[gtk+] Fixed minimum increment calculation of GailScaleButton.

[Javier Jardón <jjardon src gnome org>]

commit d8a90be3706cb2bb65ddf36d07048ac14529548f
Author: Szilárd Pfeiffer <mailbox pfeifferszilard hu>
Date:   Mon Aug 30 20:15:09 2010 +0200

    Fixed minimum increment calculation of GailScaleButton.
    
    Also implemented to use the adjustment to determine the current, minimum,
    maximum values and mimimum increment just as the other widgets which have
    adjustment.
    
    Fixes https://bugzilla.gnome.org/show_bug.cgi?id=626710

 modules/other/gail/gailscalebutton.c |  153 +++++++++++++++++++++++-----------
 modules/other/gail/gailscalebutton.h |    2 +
 2 files changed, 106 insertions(+), 49 deletions(-)
---
diff --git a/modules/other/gail/gailscalebutton.c b/modules/other/gail/gailscalebutton.c
index 9f2130e..820d767 100644
--- a/modules/other/gail/gailscalebutton.c
+++ b/modules/other/gail/gailscalebutton.c
@@ -30,12 +30,12 @@ static void gail_scale_button_class_init (GailScaleButtonClass *klass);
 static void gail_scale_button_init       (GailScaleButton      *button);
 
 /* GailWidget */
-static void gail_scale_button_notify_gtk (GObject    *obj,
-                                          GParamSpec *pspec);
+static void gail_scale_button_real_notify_gtk (GObject    *obj,
+                                               GParamSpec *pspec);
 
 /* AtkObject */
-static void gail_scale_button_initialize (AtkObject *obj,
-                                          gpointer   data);
+static void gail_scale_button_real_initialize (AtkObject *obj,
+                                               gpointer   data);
 
 /* AtkAction */
 static void                  atk_action_interface_init        (AtkActionIface *iface);
@@ -64,6 +64,8 @@ static void	gail_scale_button_get_minimum_increment (AtkValue       *obj,
                                                          GValue         *value);
 static gboolean	gail_scale_button_set_current_value     (AtkValue       *obj,
                                                          const GValue   *value);
+static void     gail_scale_button_value_changed         (GtkAdjustment  *adjustment,
+                                                         gpointer       data);
 
 G_DEFINE_TYPE_WITH_CODE (GailScaleButton, gail_scale_button, GAIL_TYPE_BUTTON,
                          G_IMPLEMENT_INTERFACE (ATK_TYPE_ACTION, atk_action_interface_init)
@@ -75,9 +77,9 @@ gail_scale_button_class_init (GailScaleButtonClass *klass)
   AtkObjectClass *atk_object_class = ATK_OBJECT_CLASS (klass);
   GailWidgetClass *widget_class = GAIL_WIDGET_CLASS (klass);
 
-  atk_object_class->initialize = gail_scale_button_initialize;
+  atk_object_class->initialize = gail_scale_button_real_initialize;
 
-  widget_class->notify_gtk = gail_scale_button_notify_gtk;
+  widget_class->notify_gtk = gail_scale_button_real_notify_gtk;
 }
 
 static void
@@ -86,11 +88,32 @@ gail_scale_button_init (GailScaleButton *button)
 }
 
 static void
-gail_scale_button_initialize (AtkObject *obj,
-                              gpointer   data)
+gail_scale_button_real_initialize (AtkObject *obj,
+                                   gpointer  data)
 {
+  GailScaleButton *scale_button = GAIL_SCALE_BUTTON (obj);
+  GtkScaleButton *gtk_scale_button;
+  GtkAdjustment *gtk_adjustment;
+
   ATK_OBJECT_CLASS (gail_scale_button_parent_class)->initialize (obj, data);
 
