helm/DEVEL/mathml_editor/test/guiGTK.c

   1 /*
   2  * Copyright (C) 2000, Luca Padovani <luca.padovani@cs.unibo.it>.
   3  *
   4  * This file is part of GtkMathView, a Gtk widget for MathML.
   5  *
   6  * GtkMathView is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * GtkMathView is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with GtkMathView; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  19  *
  20  * For details, see the GtkMathView World-Wide-Web page,
  21  * http://cs.unibo.it/~lpadovan/mml-widget, or send a mail to
  22  * <luca.padovani@cs.unibo.it>
  23  */
  24
  25 #include <config.h>
  26 #include <stdio.h>
  27 #include <gtk/gtk.h>
  28 #include <gdk/gdkkeysyms.h>
  29
  30 #include <gtkmathview/gtkmathview.h>
  31 #include "guiGTK.h"
  32
  33 #define XLINK_NS_URI "http://www.w3.org/1999/xlink"
  34
  35 static GtkWidget* window;
  36 static GtkWidget* main_area;
  37 static GtkWidget* scrolled_area;
  38 static GtkMenuItem* anti_aliasing_item;
  39 static GtkMenuItem* transparency_item;
  40
  41 static gpointer context = NULL;
  42 static gchar* doc_name = NULL;
  43 static GdomeElement* first_selected = NULL;
  44 static GdomeElement* root_selected = NULL;
  45
  46 static void create_widget_set(gpointer);
  47 static GtkWidget* get_main_menu(void);
  48 static void file_open(GtkWidget*, gpointer);
  49 static void file_re_open(GtkWidget*, gpointer);
  50 static void file_close(GtkWidget*, gpointer);
  51 static void file_output_tex(GtkWidget*, gpointer);
  52 static void options_font_manager(GtkWidget*, FontManagerId);
  53 static void options_set_font_size(GtkWidget*, gpointer);
  54 static void options_change_font_size(GtkWidget*, gboolean);
  55 static void options_verbosity(GtkWidget*, guint);
  56 static void options_anti_aliasing(GtkWidget*, gpointer);
  57 static void options_transparency(GtkWidget*, gpointer);
  58 static void edit_delete_selection(GtkWidget*, gpointer);
  59 static void edit_select_parent(GtkWidget*, gpointer);
  60 static void edit_reset_selection(GtkWidget*, gpointer);
  61 static void edit_reset(GtkWidget*, gpointer);
  62 static void edit_insert(GtkWidget*, gpointer);
  63 static void help_about(GtkWidget*, gpointer);
  64
  65 static GtkItemFactoryEntry menu_items[] = {
  66   { "/_File",                          NULL,         NULL,          0, "<Branch>" },
  67   { "/File/_Open...",                  "<control>O", file_open,     0, NULL },
  68   { "/File/_Reopen",                   NULL,         file_re_open,  0, NULL },
  69   { "/File/_Close",                    "<control>W", file_close,    0, NULL },
  70   { "/File/Output _TeX",               NULL,         file_output_tex, 0, NULL },
  71   { "/File/sep1",                      NULL,         NULL,          0, "<Separator>" },
  72   { "/File/_Quit",                     "<control>Q", gtk_main_quit, 0, NULL },
  73
  74   { "/_Edit",                          NULL, NULL,                  0,  "<Branch>" },
  75   { "/Edit/Reset Selection",           NULL, edit_reset_selection,  0, NULL },
  76   { "/Edit/Delete Selection",          NULL, edit_delete_selection, 0, NULL },
  77   { "/Edit/Select Parent",             NULL, edit_select_parent,    0, NULL },
  78   { "/Edit/sep1",                      NULL,         NULL,          0, "<Separator>" },
  79   { "/Edit/_Reset",                    NULL, edit_reset,            0, NULL },
