Pileus Git - ~andy/gtk/blob - gtk/gtkadjustment.c

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GTK+ Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 #include "config.h"
  28 #include "gtkadjustment.h"
  29 #include "gtkmarshalers.h"
  30 #include "gtkprivate.h"
  31 #include "gtkintl.h"
  32
  33
  34 enum
  35 {
  36   PROP_0,
  37   PROP_VALUE,
  38   PROP_LOWER,
  39   PROP_UPPER,
  40   PROP_STEP_INCREMENT,
  41   PROP_PAGE_INCREMENT,
  42   PROP_PAGE_SIZE
  43 };
  44
  45 enum
  46 {
  47   CHANGED,
  48   VALUE_CHANGED,
  49   LAST_SIGNAL
  50 };
  51
  52
  53 static void gtk_adjustment_get_property                (GObject      *object,
  54                                                         guint         prop_id,
  55                                                         GValue       *value,
  56                                                         GParamSpec   *pspec);
  57 static void gtk_adjustment_set_property                (GObject      *object,
  58                                                         guint         prop_id,
  59                                                         const GValue *value,
  60                                                         GParamSpec   *pspec);
  61 static void gtk_adjustment_dispatch_properties_changed (GObject      *object,
  62                                                         guint         n_pspecs,
  63                                                         GParamSpec  **pspecs);
  64
  65 static guint adjustment_signals[LAST_SIGNAL] = { 0 };
  66
  67 static guint64 adjustment_changed_stamp = 0; /* protected by global gdk lock */
  68
  69 G_DEFINE_TYPE (GtkAdjustment, gtk_adjustment, G_TYPE_INITIALLY_UNOWNED)
  70
  71 static void
  72 gtk_adjustment_class_init (GtkAdjustmentClass *class)
  73 {
  74   GObjectClass *gobject_class = G_OBJECT_CLASS (class);
  75
  76   gobject_class->set_property                = gtk_adjustment_set_property;
  77   gobject_class->get_property                = gtk_adjustment_get_property;
  78   gobject_class->dispatch_properties_changed = gtk_adjustment_dispatch_properties_changed;
  79
  80   class->changed = NULL;
  81   class->value_changed = NULL;
  82
  83   /**
  84    * GtkAdjustment:value:
  85    *
  86    * The value of the adjustment.
  87    *
  88    * Since: 2.4
  89    */
  90   g_object_class_install_property (gobject_class,
  91                                    PROP_VALUE,
  92                                    g_param_spec_double ("value",
  93                                                         P_("Value"),
  94                                                         P_("The value of the adjustment"),
  95                                                         -G_MAXDOUBLE,
  96                                                         G_MAXDOUBLE,
  97                                                         0.0,
  98                                                         GTK_PARAM_READWRITE));
  99
 100   /**
 101    * GtkAdjustment:lower:
 102    *
 103    * The minimum value of the adjustment.
 104    *
 105    * Since: 2.4
 106    */
 107   g_object_class_install_property (gobject_class,
 108                                    PROP_LOWER,
 109                                    g_param_spec_double ("lower",
 110                                                         P_("Minimum Value"),
 111                                                         P_("The minimum value of the adjustment"),
 112                                                         -G_MAXDOUBLE,
 113                                                         G_MAXDOUBLE,
 114                                                         0.0,
 115                                                         GTK_PARAM_READWRITE));
 116
 117   /**
 118    * GtkAdjustment:upper:
 119    *
 120    * The maximum value of the adjustment.
 121    * Note that values will be restricted by
 122    * <literal>upper - page-size</literal> if the page-size
 123    * property is nonzero.
 124    *
 125    * Since: 2.4
 126    */
 127   g_object_class_install_property (gobject_class,
 128                                    PROP_UPPER,
 129                                    g_param_spec_double ("upper",
 130                                                         P_("Maximum Value"),
 131                                                         P_("The maximum value of the adjustment"),
 132                                                         -G_MAXDOUBLE,
 133                                                         G_MAXDOUBLE,
 134                                                         0.0,
 135                                                         GTK_PARAM_READWRITE));
 136
 137   /**
 138    * GtkAdjustment:step-increment:
 139    *
 140    * The step increment of the adjustment.
 141    *
 142    * Since: 2.4
 143    */
 144   g_object_class_install_property (gobject_class,
 145                                    PROP_STEP_INCREMENT,
 146                                    g_param_spec_double ("step-increment",
 147                                                         P_("Step Increment"),
 148                                                         P_("The step increment of the adjustment"),
 149                                                         -G_MAXDOUBLE,
 150                                                         G_MAXDOUBLE,
 151                                                         0.0,
 152                                                         GTK_PARAM_READWRITE));
 153
 154   /**
 155    * GtkAdjustment:page-increment:
 156    *
 157    * The page increment of the adjustment.
