chapman@lll-crg.llnl.gov (Carol Chapman) (04/19/91)
I recently reported (complained) to the net about problems accessing
the contents of pushbutton labels using Motif. Some of the labels
were created using UIL and some were set within my C program by a call
to XmStringCreateLtoR. Masayoshi Habu replied and told me to try
using XmStringCreate rather than XmStringCreateLtoR. That solved my
problem with labels that were set within my C program, but I am still
unable to access labels set within UIL code. I'm using XmStringGetLtR
to try to look at the contents. It always returns a null string. I
therefore suspect that XmStringCreateLtoR is buggy, and UIL is buggy
too. My work is all on DEC equipment, so I've reported the bug to
them. Enclosed here are some small test cases I ran, if anyone is
interested.
I'm using
C, VMS 5.3, and Motif 1.1 on a VAXstation 3100. The enclosed files
are: test.c, test.com, test.opt, test1.c, test1.uil, test1.com and
test1.opt. Test.c creates a label and successfully accesses it.
Test1.c uses UIL to create a pushbutton containing a label. I am not
able to access its label.
After running test and test1, I thought the problem must be related
to UIL, but I received a phone call from a guy named Sanjay
Agrawal who works for Oracle in Berkeley. He claims to have the
same problem in that his small test case works, but on his larger
real program, a null label is always returned. He is not using UIL.
carol (chapman@llnl.gov)
--------------------------------------------------------------------
/*---------------------------------------------------------------------------*/
/* TEST.C */
/*---------------------------------------------------------------------------*/
#define VMS
#include <stdio.h>
#ifdef VMS
#include <stdlib.h>
#endif
#include <X11/Intrinsic.h>
#include <Xm/Xm.h>
#include <Xm/Label.h>
#include <Xm/PushB.h>
#include <Mrm/MrmPublic.h>
#define MAX_ARGS 12
#define MAX_LABEL_SIZE 128
Boolean debug = True;
char* get_label(Widget);
/*---------------------------------------------------------------------------*/
main(int argc, char *argv[])
{
Widget toplevel, msg;
Arg al[10];
int ac;
char* label = NULL;
toplevel=XtInitialize(argv[0],"",NULL,0,&argc,argv);
ac=0;
XtSetArg(al[ac],XmNlabelString,
XmStringCreate("hello",XmSTRING_DEFAULT_CHARSET)); ac++;
msg=XtCreateManagedWidget("msg",xmLabelWidgetClass,toplevel,al,ac);
XtRealizeWidget(toplevel);
label = (char*) XtCalloc(MAX_LABEL_SIZE, sizeof(char));
label = get_label(msg);
printf("label = %s\n", label);
XtMainLoop();
}
/*---------------------------------------------------------------------------*/
char* get_label(Widget id)
/* Returns a label from within a Motif label string. */
{
int num = 0; /* number of arguments */
Arg wargs[MAX_ARGS]; /* argument list */
char* label = NULL; /* label to be returned */
XmString label_str; /* Motif label string */
if (debug)
printf("in get_label\n");
/* Pull the label out of the widget */
XtSetArg(wargs[num], XmNlabelString, &label_str); num++;
XtGetValues(id, wargs, num);
/* Pull the character string out of the XmString */
XmStringGetLtoR(label_str, XmSTRING_DEFAULT_CHARSET, &label);
/* Free string and make sure we free the pixmap (if there was one) */
XmStringFree(label_str);
if (debug)
printf("leaving get_label\n");
return(label);
} /* of get_label */
/*--------------------------------------------------------------------------*/
!---------------------------------------------------------------------------!
! TEST.OPT !
!---------------------------------------------------------------------------!
sys$share:decw$motif$dxmshr/share,-
sys$share:decw$motif$xmshr/share,-
sys$share:decw$motif$xtshr/share,-
sys$share:decw$xlibshr/share,-
sys$share:vaxcrtl/share
!-----------------------------------------------------------------------------!
! TEST.COM !
!-----------------------------------------------------------------------------!
