Example 6-1. Calculator Client with GUI C Source

#include <orb/orbit.h>
#include "calculator.h"

void
add_it(GtkWidget* o, CORBA_Environment* ev)
{
   GtkWidget* e1;
   GtkWidget* e2;
   GtkWidget* res;
   CORBA_double d1;
   CORBA_double d2;
   CORBA_double d3;

   /*
    extract the values from the e1, e2 entry fields.
    convert the strings to double values and assign these
    values to d1, d2 respectivly
    从 e1, e2 录入字段中提取出数值。典型的，
    把字符串转换成双精度数值，再把这两个值赋给 d1, d2 
   */
   
   res = Calculator_add(d1, d2, ev);
   
   /*
    convert res to a string and display it in the
    res widget
    把 res 转换成字符串并在 res 构件上显示
   */
}

   

GtkWidget*
create_gui(CORBA_Object server)
{
   /*
     create the gui with all the elemts.
     e1 is the entry widget for the first value;
     e2 is the entry widget for the second value;
     res is the widget to display the result;
     b_add is the button to add the two values;
     b_sub is the button to subtract the two values;
     window is the top level window 
     建立 GUI 及其所有的成员。
     e1 是第一个数值的录入构件
     e2 是第二个数值的录入构件
     res 是显示结果的的构件
     b_add 是加两个值的按钮
     b_sub 是减两个值的按钮
     window 是顶层窗口
  */

  /*
   * create all the widgets and place them in the window
   * 建立所有构件并放置在窗口上
   */
  ......
  gtk_object_add(b_add, "calc-server", server);
  gtk_object_add(b_add, "e1", e1);
  gtk_object_add(b_add, "e2", e2);
  gtk_object_add(b_add, "res", res);

  gtk_object_add(b_sub, "calc-server", server);
  gtk_object_add(b_sub, "e1", e1);
  gtk_object_add(b_sub, "e2", e2);
  gtk_object_add(b_sub, "res", res);

  gtk_signal_connect(b_add, "clicked", add_it, 0);
  gtk_signal_connect(b_sub, "clicked", subtract_it, 0);
  return hbox;
}


int
main(int argc, char* argv[])
{
        CORAB_Environment env;
	CORBA_ORB         orb;
	CORBA_Object      server;
        CORBA_double      res;
        GtkWidget*        app;
        gchar*            dummy_argv[2]
        gint              dummy_argc;

	CORBA_exception_init(&ev);
        dummy_argc = 1;
        dummy_argv[0] = argv[0];
        dummy_argv[1] = 0;
	orb = gnome_CORBA_init("simple-calculator", NULL, &dummy_argc, dummy_argv, 0, NULL, &ev);
	server = CORBA_ORB_string_to_object(orb, argv[1], &ev);
        app = create_gui(server);
        gtk_widget_show_all(app);
        gtk_main();
	exit(0);
};