  80   { "/Edit/Insert...",                 "<control>I", edit_insert,   0, NULL },
  81
  82   { "/_Options",                       NULL, NULL,                  0,  "<Branch>" },
  83   { "/Options/Default _Font Size",     NULL, NULL,                  0,  "<Branch>" },
  84   { "/Options/Default Font Size/Set...", NULL, options_set_font_size, 0,  NULL },
  85   { "/Options/Default Font Size/sep1", NULL, NULL,                  0,  "<Separator>" },
  86   { "/Options/Default Font Size/Larger", NULL, options_change_font_size, TRUE, NULL },
  87   { "/Options/Default Font Size/Smaller", NULL, options_change_font_size, FALSE, NULL },
  88   { "/Options/Font Manager",           NULL, NULL,                  0,  "<Branch>" },
  89   { "/Options/Font Manager/_GTK",      NULL, options_font_manager,  FONT_MANAGER_GTK, "<RadioItem>" },
  90   { "/Options/Font Manager/_Type 1",   NULL, options_font_manager,  FONT_MANAGER_T1, "/Options/Font Manager/GTK" },
  91   { "/Options/Verbosity",              NULL, NULL,                  0,  "<Branch>" },
  92   { "/Options/Verbosity/_Errors",      NULL, options_verbosity,     0,  "<RadioItem>" },
  93   { "/Options/Verbosity/_Warnings",    NULL, options_verbosity,     1,  "/Options/Verbosity/Errors" },
  94   { "/Options/Verbosity/_Info",        NULL, options_verbosity,     2,  "/Options/Verbosity/Errors" },
  95   { "/Options/Verbosity/_Debug",       NULL, options_verbosity,     3,  "/Options/Verbosity/Errors" },
  96   { "/Options/sep1",                   NULL, NULL,                  0,  "<Separator>" },
  97   { "/Options/_Anti Aliasing",         NULL, options_anti_aliasing, 0,  "<ToggleItem>" },
  98   { "/Options/_Transparency",          NULL, options_transparency,  0,  "<ToggleItem>" },
  99
 100   { "/_Help" ,        NULL,         NULL,          0, "<LastBranch>" },
 101   { "/Help/About...", NULL,         help_about,    0, NULL }
 102 };
 103
 104 static void
 105 quick_message(const char* msg)
 106 {
 107   GtkWidget* dialog;
 108   GtkWidget* label;
 109   GtkWidget* okay_button;
 110
 111   /* Create the widgets */
 112
 113   dialog = gtk_dialog_new();
 114   label = gtk_label_new (msg);
 115   okay_button = gtk_button_new_with_label("OK");
 116
 117   gtk_widget_set_usize(dialog, 300, 100);
 118
 119   /* Ensure that the dialog box is destroyed when the user clicks ok. */
 120
 121   gtk_signal_connect_object (GTK_OBJECT (okay_button), "clicked",
 122                              GTK_SIGNAL_FUNC (gtk_widget_destroy), dialog);
 123   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->action_area),
 124                      okay_button);
 125
 126   /* Add the label, and show everything we've added to the dialog. */
 127
 128   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox), label);
 129   gtk_widget_show_all (dialog);
 130 }
 131
 132 static void
 133 load_error_msg(const char* name)
 134 {
 135   char* msg = g_strdup_printf("Could not load\n`%s'", name);
 136   quick_message(msg);
 137   g_free(msg);
 138 }
 139
 140 static guint edit_timeout_id;
 141 extern void edit_timeout(gpointer);
 142
 143 void
 144 GUI_init(int* argc, char*** argv, char* title, guint width, guint height, gpointer c)
 145 {
 146   gtk_init(argc, argv);
 147
 148   window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
 149   gtk_window_set_title(GTK_WINDOW(window), title);
 150   gtk_window_set_default_size(GTK_WINDOW(window), width, height);
