VariantBuilder.open

Opens a subcontainer inside the given builder. When done adding items to the subcontainer, Variant.builderClose must be called. type is the type of the container: so to build a tuple of several values, type must include the tuple itself.

It is an error to call this function in any way that would cause an inconsistent value to be constructed (ie: adding too many values or a value of an incorrect type).

Example of building a nested variant:

GVariantBuilder builder;
guint32 some_number = get_number ();
g_autoptr (GHashTable) some_dict = get_dict ();
GHashTableIter iter;
const gchar *key;
const GVariant *value;
g_autoptr (GVariant) output = NULL;

g_variant_builder_init (&builder, G_VARIANT_TYPE ("(ua{sv})"));
g_variant_builder_add (&builder, "u", some_number);
g_variant_builder_open (&builder, G_VARIANT_TYPE ("a{sv}"));

g_hash_table_iter_init (&iter, some_dict);
while (g_hash_table_iter_next (&iter, (gpointer *) &key, (gpointer *) &value))
{
g_variant_builder_open (&builder, G_VARIANT_TYPE ("{sv}"));
g_variant_builder_add (&builder, "s", key);
g_variant_builder_add (&builder, "v", value);
g_variant_builder_close (&builder);
}

g_variant_builder_close (&builder);

output = g_variant_builder_end (&builder);