[gnome-builder/gnome-builder-3-20] prefs: disable dark mode switch if GTK_THEME is set

[Christian Hergert <chergert src gnome org>]

commit 87d02a7b7f527fc53067209b0261e66adc56ef9f
Author: Christian Hergert <chergert redhat com>
Date:   Tue May 10 10:07:25 2016 +0300

    prefs: disable dark mode switch if GTK_THEME is set

 libide/preferences/ide-preferences-builtin.c |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)
---
diff --git a/libide/preferences/ide-preferences-builtin.c b/libide/preferences/ide-preferences-builtin.c
index f19a733..373bf3e 100644
--- a/libide/preferences/ide-preferences-builtin.c
+++ b/libide/preferences/ide-preferences-builtin.c
@@ -73,12 +73,14 @@ ide_preferences_builtin_register_appearance (IdePreferences *preferences)
 {
   GtkSourceStyleSchemeManager *manager;
   const gchar * const *scheme_ids;
+  GtkWidget *bin;
   gint i;
+  gint dark_mode;
 
   ide_preferences_add_page (preferences, "appearance", _("Appearance"), 0);
 
   ide_preferences_add_list_group (preferences, "appearance", "basic", _("Themes"), 0);
-  ide_preferences_add_switch (preferences, "appearance", "basic", "org.gnome.builder", "night-mode", NULL, 
NULL, _("Dark Theme"), _("Whether Builder should use a dark theme"), _("dark theme"), 0);
+  dark_mode = ide_preferences_add_switch (preferences, "appearance", "basic", "org.gnome.builder", 
"night-mode", NULL, NULL, _("Dark Theme"), _("Whether Builder should use a dark theme"), _("dark theme"), 0);
   ide_preferences_add_switch (preferences, "appearance", "basic", "org.gnome.builder.editor", 
"show-grid-lines", NULL, NULL, _("Grid Pattern"), _("Display a grid pattern underneath source code"), NULL, 
0);
 
   ide_preferences_add_list_group (preferences, "appearance", "schemes", NULL, 100);
@@ -103,6 +105,12 @@ ide_preferences_builtin_register_appearance (IdePreferences *preferences)
   ide_preferences_add_font_button (preferences, "appearance", "font", "org.gnome.builder.editor", 
"font-name", _("Editor"), C_("Keywords", "editor font monospace"), 0);
   /* XXX: This belongs in terminal addin */
   ide_preferences_add_font_button (preferences, "appearance", "font", "org.gnome.builder.terminal", 
"font-name", _("Terminal"), C_("Keywords", "terminal font monospace"), 0);
+
+  if (g_getenv ("GTK_THEME") != NULL)
+    {
+      bin = ide_preferences_get_widget (preferences, dark_mode);
+      gtk_widget_set_sensitive (bin, FALSE);
+    }
 }
 
 static void