 151   gtk_signal_connect(GTK_OBJECT(window), "delete_event", (GtkSignalFunc) gtk_main_quit, NULL);
 152   create_widget_set(context);
 153
 154   gtk_widget_show(window);
 155
 156   context = c;
 157   /*edit_timeout_id = gtk_timeout_add(50, edit_timeout, context);*/
 158 }
 159
 160 void
 161 GUI_uninit()
 162 {
 163   GdomeException exc = 0;
 164
 165   if (first_selected != NULL)
 166     {
 167       gdome_el_unref(first_selected, &exc);
 168       g_assert(exc == 0);
 169       first_selected = NULL;
 170     }
 171
 172   if (root_selected != NULL)
 173     {
 174       gdome_el_unref(root_selected, &exc);
 175       g_assert(exc == 0);
 176       root_selected = NULL;
 177     }
 178
 179   context = NULL;
 180 }
 181
 182 int
 183 GUI_load_document(GdomeDocument* doc)
 184 {
 185   GtkMathView* math_view;
 186
 187   g_return_val_if_fail(doc != NULL, -1);
 188   g_return_val_if_fail(main_area != NULL, -1);
 189   g_return_val_if_fail(GTK_IS_MATH_VIEW(main_area), -1);
 190
 191   math_view = GTK_MATH_VIEW(main_area);
 192
 193   if (!gtk_math_view_load_doc(math_view, doc)) return -1;
 194
 195   return 0;
 196 }
 197
 198 void
 199 GUI_freeze()
 200 {
 201   gtk_math_view_freeze(GTK_MATH_VIEW(main_area));
 202 }
 203
 204 void
 205 GUI_thaw()
 206 {
 207   gtk_math_view_thaw(GTK_MATH_VIEW(main_area));
 208 }
 209
 210 void
 211 GUI_unload_document()
 212 {
 213   GtkMathView* math_view;
 214
 215   g_return_if_fail(main_area != NULL);
 216   g_return_if_fail(GTK_IS_MATH_VIEW(main_area));
 217
 218   math_view = GTK_MATH_VIEW(main_area);
 219
 220   gtk_math_view_unload(math_view);
 221
 222   if (doc_name != NULL) g_free(doc_name);
 223   doc_name = NULL;
 224 }
 225
 226 void
 227 GUI_run()
 228 {
 229   gtk_main();
 230 }
 231
 232 void
 233 GUI_set_font_manager(FontManagerId id)
 234 {
 235   gboolean t1;
 236   GtkMathView* math_view;
 237
 238   g_return_if_fail(id != FONT_MANAGER_UNKNOWN);
 239   g_return_if_fail(main_area != NULL);
 240   g_return_if_fail(GTK_IS_MATH_VIEW(main_area));
 241
 242   t1 = id == FONT_MANAGER_T1;
 243
 244   math_view = GTK_MATH_VIEW(main_area);
 245
 246   gtk_math_view_freeze(math_view);
 247
 248   if (id != gtk_math_view_get_font_manager_type(math_view))
 249     gtk_math_view_set_font_manager_type(math_view, id);
 250
 251   gtk_widget_set_sensitive(anti_aliasing_item, t1);
 252   gtk_widget_set_sensitive(transparency_item, t1);
 253
 254   if (t1)
 255     {
 256       gtk_math_view_set_anti_aliasing(math_view, GTK_CHECK_MENU_ITEM(anti_aliasing_item)->active);
 257       gtk_math_view_set_transparency(math_view, GTK_CHECK_MENU_ITEM(transparency_item)->active);
 258     }
 259
 260   gtk_math_view_thaw(math_view);
 261 }
 262
 263 static void
 264 store_filename(GtkFileSelection* selector, GtkWidget* user_data)
 265 {
 266   gchar* selected_filename = gtk_file_selection_get_filename (GTK_FILE_SELECTION(user_data));
 267   if (selected_filename != NULL)
 268     GUI_load_document(selected_filename);
 269 }
 270
 271 static void
 272 file_close(GtkWidget* widget, gpointer data)
 273 {
 274   GUI_unload_document();
 275 }
 276
 277 static void
 278 file_re_open(GtkWidget* widget, gpointer data)
 279 {
 280   if (doc_name != NULL) {
 281     GUI_load_document(doc_name);
 282   }
 283 }
 284
 285 static void
 286 file_open(GtkWidget* widget, gpointer data)
 287 {