 158    *
 159    * Since: 2.4
 160    */
 161   g_object_class_install_property (gobject_class,
 162                                    PROP_PAGE_INCREMENT,
 163                                    g_param_spec_double ("page-increment",
 164                                                         P_("Page Increment"),
 165                                                         P_("The page increment of the adjustment"),
 166                                                         -G_MAXDOUBLE,
 167                                                         G_MAXDOUBLE,
 168                                                         0.0,
 169                                                         GTK_PARAM_READWRITE));
 170
 171   /**
 172    * GtkAdjustment:page-size:
 173    *
 174    * The page size of the adjustment.
 175    * Note that the page-size is irrelevant and should be set to zero
 176    * if the adjustment is used for a simple scalar value, e.g. in a
 177    * #GtkSpinButton.
 178    *
 179    * Since: 2.4
 180    */
 181   g_object_class_install_property (gobject_class,
 182                                    PROP_PAGE_SIZE,
 183                                    g_param_spec_double ("page-size",
 184                                                         P_("Page Size"),
 185                                                         P_("The page size of the adjustment"),
 186                                                         -G_MAXDOUBLE,
 187                                                         G_MAXDOUBLE,
 188                                                         0.0,
 189                                                         GTK_PARAM_READWRITE));
 190
 191   adjustment_signals[CHANGED] =
 192     g_signal_new (I_("changed"),
 193                   G_OBJECT_CLASS_TYPE (class),
 194                   G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE,
 195                   G_STRUCT_OFFSET (GtkAdjustmentClass, changed),
 196                   NULL, NULL,
 197                   _gtk_marshal_VOID__VOID,
 198                   G_TYPE_NONE, 0);
 199
 200   adjustment_signals[VALUE_CHANGED] =
 201     g_signal_new (I_("value-changed"),
 202                   G_OBJECT_CLASS_TYPE (class),
 203                   G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE,
 204                   G_STRUCT_OFFSET (GtkAdjustmentClass, value_changed),
 205                   NULL, NULL,
 206                   _gtk_marshal_VOID__VOID,
 207                   G_TYPE_NONE, 0);
 208 }
 209
 210 static void
 211 gtk_adjustment_init (GtkAdjustment *adjustment)
 212 {
 213   adjustment->value = 0.0;
 214   adjustment->lower = 0.0;
 215   adjustment->upper = 0.0;
 216   adjustment->step_increment = 0.0;
 217   adjustment->page_increment = 0.0;
 218   adjustment->page_size = 0.0;
 219 }
 220
 221 static void
 222 gtk_adjustment_get_property (GObject    *object,
 223                              guint       prop_id,
 224                              GValue     *value,
 225                              GParamSpec *pspec)
 226 {
 227   GtkAdjustment *adjustment = GTK_ADJUSTMENT (object);
 228
 229   switch (prop_id)
 230     {
 231     case PROP_VALUE:
 232       g_value_set_double (value, adjustment->value);
 233       break;
 234     case PROP_LOWER:
 235       g_value_set_double (value, adjustment->lower);
 236       break;
 237     case PROP_UPPER:
 238       g_value_set_double (value, adjustment->upper);
 239       break;
 240     case PROP_STEP_INCREMENT:
 241       g_value_set_double (value, adjustment->step_increment);
 242       break;
 243     case PROP_PAGE_INCREMENT:
 244       g_value_set_double (value, adjustment->page_increment);
 245       break;
 246     case PROP_PAGE_SIZE:
 247       g_value_set_double (value, adjustment->page_size);
 248       break;
 249     default:
 250       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 251       break;
 252     }
 253 }
 254
 255 static void
 256 gtk_adjustment_set_property (GObject      *object,
 257                              guint         prop_id,
 258                              const GValue *value,
 259                              GParamSpec   *pspec)
 260 {
 261   GtkAdjustment *adjustment = GTK_ADJUSTMENT (object);
 262   gdouble double_value = g_value_get_double (value);
 263
 264   switch (prop_id)
 265     {
 266     case PROP_VALUE:
 267       gtk_adjustment_set_value (adjustment, double_value);
 268       break;
 269     case PROP_LOWER:
 270       adjustment->lower = double_value;