$ link/debug test, test.opt/options
$ exit
/*--------------------------------------------------------------------------*/
/* TEST1.C */
/*--------------------------------------------------------------------------*/
#define VMS
#include <stdio.h>
#ifdef VMS
#include <stdlib.h>
#endif
#include <X11/Intrinsic.h>
#include <Xm/Xm.h>
#include <Xm/Label.h>
#include <Xm/PushB.h>
#include <Mrm/MrmPublic.h>
Display *disp; /* the display */
MrmHierarchy s_MrmHierarchy; /* our widget hierarchy */
Widget toplevel = NULL; /* top widget */
XtAppContext app_context; /* application context */
Widget widgetlist[2]; /* array of most widgets */
#define MAX_ARGS 12
#define MAX_LABEL_SIZE 128
/*---------------------------------------------------------------------------*/
void create_cb(Widget w,
int* data_from_app,
caddr_t data_from_widget)
/* A callback routine called when most widgets are first created. This
stores the id of the widget in an indexed array called widgetlist. */
{
int index = (int) *data_from_app;
widgetlist[index] = w;
} /* of create_cb */
/*---------------------------------------------------------------------------*/
char* get_label(Widget id)
/* Returns a label from within a Motif label string. */
{
int num = 0; /* number of arguments */
Arg wargs[MAX_ARGS]; /* argument list */
char* label = NULL; /* label to be returned */
XmString label_str; /* Motif label string */
printf("in get_label\n");
/* Pull the label out of the widget */
XtSetArg(wargs[num], XmNlabelString, &label_str); num++;
XtGetValues(id, wargs, num);
/* Pull the character string out of the XmString */
XmStringGetLtoR(label_str, XmSTRING_DEFAULT_CHARSET, &label);
/* Free string and make sure we free the pixmap (if there was one) */
XmStringFree(label_str);
printf("leaving get_label\n");
return(label);
} /* of get_label */
/*--------------------------------------------------------------------------*/
void set_label(Widget id,
char* label)
/* Sets a Motif label. */
{
int num = 0; /* number of arguments */
Arg wargs[MAX_ARGS]; /* argument list */
XmString label_str; /* Motif label string */
printf("in set_label\n");
/* specify the new label */
label_str = XmStringCreateLtoR(label, XmSTRING_DEFAULT_CHARSET);
XtSetArg(wargs[num], XmNlabelType, XmSTRING); num++;
XtSetArg(wargs[num], XmNlabelString, label_str); num++;
XtSetValues(id, wargs, num);
/* Free string and make sure we free the pixmap (if there was one) */
XmStringFree(label_str);
printf("leaving set_label\n");
} /* of set_label */
/*---------------------------------------------------------------------------*/
extern void the_test_cb(Widget w,
caddr_t data_from_app,
caddr_t data_from_widget)
{
char* label = NULL;
printf("in the_test_cb\n");
label = (char*) XtCalloc(MAX_LABEL_SIZE, sizeof(char));
label = get_label(widgetlist[1]);
if (label != NULL)
printf("originally, label = %s\n", label);
else
printf("originally, label is perceived to be NULL\n");
set_label(widgetlist[1], "new label");
label = (char*) XtCalloc(MAX_LABEL_SIZE, sizeof(char));
label = get_label(widgetlist[1]);
if (label != NULL)
printf("after set_label, label = %s\n", label);
else
printf("after set_label, label is NULL\n");
printf("leaving the_test_cb\n");
} /* of the_test_cb */
/*---------------------------------------------------------------------------*/
int main (argc,argv)
unsigned int argc;
char **argv;
{
MrmRegisterArg register_list[] = {
{"create_cb", (caddr_t) create_cb},
{"the_test_cb", (caddr_t) the_test_cb}
}; /* of register_list */
char* uid_files_array[] =
{ "test1.uid"
}; /* of uid_files_array */
int i = 0;
int register_list_num = (sizeof register_list / sizeof register_list[0]);
MrmCode cwin_type;
MrmType main_window_class;
Widget main_window_id = NULL;
Arg wargs[MAX_ARGS];
MrmInitialize(); /* initialize Motif Resource Manager */
/* initialize the X Toolkit */
toplevel = XtAppInitialize(&app_context,
"Test1",
NULL,
0,
&argc,
argv,
NULL,
NULL,
0);
/* open all UID files in the hierarchy and get hierarchy id */
if (MrmOpenHierarchy((MrmCount) XtNumber(uid_files_array),
uid_files_array,
NULL,
&s_MrmHierarchy) != MrmSUCCESS)
{ /* something is wrong */
printf("test1.c/main: Error opening UID file(s)\n");
exit(1);
} /* of if */
/* register UIL names that will be used by this program */
if (MrmRegisterNames (register_list, register_list_num) != MrmSUCCESS)
{ /* something is wrong */
printf("test1.c/main: Error registering names\n");
exit(1);
} /* of if */
/* fetch the main window widget */
if (MrmFetchWidget(s_MrmHierarchy,
"main_w",
toplevel,
&main_window_id,
&main_window_class) != MrmSUCCESS)
{ /* unable to fetch widget */
printf("test1.c/main: Error fetching main window widget.\n");
exit(1); /* abort program */
} /* of if */
widgetlist[0] = main_window_id;
/* manage the main window widget and its children */
XtManageChild(main_window_id);
/* let the main window widget know that the label widget is the
work window portion of the main window */
XtSetArg(wargs[0], XmNworkWindow, widgetlist[1]);
XtSetValues(widgetlist[0], wargs, 1);
/* display toplevel widget and its managed children */
XtRealizeWidget(toplevel);
/* get display value for later use */
disp = XtDisplay(toplevel);
XSynchronize(disp, TRUE); /* enable synchronization for debugging */
XtAppMainLoop(app_context); /* infinite loop for event handling */
} /* of main */
!------------------------------------------------------------------------------!
! TEST1.UIL !
!------------------------------------------------------------------------------!
module test1
names = case_sensitive
object
main_w: XmMainWindow
{
arguments
{
XmNx = 75;
XmNy = 113;
XmNborderWidth = 1;
};
controls
{
XmPushButton pbutton;
};
};
pbutton: XmPushButton
{
arguments
{
XmNx = 16;
XmNy = 4;
XmNlabelString =
compound_string("hello world");
};
callbacks
{
MrmNcreateCallback = procedures
{
create_cb(1);
};
XmNactivateCallback = procedures
{
the_test_cb(0);
};
};
};
procedure
create_cb;
the_test_cb;
end module;
!-----------------------------------------------------------------------!
! TEST1.OPT !
!-----------------------------------------------------------------------!
sys$share:decw$motif$dxmshr/share,-
sys$share:decw$motif$xmshr/share,-
sys$share:decw$motif$xtshr/share,-
sys$share:decw$xlibshr/share,-
sys$share:vaxcrtl/share
!-------------------------------------------------------------------------!
! TEST1.COM !
!-------------------------------------------------------------------------!
$ link/debug test1, test1.opt/options
$ exit
Carol Chapman Tel. (415) 423-7876
Livermore National Laboratory NEW --> chapman@.llnl.gov
P. O. Box 808, L-572 "Are you in charge here?"
Livermore, CA 94550 "No, but I'm full of ideas!" -- Dr. Who