 288   GtkWidget* fs = gtk_file_selection_new("Open File");
 289
 290   gtk_signal_connect (GTK_OBJECT (GTK_FILE_SELECTION(fs)->ok_button),
 291                       "clicked", GTK_SIGNAL_FUNC (store_filename), (gpointer) fs);
 292
 293   /* Ensure that the dialog box is destroyed when the user clicks a button. */
 294
 295   gtk_signal_connect_object (GTK_OBJECT (GTK_FILE_SELECTION(fs)->ok_button),
 296                              "clicked", GTK_SIGNAL_FUNC (gtk_widget_destroy),
 297                              (gpointer) fs);
 298
 299   gtk_signal_connect_object (GTK_OBJECT (GTK_FILE_SELECTION(fs)->cancel_button),
 300                              "clicked", GTK_SIGNAL_FUNC (gtk_widget_destroy),
 301                              (gpointer) fs);
 302
 303   /* Display that dialog */
 304
 305   gtk_widget_show (fs);
 306 }
 307
 308 static void
 309 file_output_tex(GtkWidget* widget, gpointer data)
 310 {
 311   g_assert(context != NULL);
 312   edit_output_tex(context);
 313 }
 314
 315 static void
 316 options_font_manager(GtkWidget* widget, FontManagerId id)
 317 {
 318   g_return_if_fail(id != FONT_MANAGER_UNKNOWN);
 319   GUI_set_font_manager(id);
 320 }
 321
 322 static void
 323 options_anti_aliasing(GtkWidget* widget, gpointer data)
 324 {
 325   gboolean aa = gtk_math_view_get_anti_aliasing(GTK_MATH_VIEW(main_area));
 326   gtk_math_view_set_anti_aliasing(GTK_MATH_VIEW(main_area), !aa);
 327 }
 328
 329 static void
 330 options_transparency(GtkWidget* widget, gpointer data)
 331 {
 332   gboolean t = gtk_math_view_get_transparency(GTK_MATH_VIEW(main_area));
 333   gtk_math_view_set_transparency(GTK_MATH_VIEW(main_area), !t);
 334 }
 335
 336 static void
 337 options_verbosity(GtkWidget* widget, guint level)
 338 {
 339   gtk_math_view_set_log_verbosity(GTK_MATH_VIEW(main_area), level);
 340 }
 341
 342 static void
 343 edit_delete_selection(GtkWidget* widget, gpointer data)
 344 {
 345   if (root_selected != NULL)
 346     {
 347       GdomeException exc;
 348       gtk_math_view_freeze(GTK_MATH_VIEW(main_area));
 349       printf("about to remove element %p\n", root_selected);
 350       delete_element(root_selected);
 351       gdome_el_unref(root_selected, &exc);
 352       g_assert(exc == 0);
 353       root_selected = NULL;
 354       gtk_math_view_thaw(GTK_MATH_VIEW(main_area));
 355     }
 356 }
 357
 358 static void
 359 edit_select_parent(GtkWidget* widget, gpointer data)
 360 {
 361   if (root_selected != NULL)
 362     {
 363       GdomeException exc = 0;
 364       GdomeElement* parent = gdome_n_parentNode(root_selected, &exc);
 365       g_assert(exc == 0);
 366       gdome_el_unref(root_selected, &exc);
 367       g_assert(exc == 0);
 368       root_selected = parent;
 369       /* gtk_math_view_set_selection(GTK_MATH_VIEW(main_area), root_selected); */
 370     }
 371 }
 372
 373 static void
 374 edit_reset_selection(GtkWidget* widget, gpointer data)
 375 {
 376   if (root_selected != NULL)
 377     {
 378       GdomeException exc = 0;
 379       /* gtk_math_view_reset_selection(GTK_MATH_VIEW(main_area), root_selected); */
 380       gdome_el_unref(root_selected, &exc);
 381       g_assert(exc == 0);
 382       root_selected = NULL;
 383     }
 384 }
 385
 386 static void
 387 edit_reset(GtkWidget* widget, gpointer data)
 388 {
 389   g_assert(context != NULL);
 390   edit_reset_tex(context);
 391 }
 392
 393 static void
 394 insert_tex(GtkWidget* widget, GtkEntry* entry)
