i]);
        }

    currentDB = XtDatabase(dpy);
    XrmMergeDatabases(currentDB,&finalDB);
    /* so now the currentDB (from .Xdefaults, etc) has overwritten my
       pgmdefaults in finalDB.  Now all we have to do is install finalDB.
    */

    /*  Which of these is better form?  Peeking at Xlib.h and Xresource.h:
    */
        dpy->db = finalDB;

    /*  or this?:
        currentDB = XtDatabase(dpy);
        XrmMergeDatabases(finalDB,&currentDB);
    */
}

----
INET:  staatsvr@asd.wpafb.af.mil   Vern Staats  (513) 255-2714        /// Save
UUCP:  nap1!asd!staatsvr           ASD/SCED                       \\\/// The
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