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

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
   3  * Copyright (C) 2001 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22  * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
  23  * file for a list of people on the GTK+ Team.  See the ChangeLog
  24  * files for a list of changes.  These files are distributed with
  25  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  26  */
  27
  28 #include "config.h"
  29
  30 #include "gtkscrollbar.h"
  31 #include "gtkintl.h"
  32 #include "gtkprivate.h"
  33
  34 #include "a11y/gtkscrollbaraccessible.h"
  35
  36
  37 /**
  38  * SECTION:gtkscrollbar
  39  * @Short_description: A Scrollbar
  40  * @Title: GtkScrollbar
  41  * @See_also: #GtkAdjustment, #GtkScrolledWindow
  42  *
  43  * The #GtkScrollbar widget is a horizontal or vertical scrollbar,
  44  * depending on the value of the #GtkOrientable:orientation property.
  45  *
  46  * The position of the thumb in a scrollbar is controlled by the scroll
  47  * adjustments. See #GtkAdjustment for the fields in an adjustment - for
  48  * #GtkScrollbar, the #GtkAdjustment.value field represents the position
  49  * of the scrollbar, which must be between the #GtkAdjustment.lower field
  50  * and #GtkAdjustment.upper - #GtkAdjustment.page_size. The
  51  * #GtkAdjustment.page_size field represents the size of the visible
  52  * scrollable area. The #GtkAdjustment.step_increment and
  53  * #GtkAdjustment.page_increment fields are used when the user asks to
  54  * step down (using the small stepper arrows) or page down (using for
  55  * example the <keycap>PageDown</keycap> key).
  56  */
  57
  58
  59 static void gtk_scrollbar_style_updated (GtkWidget *widget);
  60
  61 G_DEFINE_TYPE (GtkScrollbar, gtk_scrollbar, GTK_TYPE_RANGE)
  62
  63 static void
  64 gtk_scrollbar_class_init (GtkScrollbarClass *class)
  65 {
  66   GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
  67
  68   widget_class->style_updated = gtk_scrollbar_style_updated;
  69
  70   gtk_widget_class_install_style_property (widget_class,
  71                                            g_param_spec_int ("min-slider-length",
  72                                                              P_("Minimum Slider Length"),
  73                                                              P_("Minimum length of scrollbar slider"),
  74                                                              0,
  75                                                              G_MAXINT,
  76                                                              21,
  77                                                              GTK_PARAM_READABLE));
  78
  79   gtk_widget_class_install_style_property (widget_class,
  80                                            g_param_spec_boolean ("fixed-slider-length",
  81                                                                  P_("Fixed slider size"),
  82                                                                  P_("Don't change slider size, just lock it to the minimum length"),
  83                                                                  FALSE,
  84                                                                  GTK_PARAM_READABLE));
  85
  86   gtk_widget_class_install_style_property (widget_class,
  87                                            g_param_spec_boolean ("has-backward-stepper",
  88                                                                  P_("Backward stepper"),
  89                                                                  P_("Display the standard backward arrow button"),
  90                                                                  TRUE,
  91                                                                  GTK_PARAM_READABLE));
  92
  93   gtk_widget_class_install_style_property (widget_class,
  94                                            g_param_spec_boolean ("has-forward-stepper",
  95                                                                  P_("Forward stepper"),
  96                                                                  P_("Display the standard forward arrow button"),
  97                                                                  TRUE,
  98                                                                  GTK_PARAM_READABLE));
  99
 100   gtk_widget_class_install_style_property (widget_class,
 101                                            g_param_spec_boolean ("has-secondary-backward-stepper",
 102                                                                  P_("Secondary backward stepper"),
 103                                                                  P_("Display a second backward arrow button on the opposite end of the scrollbar"),
 104                                                                  FALSE,
 105                                                                  GTK_PARAM_READABLE));
 106
 107   gtk_widget_class_install_style_property (widget_class,
 108                                            g_param_spec_boolean ("has-secondary-forward-stepper",
 109                                                                  P_("Secondary forward stepper"),
 110                                                                  P_("Display a second forward arrow button on the opposite end of the scrollbar"),
 111                                                                  FALSE,
 112                                                                  GTK_PARAM_READABLE));
 113
 114   gtk_widget_class_set_accessible_type (widget_class, GTK_TYPE_SCROLLBAR_ACCESSIBLE);
 115 }
 116
 117 static void
 118 gtk_scrollbar_init (GtkScrollbar *scrollbar)
 119 {
 120   GtkStyleContext *context;
 121
 122   context = gtk_widget_get_style_context (GTK_WIDGET (scrollbar));
 123   gtk_style_context_add_class (context, GTK_STYLE_CLASS_SCROLLBAR);
 124 }
 125
 126 static void
 127 gtk_scrollbar_style_updated (GtkWidget *widget)
 128 {
 129   GtkRange *range = GTK_RANGE (widget);
 130   gint slider_length;
 131   gboolean fixed_size;
 132   gboolean has_a, has_b, has_c, has_d;
 133
 134   gtk_widget_style_get (widget,
 135                         "min-slider-length", &slider_length,
 136                         "fixed-slider-length", &fixed_size,
 137                         "has-backward-stepper", &has_a,
 138                         "has-secondary-forward-stepper", &has_b,
 139                         "has-secondary-backward-stepper", &has_c,
 140                         "has-forward-stepper", &has_d,
 141                         NULL);
 142
 143   gtk_range_set_min_slider_size (range, slider_length);
 144   gtk_range_set_slider_size_fixed (range, fixed_size);
 145   _gtk_range_set_steppers (range,
 146                            has_a, has_b, has_c, has_d);
 147
 148   GTK_WIDGET_CLASS (gtk_scrollbar_parent_class)->style_updated (widget);
 149 }
 150
 151 /**
 152  * gtk_scrollbar_new:
 153  * @orientation: the scrollbar's orientation.
 154  * @adjustment: (allow-none): the #GtkAdjustment to use, or %NULL to create a new adjustment.
 155  *
 156  * Creates a new scrollbar with the given orientation.
 157  *
 158  * Return value:  the new #GtkScrollbar.
 159  *
 160  * Since: 3.0
 161  **/
 162 GtkWidget *
 163 gtk_scrollbar_new (GtkOrientation  orientation,
 164                    GtkAdjustment  *adjustment)
 165 {
 166   g_return_val_if_fail (adjustment == NULL || GTK_IS_ADJUSTMENT (adjustment),
 167                         NULL);
 168
 169   return g_object_new (GTK_TYPE_SCROLLBAR,
 170                        "orientation", orientation,
 171                        "adjustment",  adjustment,
 172                        NULL);
 173 }