 395 {
 396   gchar* text;
 397   g_return_if_fail(entry != NULL);
 398
 399   text = gtk_editable_get_chars(GTK_EDITABLE(entry), 0, -1);
 400   edit_push_string(context, text);
 401   g_free(text);
 402 }
 403
 404 static void
 405 edit_insert(GtkWidget* widget, gpointer data)
 406 {
 407   GtkWidget* dialog;
 408   GtkWidget* entry;
 409   GtkWidget* ok;
 410   GtkWidget* cancel;
 411
 412   dialog = gtk_dialog_new();
 413   entry = gtk_entry_new();
 414   ok = gtk_button_new_with_label("OK");
 415   cancel = gtk_button_new_with_label("Cancel");
 416
 417   gtk_signal_connect (GTK_OBJECT (ok), "clicked",
 418                       GTK_SIGNAL_FUNC (insert_tex), (gpointer) entry);
 419
 420   gtk_signal_connect_object (GTK_OBJECT (ok), "clicked",
 421                              GTK_SIGNAL_FUNC (gtk_widget_destroy), (gpointer) dialog);
 422
 423   gtk_signal_connect_object (GTK_OBJECT (ok), "clicked",
 424                              GTK_SIGNAL_FUNC (gtk_widget_destroy), (gpointer) dialog);
 425
 426   gtk_signal_connect_object (GTK_OBJECT (cancel), "clicked",
 427                              GTK_SIGNAL_FUNC (gtk_widget_destroy), (gpointer) dialog);
 428
 429   gtk_container_set_border_width (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox), 5);
 430
 431   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox), entry);
 432   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->action_area), ok);
 433   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->action_area), cancel);
 434
 435   gtk_widget_show_all (dialog);
 436 }
 437
 438 static void
 439 help_about(GtkWidget* widget, gpointer data)
 440 {
 441   GtkWidget* dialog;
 442   GtkWidget* label;
 443   GtkWidget* ok;
 444
 445   dialog = gtk_dialog_new();
 446   label = gtk_label_new("\n    MathML Editor    \n    Copyright (C) 2003 Luca Padovani    \n");
 447   ok = gtk_button_new_with_label("Close");
 448
 449   gtk_signal_connect_object (GTK_OBJECT (ok), "clicked",
 450                              GTK_SIGNAL_FUNC (gtk_widget_destroy), (gpointer) dialog);
 451   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->action_area),
 452                      ok);
 453
 454   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox), label);
 455
 456   gtk_widget_show_all (dialog);
 457 }
 458
 459 static void
 460 change_default_font_size(GtkWidget* widget, GtkSpinButton* spin)
 461 {
 462   g_return_if_fail(spin != NULL);
 463   gtk_math_view_set_font_size( GTK_MATH_VIEW(main_area), gtk_spin_button_get_value_as_int(spin));
 464 }
 465
 466 static void
 467 options_change_font_size(GtkWidget* widget, gboolean larger)
 468 {
 469   gfloat size = gtk_math_view_get_font_size (GTK_MATH_VIEW(main_area));
 470   if (larger) size = size / 0.71;
 471   else size = size * 0.71;
 472   if (size < 1) size = 1;
 473   gtk_math_view_set_font_size (GTK_MATH_VIEW(main_area), (gint) size + 0.5);
 474 }
 475
 476 static void
 477 options_set_font_size(GtkWidget* widget, gpointer data)
 478 {
 479   GtkWidget* dialog;
 480   GtkWidget* label;
 481   GtkWidget* ok;
 482   GtkWidget* cancel;
 483   GtkWidget* spin;
 484   GtkObject* adj;
 485
 486   dialog = gtk_dialog_new();
 487   label = gtk_label_new("Default font size:");
 488   ok = gtk_button_new_with_label("OK");
 489   cancel = gtk_button_new_with_label("Cancel");
 490
