[retro-gtk/wip/aplazas/options: 2/3] option: Add the 'value-changed' signal

[Adrien Plazas <aplazas src gnome org>]

commit cd782a0b8a604fc829c18302e37b7d98aa79fe5e
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Fri Nov 24 10:55:20 2017 +0100

    option: Add the 'value-changed' signal

 retro-gtk/retro-option.c |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/retro-gtk/retro-option.c b/retro-gtk/retro-option.c
index 1430f0c..8c8a7ce 100644
--- a/retro-gtk/retro-option.c
+++ b/retro-gtk/retro-option.c
@@ -13,6 +13,13 @@ struct _RetroOption
 
 G_DEFINE_TYPE (RetroOption, retro_option, G_TYPE_OBJECT)
 
+enum {
+  SIG_VALUE_CHANGED,
+  N_SIGNALS,
+};
+
+static guint signals[N_SIGNALS];
+
 #define RETRO_OPTION_ERROR (retro_option_error_quark ())
 
 enum {
@@ -43,6 +50,13 @@ retro_option_class_init (RetroOptionClass *klass)
   GObjectClass *object_class = G_OBJECT_CLASS (klass);
 
   object_class->finalize = retro_option_finalize;
+
+  signals[SIG_VALUE_CHANGED] =
+    g_signal_new ("value-changed", RETRO_TYPE_OPTION, G_SIGNAL_RUN_LAST,
+                  0, NULL, NULL,
+                  g_cclosure_marshal_VOID__STRING,
+                  G_TYPE_NONE,
+                  0);
 }
 
 static void
@@ -111,6 +125,8 @@ retro_option_set_value (RetroOption  *self,
   }
 
   self->value = i;
+
+  g_signal_emit (self, signals[SIG_VALUE_CHANGED], 0);
 }
 
 RetroOption *