 271       break;
 272     case PROP_UPPER:
 273       adjustment->upper = double_value;
 274       break;
 275     case PROP_STEP_INCREMENT:
 276       adjustment->step_increment = double_value;
 277       break;
 278     case PROP_PAGE_INCREMENT:
 279       adjustment->page_increment = double_value;
 280       break;
 281     case PROP_PAGE_SIZE:
 282       adjustment->page_size = double_value;
 283       break;
 284     default:
 285       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 286       break;
 287     }
 288 }
 289
 290 static void
 291 gtk_adjustment_dispatch_properties_changed (GObject     *object,
 292                                             guint        n_pspecs,
 293                                             GParamSpec **pspecs)
 294 {
 295   gboolean changed = FALSE;
 296   gint i;
 297
 298   G_OBJECT_CLASS (gtk_adjustment_parent_class)->dispatch_properties_changed (object, n_pspecs, pspecs);
 299
 300   for (i = 0; i < n_pspecs; i++)
 301     switch (pspecs[i]->param_id)
 302       {
 303       case PROP_LOWER:
 304       case PROP_UPPER:
 305       case PROP_STEP_INCREMENT:
 306       case PROP_PAGE_INCREMENT:
 307       case PROP_PAGE_SIZE:
 308         changed = TRUE;
 309         break;
 310       default:
 311         break;
 312       }
 313
 314   if (changed)
 315     {
 316       adjustment_changed_stamp++;
 317       gtk_adjustment_changed (GTK_ADJUSTMENT (object));
 318     }
 319 }
 320
 321 GObject *
 322 gtk_adjustment_new (gdouble value,
 323                     gdouble lower,
 324                     gdouble upper,
 325                     gdouble step_increment,
 326                     gdouble page_increment,
 327                     gdouble page_size)
 328 {
 329   return g_object_new (GTK_TYPE_ADJUSTMENT,
 330                        "lower", lower,
 331                        "upper", upper,
 332                        "step-increment", step_increment,
 333                        "page-increment", page_increment,
 334                        "page-size", page_size,
 335                        "value", value,
 336                        NULL);
 337 }
 338
 339 /**
 340  * gtk_adjustment_get_value:
 341  * @adjustment: a #GtkAdjustment
 342  *
 343  * Gets the current value of the adjustment. See
 344  * gtk_adjustment_set_value ().
 345  *
 346  * Return value: The current value of the adjustment.
 347  **/
 348 gdouble
 349 gtk_adjustment_get_value (GtkAdjustment *adjustment)
 350 {
 351   g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
 352
 353   return adjustment->value;
 354 }
 355
 356 void
 357 gtk_adjustment_set_value (GtkAdjustment *adjustment,
 358                           gdouble        value)
 359 {
 360   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 361
 362   /* don't use CLAMP() so we don't end up below lower if upper - page_size
 363    * is smaller than lower
 364    */
 365   value = MIN (value, adjustment->upper - adjustment->page_size);
 366   value = MAX (value, adjustment->lower);
 367
 368   if (value != adjustment->value)
 369     {
 370       adjustment->value = value;
 371
 372       gtk_adjustment_value_changed (adjustment);
 373     }
 374 }
 375
 376 /**
 377  * gtk_adjustment_get_lower:
 378  * @adjustment: a #GtkAdjustment
 379  *
 380  * Retrieves the minimum value of the adjustment.
 381  *
 382  * Return value: The current minimum value of the adjustment.
 383  *
 384  * Since: 2.14
 385  **/
 386 gdouble
 387 gtk_adjustment_get_lower (GtkAdjustment *adjustment)
 388 {
 389   g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
 390
 391   return adjustment->lower;
 392 }
 393
 394 /**
 395  * gtk_adjustment_set_lower:
 396  * @adjustment: a #GtkAdjustment
 397  * @lower: the new minimum value
 398  *
 399  * Sets the minimum value of the adjustment.
 400  *
 401  * When setting multiple adjustment properties via their individual
 402  * setters, multiple "changed" signals will be emitted. However, since
 403  * the emission of the "changed" signal is tied to the emission of the
 404  * "GObject::notify" signals of the changed properties, it's possible
 405  * to compress the "changed" signals into one by calling
 406  * g_object_freeze_notify() and g_object_thaw_notify() around the
 407  * calls to the individual setters.
 408  *
 409  * Alternatively, using a single g_object_set() for all the properties
 410  * to change, or using gtk_adjustment_configure() has the same effect
 411  * of compressing "changed" emissions.