 491   adj = gtk_adjustment_new (gtk_math_view_get_font_size (GTK_MATH_VIEW(main_area)), 1, 200, 1, 1, 1);
 492   spin = gtk_spin_button_new (GTK_ADJUSTMENT(adj), 1, 0);
 493   gtk_spin_button_set_numeric (GTK_SPIN_BUTTON (spin), TRUE);
 494
 495   gtk_signal_connect (GTK_OBJECT (ok), "clicked",
 496                       GTK_SIGNAL_FUNC (change_default_font_size), (gpointer) spin);
 497
 498   gtk_signal_connect_object (GTK_OBJECT (ok), "clicked",
 499                              GTK_SIGNAL_FUNC (gtk_widget_destroy), (gpointer) dialog);
 500
 501   gtk_signal_connect_object (GTK_OBJECT (ok), "clicked",
 502                              GTK_SIGNAL_FUNC (gtk_widget_destroy), (gpointer) dialog);
 503
 504   gtk_signal_connect_object (GTK_OBJECT (cancel), "clicked",
 505                              GTK_SIGNAL_FUNC (gtk_widget_destroy), (gpointer) dialog);
 506
 507   gtk_container_set_border_width (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox), 5);
 508
 509   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->action_area), ok);
 510   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->action_area), cancel);
 511   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox), label);
 512   gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox), spin);
 513
 514   gtk_widget_show_all (dialog);
 515 }
 516
 517 static void
 518 select_begin(GtkMathView* math_view, GdomeElement* first, gint state)
 519 {
 520   GdomeException exc = 0;
 521
 522   g_return_if_fail(math_view != NULL);
 523   g_return_if_fail(GTK_IS_MATH_VIEW(math_view));
 524   g_return_if_fail(first != NULL);
 525
 526   gtk_math_view_freeze(math_view);
 527
 528   if (root_selected != NULL)
 529     {
 530       gtk_math_view_unselect(math_view, root_selected);
 531       gdome_el_unref(root_selected, &exc);
 532       g_assert(exc == 0);
 533     }
 534
 535   root_selected = first_selected = find_element_with_ref(first);
 536
 537   if (root_selected != NULL)
 538     {
 539       gtk_math_view_select(math_view, root_selected);
 540       gdome_el_ref(root_selected, &exc);
 541       g_assert(exc == 0);
 542     }
 543
 544   gtk_math_view_thaw(math_view);
 545 }
 546
 547 static void
 548 select_over(GtkMathView* math_view, GdomeElement* elem, gint state)
 549 {
 550   GdomeElement* new_selected = NULL;
 551   GdomeException exc = 0;
 552
 553   g_return_if_fail(math_view != NULL);
 554   g_return_if_fail(GTK_IS_MATH_VIEW(math_view));
 555   g_return_if_fail(elem != NULL);
 556
 557   if (first_selected == NULL || elem == NULL)
 558     new_selected = NULL;
 559   else
 560     new_selected = find_common_ancestor_with_ref(first_selected, elem);
 561
 562   if (new_selected != root_selected)
 563     {
 564       gtk_math_view_freeze(math_view);
 565       if (root_selected != NULL)
 566         {
 567           gtk_math_view_unselect(math_view, root_selected);
 568           gdome_el_unref(root_selected, &exc);
 569           g_assert(exc == 0);
 570         }
 571       root_selected = new_selected;
 572       if (root_selected != NULL)
 573         gtk_math_view_select(math_view, root_selected);
 574       gtk_math_view_thaw(math_view);
 575     }
 576   else if (new_selected != NULL)
 577     {
 578       gdome_el_unref(new_selected, &exc);
 579       g_assert(exc == 0);
 580     }
 581
 582 }
 583
 584 static gboolean
 585 key_press_event(gpointer c,
 586                 GdkEventKey* event,
