display: Add UI to change nightlight color temperature

This adds a scale to change the color temperature between 2700K up to
6500K. A mark is added to the default value and a second one for
aesthetics.

Closes #147

panels/display/cc-night-light-dialog.c

@@ -35,6 +35,7 @@ struct _CcNightLightDialog {
   GtkWidget           *box_manual;
   GtkWidget           *infobar_disabled;
   GtkWidget           *night_light_widget;
+  GtkWidget           *scale_color_temperature;
   GtkWidget           *spinbutton_from_hours;
   GtkWidget           *spinbutton_from_minutes;
   GtkWidget           *spinbutton_to_hours;
@@ -49,6 +50,7 @@ struct _CcNightLightDialog {
   GtkAdjustment       *adjustment_from_minutes;
   GtkAdjustment       *adjustment_to_hours;
   GtkAdjustment       *adjustment_to_minutes;
+  GtkAdjustment       *adjustment_color_temperature;
 
   GSettings           *settings_display;
   GSettings           *settings_clock;
@@ -213,6 +215,10 @@ dialog_update_state (CcNightLightDialog *self)
 
   cc_night_light_widget_set_to (CC_NIGHT_LIGHT_WIDGET (self->night_light_widget), value);
 
+
+  value = (gdouble) g_settings_get_uint (self->settings_display, "night-light-temperature");
+  gtk_adjustment_set_value (self->adjustment_color_temperature, value);
+
   /* set new time */
   cc_night_light_widget_set_now (CC_NIGHT_LIGHT_WIDGET (self->night_light_widget), frac_day_from_dt (dt));
 }
@@ -343,6 +349,22 @@ dialog_time_to_value_changed_cb (GtkAdjustment      *adjustment,
   g_settings_set_double (self->settings_display, "night-light-schedule-to", value);
 }
 
+static void
+dialog_color_temperature_value_changed_cb (GtkAdjustment      *adjustment,
+                                           CcNightLightDialog *self)
+{
+  gdouble value;
+
+  if (self->ignore_value_changed)
+    return;
+
+  value = gtk_adjustment_get_value (adjustment);
+
+  g_debug ("new value = %.0f", value);
+
+  g_settings_set_uint (self->settings_display, "night-light-temperature", (guint) value);
+}
+
 static void
 dialog_color_properties_changed_cb (GDBusProxy         *proxy,
                                     GVariant           *changed_properties,
@@ -553,9 +575,11 @@ cc_night_light_dialog_class_init (CcNightLightDialogClass *klass)
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, adjustment_from_minutes);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, adjustment_to_hours);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, adjustment_to_minutes);
+  gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, adjustment_color_temperature);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, box_manual);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, infobar_disabled);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, night_light_widget);
+  gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, scale_color_temperature);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, spinbutton_from_hours);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, spinbutton_from_minutes);
   gtk_widget_class_bind_template_child (widget_class, CcNightLightDialog, spinbutton_to_hours);
@@ -574,6 +598,7 @@ cc_night_light_dialog_class_init (CcNightLightDialogClass *klass)
   gtk_widget_class_bind_template_callback (widget_class, dialog_mode_changed_cb);
   gtk_widget_class_bind_template_callback (widget_class, dialog_time_from_value_changed_cb);
   gtk_widget_class_bind_template_callback (widget_class, dialog_time_to_value_changed_cb);
+  gtk_widget_class_bind_template_callback (widget_class, dialog_color_temperature_value_changed_cb);
   gtk_widget_class_bind_template_callback (widget_class, dialog_undisable_clicked_cb);
 
   g_type_ensure (CC_TYPE_NIGHT_LIGHT_WIDGET);
@@ -587,6 +612,20 @@ cc_night_light_dialog_init (CcNightLightDialog *self)
 
   gtk_widget_init_template (GTK_WIDGET (self));
 
+  /* Add a mark at 4000 (default) and half way to daylight temperature.
+   * This result in three sections:
+   *  * 2700K - 4000K ("soft white" - our default)
+   *  * 4000K - 5250K
+   *  * 5250K - 6500K (daylight)
+   */
+  gtk_scale_add_mark (GTK_SCALE (self->scale_color_temperature),
+                      4000, GTK_POS_BOTTOM,
+                      NULL);
+
+  gtk_scale_add_mark (GTK_SCALE (self->scale_color_temperature),
+                      5250, GTK_POS_BOTTOM,
+                      NULL);
+
   self->cancellable = g_cancellable_new ();
   self->settings_display = g_settings_new (DISPLAY_SCHEMA);
 

panels/display/cc-night-light-dialog.ui

@@ -141,7 +141,7 @@
                         <property name="can_focus">False</property>
                         <property name="halign">start</property>
                         <property name="hexpand">True</property>
-                        <property name="label" translatable="yes">Schedule</property>
+                        <property name="label" translatable="yes">Color Temperature</property>
                         <attributes>
                           <attribute name="weight" value="bold"/>
                         </attributes>
@@ -151,6 +151,22 @@
                         <property name="top_attach">1</property>
                       </packing>
                     </child>
+                    <child>
+                      <object class="GtkLabel">
+                        <property name="visible">True</property>
+                        <property name="can_focus">False</property>
+                        <property name="halign">start</property>
+                        <property name="hexpand">True</property>
+                        <property name="label" translatable="yes">Schedule</property>
+                        <attributes>
+                          <attribute name="weight" value="bold"/>
+                        </attributes>
+                      </object>
+                      <packing>
+                        <property name="left_attach">0</property>
+                        <property name="top_attach">2</property>
+                      </packing>
+                    </child>
                     <child>
                       <object class="GtkSwitch" id="switch_enable">
                         <property name="visible">True</property>
@@ -163,6 +179,25 @@
                         <property name="top_attach">0</property>
                       </packing>
                     </child>
+                    <child>
+                      <object class="GtkScale" id="scale_color_temperature">
+                        <property name="visible">True</property>
+                        <property name="can_focus">True</property>
+                        <property name="hexpand">True</property>
+                        <property name="adjustment">adjustment_color_temperature</property>
+                        <property name="restrict_to_fill_level">False</property>
+                        <property name="fill_level">1</property>
+                        <property name="round_digits">0</property>
+                        <property name="digits">0</property>
+                        <property name="draw_value">False</property>
+                        <property name="has_origin">False</property>
+                        <property name="value_pos">bottom</property>
+                      </object>
+                      <packing>
+                        <property name="left_attach">1</property>
+                         <property name="top_attach">1</property>
+                       </packing>
+                     </child>
                     <child>
                       <object class="GtkButtonBox">
                         <property name="visible">True</property>
@@ -203,7 +238,7 @@
                       </object>
                       <packing>
                         <property name="left_attach">1</property>
-                        <property name="top_attach">1</property>
+                        <property name="top_attach">2</property>
                       </packing>
                     </child>
                   </object>
@@ -492,4 +527,11 @@
     <property name="page_increment">10</property>
     <signal name="value-changed" handler="dialog_time_to_value_changed_cb" object="CcNightLightDialog" swapped="no" />
   </object>
+  <object class="GtkAdjustment" id="adjustment_color_temperature">
+    <property name="lower">2700</property>
+    <property name="upper">6500</property>
+    <property name="step_increment">100</property>
+    <property name="page_increment">500</property>
+    <signal name="value-changed" handler="dialog_color_temperature_value_changed_cb" object="CcNightLightDialog" swapped="no" />
+  </object>
 </interface>
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