 412  *
 413  * Since: 2.14
 414  **/
 415 void
 416 gtk_adjustment_set_lower (GtkAdjustment *adjustment,
 417                           gdouble        lower)
 418 {
 419   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 420
 421   if (lower != adjustment->lower)
 422     g_object_set (adjustment, "lower", lower, NULL);
 423 }
 424
 425 /**
 426  * gtk_adjustment_get_upper:
 427  * @adjustment: a #GtkAdjustment
 428  *
 429  * Retrieves the maximum value of the adjustment.
 430  *
 431  * Return value: The current maximum value of the adjustment.
 432  *
 433  * Since: 2.14
 434  **/
 435 gdouble
 436 gtk_adjustment_get_upper (GtkAdjustment *adjustment)
 437 {
 438   g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
 439
 440   return adjustment->upper;
 441 }
 442
 443 /**
 444  * gtk_adjustment_set_upper:
 445  * @adjustment: a #GtkAdjustment
 446  * @upper: the new maximum value
 447  *
 448  * Sets the maximum value of the adjustment.
 449  *
 450  * Note that values will be restricted by
 451  * <literal>upper - page-size</literal> if the page-size
 452  * property is nonzero.
 453  *
 454  * See gtk_adjustment_set_lower() about how to compress multiple
 455  * emissions of the "changed" signal when setting multiple adjustment
 456  * properties.
 457  *
 458  * Since: 2.14
 459  **/
 460 void
 461 gtk_adjustment_set_upper (GtkAdjustment *adjustment,
 462                           gdouble        upper)
 463 {
 464   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 465
 466   if (upper != adjustment->upper)
 467     g_object_set (adjustment, "upper", upper, NULL);
 468 }
 469
 470 /**
 471  * gtk_adjustment_get_step_increment:
 472  * @adjustment: a #GtkAdjustment
 473  *
 474  * Retrieves the step increment of the adjustment.
 475  *
 476  * Return value: The current step increment of the adjustment.
 477  *
 478  * Since: 2.14
 479  **/
 480 gdouble
 481 gtk_adjustment_get_step_increment (GtkAdjustment *adjustment)
 482 {
 483   g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
 484
 485   return adjustment->step_increment;
 486 }
 487
 488 /**
 489  * gtk_adjustment_set_step_increment:
 490  * @adjustment: a #GtkAdjustment
 491  * @step_increment: the new step increment
 492  *
 493  * Sets the step increment of the adjustment.
 494  *
 495  * See gtk_adjustment_set_lower() about how to compress multiple
 496  * emissions of the "changed" signal when setting multiple adjustment
 497  * properties.
 498  *
 499  * Since: 2.14
 500  **/
 501 void
 502 gtk_adjustment_set_step_increment (GtkAdjustment *adjustment,
 503                                    gdouble        step_increment)
 504 {
 505   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 506
 507   if (step_increment != adjustment->step_increment)
 508     g_object_set (adjustment, "step-increment", step_increment, NULL);
 509 }
 510
 511 /**
 512  * gtk_adjustment_get_page_increment:
 513  * @adjustment: a #GtkAdjustment
 514  *
 515  * Retrieves the page increment of the adjustment.
 516  *
 517  * Return value: The current page increment of the adjustment.
 518  *
 519  * Since: 2.14
 520  **/
 521 gdouble
 522 gtk_adjustment_get_page_increment (GtkAdjustment *adjustment)
 523 {
 524   g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
 525
 526   return adjustment->page_increment;
 527 }
 528
 529 /**
 530  * gtk_adjustment_set_page_increment:
 531  * @adjustment: a #GtkAdjustment
 532  * @page_increment: the new page increment
 533  *
 534  * Sets the page increment of the adjustment.
 535  *
 536  * See gtk_adjustment_set_lower() about how to compress multiple
 537  * emissions of the "changed" signal when setting multiple adjustment
 538  * properties.
 539  *
 540  * Since: 2.14
 541  **/
 542 void
 543 gtk_adjustment_set_page_increment (GtkAdjustment *adjustment,
 544                                    gdouble        page_increment)
 545 {
 546   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 547
 548   if (page_increment != adjustment->page_increment)
 549     g_object_set (adjustment, "page-increment", page_increment, NULL);
 550 }
 551
 552 /**
 553  * gtk_adjustment_get_page_size:
 554  * @adjustment: a #GtkAdjustment
 555  *
 556  * Retrieves the page size of the adjustment.
 557  *
 558  * Return value: The current page size of the adjustment.