 587                 GtkWidget* widget)
 588 {
 589   g_return_val_if_fail(widget != NULL, FALSE);
 590   g_return_val_if_fail(event != NULL, FALSE);
 591   g_return_val_if_fail(context != NULL, FALSE);
 592
 593   if (event->type != GDK_KEY_PRESS) return FALSE;
 594
 595   switch (event->keyval)
 596     {
 597     case GDK_BackSpace:
 598       edit_drop(context, event->state & GDK_MOD1_MASK);
 599       break;
 600     default:
 601       if ((event->state & (~GDK_SHIFT_MASK)) == 0 && event->keyval < 0x80)
 602         edit_push_char(context, event->keyval);
 603       return FALSE;
 604     }
 605
 606   return TRUE;
 607 }
 608
 609 static void
 610 create_widget_set(gpointer context)
 611 {
 612   GtkWidget* main_vbox;
 613   GtkWidget* menu_bar;
 614
 615   main_vbox = gtk_vbox_new(FALSE, 1);
 616   gtk_container_border_width(GTK_CONTAINER(main_vbox), 1);
 617   gtk_container_add(GTK_CONTAINER(window), main_vbox);
 618   gtk_widget_show(main_vbox);
 619
 620   menu_bar = get_main_menu();
 621   gtk_box_pack_start(GTK_BOX(main_vbox), menu_bar, FALSE, TRUE, 0);
 622   gtk_widget_show(menu_bar);
 623
 624   main_area = gtk_math_view_new(NULL, NULL);
 625   gtk_widget_show(main_area);
 626
 627   //gtk_math_view_set_log_verbosity(GTK_MATH_VIEW(main_area), 3);
 628
 629   gtk_signal_connect_object (GTK_OBJECT (main_area),
 630                              "select_begin", GTK_SIGNAL_FUNC (select_begin),
 631                              (gpointer) main_area);
 632
 633   gtk_signal_connect_object (GTK_OBJECT (main_area),
 634                              "select_over", GTK_SIGNAL_FUNC (select_over),
 635                              (gpointer) main_area);
 636
 637   gtk_signal_connect_object (GTK_OBJECT(window),
 638                              "key_press_event", GTK_SIGNAL_FUNC(key_press_event),
 639                              context);
 640
 641   gtk_widget_add_events(GTK_WIDGET(main_area), GDK_KEY_PRESS_MASK);
 642
 643   scrolled_area = gtk_scrolled_window_new(NULL, NULL);
 644   gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(scrolled_area),
 645                                  GTK_POLICY_AUTOMATIC, GTK_POLICY_ALWAYS);
 646
 647   gtk_widget_show(scrolled_area);
 648   gtk_container_add(GTK_CONTAINER(scrolled_area), main_area);
 649   gtk_box_pack_start(GTK_BOX(main_vbox), scrolled_area, TRUE, TRUE, 0);
 650
 651   gtk_widget_show(main_vbox);
 652
 653   if (gtk_math_view_get_anti_aliasing(GTK_MATH_VIEW(main_area)))
 654     gtk_menu_item_activate(anti_aliasing_item);
 655 }
 656
 657 GtkWidget*
 658 get_main_menu()
 659 {
 660   GtkItemFactory* item_factory;
 661   GtkAccelGroup* accel_group;
 662   GtkWidget* menu_item;
 663
 664   gint nmenu_items = sizeof(menu_items) / sizeof(menu_items[0]);
 665
 666   accel_group = gtk_accel_group_new();
 667
 668   item_factory = gtk_item_factory_new(GTK_TYPE_MENU_BAR, "<main>", accel_group);
 669
 670   gtk_item_factory_create_items(item_factory, nmenu_items, menu_items, NULL);
 671
 672   gtk_window_add_accel_group(GTK_WINDOW(window), accel_group);
 673
 674   menu_item = gtk_item_factory_get_widget(item_factory, "/Options/Anti Aliasing");
 675   anti_aliasing_item = GTK_MENU_ITEM(menu_item);
 676
 677   menu_item = gtk_item_factory_get_widget(item_factory, "/Options/Transparency");
 678   transparency_item = GTK_MENU_ITEM(menu_item);
 679
 680   return gtk_item_factory_get_widget(item_factory, "<main>");
 681 }