+  gtk_scale_button = GTK_SCALE_BUTTON (data);
+  gtk_adjustment = gtk_scale_button_get_adjustment (gtk_scale_button);
+  /*
+   * If a GtkAdjustment already exists for the scale_button,
+   * create the GailAdjustment
+   */
+  if (gtk_adjustment)
+    {
+      scale_button->adjustment = gail_adjustment_new (gtk_adjustment);
+      g_signal_connect (gtk_adjustment,
+                        "value-changed",
+                        G_CALLBACK (gail_scale_button_value_changed),
+                        obj);
+    }
+  else
+    scale_button->adjustment = NULL;
+
   obj->role = ATK_ROLE_SLIDER;
 }
 
@@ -187,96 +210,95 @@ static void
 gail_scale_button_get_current_value (AtkValue *obj,
                                      GValue   *value)
 {
-  GtkScaleButton *gtk_scale_button;
+  GailScaleButton *scale_button;
 
   g_return_if_fail (GAIL_IS_SCALE_BUTTON (obj));
 
-  gtk_scale_button = GTK_SCALE_BUTTON (gtk_accessible_get_widget (GTK_ACCESSIBLE (obj)));
+  scale_button = GAIL_SCALE_BUTTON (obj);
+  if (scale_button->adjustment == NULL)
+    /*
+     * Adjustment has not been specified
+     */
+    return;
 
-  g_value_set_double (g_value_init (value, G_TYPE_DOUBLE),
-                      gtk_scale_button_get_value (gtk_scale_button));
+  atk_value_get_current_value (ATK_VALUE (scale_button->adjustment), value);
 }
 
 static void
 gail_scale_button_get_maximum_value (AtkValue *obj,
                                      GValue   *value)
 {
-  GtkWidget *gtk_widget;
-  GtkAdjustment *adj;
+  GailScaleButton *scale_button;
 
   g_return_if_fail (GAIL_IS_SCALE_BUTTON (obj));
 
-  gtk_widget = gtk_accessible_get_widget (GTK_ACCESSIBLE (obj));
-  if (gtk_widget == NULL)
+  scale_button = GAIL_SCALE_BUTTON (obj);
+  if (scale_button->adjustment == NULL)
+    /*
+     * Adjustment has not been specified
+     */
     return;
 
-  adj = gtk_scale_button_get_adjustment (GTK_SCALE_BUTTON (gtk_widget));
-  if (adj != NULL)
-    g_value_set_double (g_value_init (value, G_TYPE_DOUBLE),
-                        adj->upper);
+  atk_value_get_maximum_value (ATK_VALUE (scale_button->adjustment), value);
 }
 
 static void
 gail_scale_button_get_minimum_value (AtkValue *obj,
                                      GValue   *value)
 {
-  GtkWidget *gtk_widget;
-  GtkAdjustment *adj;
+  GailScaleButton *scale_button;
 
   g_return_if_fail (GAIL_IS_SCALE_BUTTON (obj));
 
-  gtk_widget = gtk_accessible_get_widget (GTK_ACCESSIBLE (obj));
-  if (gtk_widget == NULL)
+  scale_button = GAIL_SCALE_BUTTON (obj);
+  if (scale_button->adjustment == NULL)
+    /*
+     * Adjustment has not been specified
+     */
     return;
 
-  adj = gtk_scale_button_get_adjustment (GTK_SCALE_BUTTON (gtk_widget));
-  if (adj != NULL)
-    g_value_set_double (g_value_init (value, G_TYPE_DOUBLE),
-                        adj->lower);
+  atk_value_get_minimum_value (ATK_VALUE (scale_button->adjustment), value);
 }
 
 static void
 gail_scale_button_get_minimum_increment (AtkValue *obj,
                                          GValue   *value)
 {
-  GtkWidget *gtk_widget;
-  GtkAdjustment *adj;
+  GailScaleButton *scale_button;
 
   g_return_if_fail (GAIL_IS_SCALE_BUTTON (obj));
 
-  gtk_widget = gtk_accessible_get_widget (GTK_ACCESSIBLE (obj));
-  if (gtk_widget == NULL)
+  scale_button = GAIL_SCALE_BUTTON (obj);
+  if (scale_button->adjustment == NULL)
+    /*
+     * Adjustment has not been specified
+     */
     return;
 
