Variant<>: Make this usable as an ouput parameter.

* glib/src/variant.[hg|ccg]: VariantBase: Added init(), like Value::init().
This just changes the gobject_, with appropriate unref and ref.
* gio/src/settings.[hg|ccg]: get_value(): Use an output parameter for the
VariantBase, instead of a return value, as we do for Value, allowing the
caller to use a derived (templated) type.
* examples/settings/settings.cc: Show how Variant<> can be used.

1 files changed, 9 insertions, 0 deletions

diff --git a/gio/src/settings.ccg b/gio/src/settings.ccg
index 342b70f5..feaba2aa 100644
--- a/gio/src/settings.ccg
+++ b/gio/src/settings.ccg
@@ -3,6 +3,15 @@
 namespace Gio
 {
 
+void Settings::get_value(const Glib::ustring& key, Glib::VariantBase& value)
+{
+  GVariant* const g_value = g_settings_get_value(gobj(), key.c_str());
+  if(!g_value)
+    return;
+
+  value.init(g_value, false /* don't take a reference */);
+}
+
 void Settings::bind(const Glib::ustring& key,
                     const Glib::PropertyProxy_Base& property_proxy,
                     SettingsBindFlags flags)