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, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 /*
  20  * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
  21  * file for a list of people on the GTK+ Team.  See the ChangeLog
  22  * files for a list of changes.  These files are distributed with
  23  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  24  */
  25
  26 #include "config.h"
  27
  28 #include "gtkscrollbar.h"
  29 #include "gtkintl.h"
  30 #include "gtkprivate.h"
  31
  32 #include "a11y/gtkscrollbaraccessible.h"
  33
  34
  35 /**
  36  * SECTION:gtkscrollbar
  37  * @Short_description: A Scrollbar
  38  * @Title: GtkScrollbar
  39  * @See_also: #GtkAdjustment, #GtkScrolledWindow
  40  *
  41  * The #GtkScrollbar widget is a horizontal or vertical scrollbar,
  42  * depending on the value of the #GtkOrientable:orientation property.
  43  *
  44  * The position of the thumb in a scrollbar is controlled by the scroll
  45  * adjustments. See #GtkAdjustment for the fields in an adjustment - for
  46  * #GtkScrollbar, the #GtkAdjustment.value field represents the position
  47  * of the scrollbar, which must be between the #GtkAdjustment.lower field
  48  * and #GtkAdjustment.upper - #GtkAdjustment.page_size. The
  49  * #GtkAdjustment.page_size field represents the size of the visible
  50  * scrollable area. The #GtkAdjustment.step_increment and
  51  * #GtkAdjustment.page_increment fields are used when the user asks to
  52  * step down (using the small stepper arrows) or page down (using for
  53  * example the <keycap>PageDown</keycap> key).
  54  */
  55
  56
  57 static void gtk_scrollbar_style_updated (GtkWidget *widget);
  58
  59 G_DEFINE_TYPE (GtkScrollbar, gtk_scrollbar, GTK_TYPE_RANGE)
  60
  61 static void
  62 gtk_scrollbar_class_init (GtkScrollbarClass *class)
  63 {
  64   GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
  65
  66   widget_class->style_updated = gtk_scrollbar_style_updated;
  67
  68   gtk_widget_class_install_style_property (widget_class,
  69                                            g_param_spec_int ("min-slider-length",
  70                                                              P_("Minimum Slider Length"),
  71                                                              P_("Minimum length of scrollbar slider"),
  72                                                              0,
  73                                                              G_MAXINT,
  74                                                              21,
  75                                                              GTK_PARAM_READABLE));
  76
  77   gtk_widget_class_install_style_property (widget_class,
  78                                            g_param_spec_boolean ("fixed-slider-length",
  79                                                                  P_("Fixed slider size"),
  80                                                                  P_("Don't change slider size, just lock it to the minimum length"),
  81                                                                  FALSE,
  82                                                                  GTK_PARAM_READABLE));
  83
  84   gtk_widget_class_install_style_property (widget_class,
  85                                            g_param_spec_boolean ("has-backward-stepper",
  86                                                                  P_("Backward stepper"),
  87                                                                  P_("Display the standard backward arrow button"),
  88                                                                  TRUE,
  89                                                                  GTK_PARAM_READABLE));
  90
  91   gtk_widget_class_install_style_property (widget_class,
  92                                            g_param_spec_boolean ("has-forward-stepper",
  93                                                                  P_("Forward stepper"),
  94                                                                  P_("Display the standard forward arrow button"),
  95                                                                  TRUE,
  96                                                                  GTK_PARAM_READABLE));
  97
  98   gtk_widget_class_install_style_property (widget_class,
  99                                            g_param_spec_boolean ("has-secondary-backward-stepper",
 100                                                                  P_("Secondary backward stepper"),
 101                                                                  P_("Display a second backward arrow button on the opposite end of the scrollbar"),
 102                                                                  FALSE,
 103                                                                  GTK_PARAM_READABLE));
 104
 105   gtk_widget_class_install_style_property (widget_class,
 106                                            g_param_spec_boolean ("has-secondary-forward-stepper",
 107                                                                  P_("Secondary forward stepper"),
 108                                                                  P_("Display a second forward arrow button on the opposite end of the scrollbar"),
 109                                                                  FALSE,
 110                                                                  GTK_PARAM_READABLE));
 111
 112   gtk_widget_class_set_accessible_type (widget_class, GTK_TYPE_SCROLLBAR_ACCESSIBLE);
 113 }
 114
 115 static void
 116 gtk_scrollbar_init (GtkScrollbar *scrollbar)
 117 {
 118   GtkStyleContext *context;
 119
 120   context = gtk_widget_get_style_context (GTK_WIDGET (scrollbar));
 121   gtk_style_context_add_class (context, GTK_STYLE_CLASS_SCROLLBAR);
 122 }
 123
 124 static void
 125 gtk_scrollbar_style_updated (GtkWidget *widget)
 126 {
 127   GtkRange *range = GTK_RANGE (widget);
 128   gint slider_length;
 129   gboolean fixed_size;
 130   gboolean has_a, has_b, has_c, has_d;
 131
 132   gtk_widget_style_get (widget,
 133                         "min-slider-length", &slider_length,
 134                         "fixed-slider-length", &fixed_size,
 135                         "has-backward-stepper", &has_a,
 136                         "has-secondary-forward-stepper", &has_b,
 137                         "has-secondary-backward-stepper", &has_c,
 138                         "has-forward-stepper", &has_d,
 139                         NULL);
 140
 141   gtk_range_set_min_slider_size (range, slider_length);
 142   gtk_range_set_slider_size_fixed (range, fixed_size);
 143   _gtk_range_set_steppers (range,
 144                            has_a, has_b, has_c, has_d);
 145
 146   GTK_WIDGET_CLASS (gtk_scrollbar_parent_class)->style_updated (widget);
 147 }
 148
 149 /**
 150  * gtk_scrollbar_new:
 151  * @orientation: the scrollbar's orientation.
 152  * @adjustment: (allow-none): the #GtkAdjustment to use, or %NULL to create a new adjustment.
 153  *
 154  * Creates a new scrollbar with the given orientation.
 155  *
 156  * Return value:  the new #GtkScrollbar.
 157  *
 158  * Since: 3.0
 159  **/
 160 GtkWidget *
 161 gtk_scrollbar_new (GtkOrientation  orientation,
 162                    GtkAdjustment  *adjustment)
 163 {
 164   g_return_val_if_fail (adjustment == NULL || GTK_IS_ADJUSTMENT (adjustment),
 165                         NULL);
 166
 167   return g_object_new (GTK_TYPE_SCROLLBAR,
 168                        "orientation", orientation,
 169                        "adjustment",  adjustment,
 170                        NULL);
 171 }