-  adj = gtk_scale_button_get_adjustment (GTK_SCALE_BUTTON (gtk_widget));
-  if (adj != NULL)
-    g_value_set_double (g_value_init (value, G_TYPE_DOUBLE),
-                        adj->step_increment);
+  atk_value_get_minimum_increment (ATK_VALUE (scale_button->adjustment), value);
 }
 
 static gboolean
 gail_scale_button_set_current_value (AtkValue     *obj,
                                      const GValue *value)
 {
-  GtkWidget *gtk_widget;
+  GailScaleButton *scale_button;
 
   g_return_val_if_fail (GAIL_IS_SCALE_BUTTON (obj), FALSE);
 
-  gtk_widget = gtk_accessible_get_widget (GTK_ACCESSIBLE (obj));
-  if (gtk_widget == NULL)
+  scale_button = GAIL_SCALE_BUTTON (obj);
+  if (scale_button->adjustment == NULL)
+    /*
+     * Adjustment has not been specified
+     */
     return FALSE;
 
-  if (G_VALUE_HOLDS_DOUBLE (value))
-    {
-      gtk_scale_button_set_value (GTK_SCALE_BUTTON (gtk_widget), g_value_get_double (value));
-      return TRUE;
-    }
-  return FALSE;
+  return atk_value_set_current_value (ATK_VALUE (scale_button->adjustment), value);
 }
 
 static void
-gail_scale_button_notify_gtk (GObject    *obj,
-                              GParamSpec *pspec)
+gail_scale_button_real_notify_gtk (GObject    *obj,
+                                   GParamSpec *pspec)
 {
   GtkScaleButton *gtk_scale_button;
   GailScaleButton *scale_button;
@@ -286,9 +308,29 @@ gail_scale_button_notify_gtk (GObject    *obj,
   gtk_scale_button = GTK_SCALE_BUTTON (obj);
   scale_button = GAIL_SCALE_BUTTON (gtk_widget_get_accessible (GTK_WIDGET (gtk_scale_button)));
 
-  if (strcmp (pspec->name, "value") == 0)
+  if (strcmp (pspec->name, "adjustment") == 0)
     {
-      g_object_notify (G_OBJECT (scale_button), "accessible-value");
+      /*
+       * Get rid of the GailAdjustment for the GtkAdjustment
+       * which was associated with the scale_button.
+       */
+      GtkAdjustment* gtk_adjustment;
+
+      if (scale_button->adjustment)
+        {
+          g_object_unref (scale_button->adjustment);
+          scale_button->adjustment = NULL;
+        }
+      /*
+       * Create the GailAdjustment when notify for "adjustment" property
+       * is received
+       */
+      gtk_adjustment = gtk_scale_button_get_adjustment (gtk_scale_button);
+      scale_button->adjustment = gail_adjustment_new (gtk_adjustment);
+      g_signal_connect (gtk_adjustment,
+                        "value-changed",
+                        G_CALLBACK (gail_scale_button_value_changed),
+                        scale_button);
     }
   else
     {
@@ -296,4 +338,17 @@ gail_scale_button_notify_gtk (GObject    *obj,
     }
 }
 
+static void
+gail_scale_button_value_changed (GtkAdjustment    *adjustment,
+                                 gpointer         data)
+{
+  GailScaleButton *scale_button;
+
+  gail_return_if_fail (adjustment != NULL);
+  gail_return_if_fail (data != NULL);
+
+  scale_button = GAIL_SCALE_BUTTON (data);
+
+  g_object_notify (G_OBJECT (scale_button), "accessible-value");
+}
 
diff --git a/modules/other/gail/gailscalebutton.h b/modules/other/gail/gailscalebutton.h
index d0ec878..ce79b47 100644
--- a/modules/other/gail/gailscalebutton.h
+++ b/modules/other/gail/gailscalebutton.h
@@ -38,6 +38,8 @@ typedef struct _GailScaleButtonClass              GailScaleButtonClass;
 struct _GailScaleButton
 {
   GailButton parent;
+
+  AtkObject *adjustment;
 };
 
 struct _GailScaleButtonClass