Conference bulova::decw_jan-89_to_nov-90

2496.0. "List Box Probles (VMS 5.3)" by CESARE::ALMONDO () Thu Mar 22 1990 06:20

  Hello,

  I have a problem with the list box widget on VMS 5.3-1.
  The list box appears on the screen but , when the items are added the
  scroll bar change but no items are displayed. 

  The same code run correctly if compiled on a 5.2 VMS or on ULTRIX.

  Mario Almondo
  CIM-Int. Engineering
  Turin (Italy)
 
  Thanks in advance.

  the following is the code used to add the items : 

 
/********************************************************************
*                                                                   *
*   AddLine  function :                                             *
*       Add a New Line on a list box widget.                        *
*                                                                   *
*       Parameters :                                                *
*                                                                   *
*           w      (Widget) Widget id of the ListBox.               *
*           txt    (char *) text to be added.                       *
*           pos	   (int) position for insertion			    *  *********************************************************************/
static void AddLine(w,txt,pos)
Widget w;
char *txt;
int pos;
{

        DwtCompString list_txt;

        list_txt = DwtLatin1String(txt);
	DwtListBoxAddItem(w,list_txt,pos);
        XtFree(list_txt);
}

......

if (!count) {
        if ((ret = DwtFetchWidget (s_DRMHierarchy,
        			   SHOW_WIDGET,toplevel,
                                   &widgets[k_list_popup],
                                   &class))  != DRMSuccess )
                {
                        printf("error creating %s widget\n",LIST_WIDGET);
                        return(-1);
                }
                txt = DwtLatin1String("list box widget tester");
                SetValue(widgets[k_var_name_lab],DwtNlabel,txt);
                XtManageChild(widgets[k_show_box]);
        }
        else
        {
                sprintf(str,"list element number %d",count);
                AddLine(widgets[k_list_list],str,0);
        }
.......

Widget is created usin the following uil; definition :

.....

value
 FIXED_SPC : font('-DEC-Terminal-Bold-R-Normal--14-140-75-75-C-8-ISO8859-1');

object
    show_box : popup_attached_db {
        arguments {
            title                     = k_showbox_title;
            default_vertical_offset   = 4;
            default_horizontal_offset = 4;
        };
        controls {
            label       name_label;
            list_box    elements_list;
            push_button return_but;
        };
        callbacks {
          create = procedure creation (k_list_popup);
        };
};

object
    name_label  : label {
        arguments {
           adb_top_attachment   = DwtAttachAdb;
           adb_top_offset       = 10;
           adb_left_attachment  = DwtAttachAdb;
           adb_right_attachment = DwtAttachAdb;
           label_label          = label_name;
        };
        callbacks {
           create = procedure creation (k_var_name_lab);
        };
};

object
    elements_list : list_box {
        arguments {
           width                        = 300;
           visible_items_count          = 5;
           create_horizontal_scroll_bar = true;
           single_selection             = true;
           font_argument                = FIXED_SPC;
           margin_height                = 5;
           margin_width                 = 5;
           adb_top_attachment           = DwtAttachWidget;
           adb_top_widget               = label var_name_label;
           adb_left_attachment          = DwtAttachAdb;
        };
        callbacks {
           single = procedure selection (k_list_box);
           create = procedure creation (k_list_box);
        };
};