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From: grp@Unify.com (Greg Pasquariello)
Newsgroups: comp.windows.x
Subject: Re: X/OLIT question
Message-ID: <1991Mar5.093828@Unify.com>
Date: 5 Mar 91 17:38:28 GMT
References: <fm.668135416@neptune>
Sender: news@Unify.Com (news admin)
Reply-To: grp@Unify.com (Greg Pasquariello)
Organization: Unify Corporation, Sacramento, CA, USA
Lines: 110

In article <fm.668135416@neptune>, fm@neptune.iex.com (Mohammad Faroog) writes:
> 
> I have just started programming in X. I came accross a couple of problems. 
> Is there anyone who can explain me why it is not doing what I think it
suppose
> to do.
> 
> I am using textfield widget of openlook intrinsics toolkit. What I want to do
> when ever pointer is in the field and if user presses any key widget should
call
> application supplied function. As you know textfield widget doesn't offer 
> any call back of that kind. So I tried to solve this problem by to different
> methods. 

Your problem is that you are installing the event handler on the wrong 
widget.  The TextField widget is made up of a sub-widget called the
TextEdit widget.  You need to get the id of that sub-widget, and install
the event handler on it.  The id of the sub-widget can be had by getting
the resource XtNtextEditWidget on the TextField.

I have modified your example slightly to demonstrate.  The modifications
are marked with comments.

> 
> 1- I used XtAddEventHandler()
> 
> 1- I modified widget's translation table.
> 
> Method - 1 code example :
> 
> #include <stdio.h>
> #include <errno.h>
> 
> #include <X11/Intrinsic.h>
> #include <X11/StringDefs.h>
> 
> #include <Xol/OpenLook.h>
> #include <Xol/ControlAre.h>
> #include <Xol/TextField.h>
> #include <Xol/Form.h>
> #include <Xol/Caption.h>
> 
> myhandler()
> {
> 	fprintf(stderr,"hello world");
> }
> 
> void main(argc, argv)
> unsigned int argc;
> char *argv[];
> {
> 
	Arg	warg;			/* MODIFICATION */
	Widget	subWid;			/* MODIFICATION */

> 	Widget w_toplevel, w_form, w_text, w_caption;
> 
> 	w_toplevel = OlInitialize(
> 		NULL, 				/* app name - filled by Xt */
> 		"Event", 			/* app class */
> 		NULL,				/* option list */
> 		0,					/* # of options */
> 		&argc, 				/* addr of main argc */
> 		argv				/* main argv */
> 	);
> 
> 	w_form = XtVaCreateWidget(	/* create form widget */
> 		"form",
> 		formWidgetClass,
> 		w_toplevel,
> 		XtNxResizable,FALSE, XtNyResizable, FALSE, NULL
> 	);
> 
> 	w_caption = XtVaCreateManagedWidget(
>        	"fieldLabel",
>        	captionWidgetClass,
>        	w_form,
>        	XtNlabel,   "File Name:", 0
>     	);
> 
> 	w_text = XtVaCreateManagedWidget(
> 		"textfield",
> 		textFieldWidgetClass,
> 		w_caption, 
> 		XtNwidth,    200,
> 		NULL
>      	);

	XtSetArg(wargs, XtNtextEditWidget, &subWid); 	/* MODIFICATION */
	XtGetValues(w_text, warg, 1);			/* MODIFICATION */
	
	XtAddEventHandler(subWid, KeyPressMask,		/* MODIFICATION */
			  FALSE, myhandler, NULL);

> 
> 	XtManageChild(w_form); 
> 	(void) XtRealizeWidget(w_toplevel);
> 
> 	(void) XtMainLoop();
> }
> 
> Mohammad Farooq.
> 
> address: fm@iex.com

--

---
Greg Pasquariello	grp@unify.com
Unify Corporation 	Be good and never poison people