 559  *
 560  * Since: 2.14
 561  **/
 562 gdouble
 563 gtk_adjustment_get_page_size (GtkAdjustment *adjustment)
 564 {
 565   g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
 566
 567   return adjustment->page_size;
 568 }
 569
 570 /**
 571  * gtk_adjustment_set_page_size:
 572  * @adjustment: a #GtkAdjustment
 573  * @page_size: the new page size
 574  *
 575  * Sets the page size of the adjustment.
 576  *
 577  * See gtk_adjustment_set_lower() about how to compress multiple
 578  * emissions of the "changed" signal when setting multiple adjustment
 579  * properties.
 580  *
 581  * Since: 2.14
 582  **/
 583 void
 584 gtk_adjustment_set_page_size (GtkAdjustment *adjustment,
 585                               gdouble        page_size)
 586 {
 587   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 588
 589   if (page_size != adjustment->page_size)
 590     g_object_set (adjustment, "page-size", page_size, NULL);
 591 }
 592
 593 /**
 594  * gtk_adjustment_configure:
 595  * @adjustment: a #GtkAdjustment
 596  * @value: the new value
 597  * @lower: the new minimum value
 598  * @upper: the new maximum value
 599  * @step_increment: the new step increment
 600  * @page_increment: the new page increment
 601  * @page_size: the new page size
 602  *
 603  * Sets all properties of the adjustment at once.
 604  *
 605  * Use this function to avoid multiple emissions of the "changed"
 606  * signal. See gtk_adjustment_set_lower() for an alternative way
 607  * of compressing multiple emissions of "changed" into one.
 608  *
 609  * Since: 2.14
 610  **/
 611 void
 612 gtk_adjustment_configure (GtkAdjustment *adjustment,
 613                           gdouble        value,
 614                           gdouble        lower,
 615                           gdouble        upper,
 616                           gdouble        step_increment,
 617                           gdouble        page_increment,
 618                           gdouble        page_size)
 619 {
 620   gboolean value_changed = FALSE;
 621   guint64 old_stamp = adjustment_changed_stamp;
 622
 623   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 624
 625   g_object_freeze_notify (G_OBJECT (adjustment));
 626
 627   g_object_set (adjustment,
 628                 "lower", lower,
 629                 "upper", upper,
 630                 "step-increment", step_increment,
 631                 "page-increment", page_increment,
 632                 "page-size", page_size,
 633                 NULL);
 634
 635   /* don't use CLAMP() so we don't end up below lower if upper - page_size
 636    * is smaller than lower
 637    */
 638   value = MIN (value, upper - page_size);
 639   value = MAX (value, lower);
 640
 641   if (value != adjustment->value)
 642     {
 643       /* set value manually to make sure "changed" is emitted with the
 644        * new value in place and is emitted before "value-changed"
 645        */
 646       adjustment->value = value;
 647       value_changed = TRUE;
 648     }
 649
 650   g_object_thaw_notify (G_OBJECT (adjustment));
 651
 652   if (old_stamp == adjustment_changed_stamp)
 653     gtk_adjustment_changed (adjustment); /* force emission before ::value-changed */
 654
 655   if (value_changed)
 656     gtk_adjustment_value_changed (adjustment);
 657 }
 658
 659 void
 660 gtk_adjustment_changed (GtkAdjustment *adjustment)
 661 {
 662   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 663
 664   g_signal_emit (adjustment, adjustment_signals[CHANGED], 0);
 665 }
 666
 667 void
 668 gtk_adjustment_value_changed (GtkAdjustment *adjustment)
 669 {
 670   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 671
 672   g_signal_emit (adjustment, adjustment_signals[VALUE_CHANGED], 0);
 673   g_object_notify (G_OBJECT (adjustment), "value");
 674 }
 675
 676 void
 677 gtk_adjustment_clamp_page (GtkAdjustment *adjustment,
 678                            gdouble        lower,
 679                            gdouble        upper)
 680 {
 681   gboolean need_emission;
 682
 683   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 684
 685   lower = CLAMP (lower, adjustment->lower, adjustment->upper);
 686   upper = CLAMP (upper, adjustment->lower, adjustment->upper);
 687
 688   need_emission = FALSE;
 689
 690   if (adjustment->value + adjustment->page_size < upper)
 691     {
 692       adjustment->value = upper - adjustment->page_size;
 693       need_emission = TRUE;
 694     }
 695   if (adjustment->value > lower)
 696     {
 697       adjustment->value = lower;
 698       need_emission = TRUE;
 699     }
 700
 701   if (need_emission)
 702     gtk_adjustment_value_changed (adjustment);
 703 }