Get the main Gtk struct
Starts asynchronous initialization of the object implementing the interface. This must be done before any real use of the object after initial construction. If the object also implements #GInitable you can optionally call g_initable_init() instead.
Finishes asynchronous initialization and returns the result. See g_async_initable_init_async().
Finishes the async construction for the various g_async_initable_new calls, returning the created object or %NULL on error.
This is the asynchronous version of #GInitable; it behaves the same in all ways except that initialization is asynchronous. For more details see the descriptions on #GInitable.
A class may implement both the #GInitable and #GAsyncInitable interfaces.
Users of objects implementing this are not intended to use the interface method directly; instead it will be used automatically in various ways. For C applications you generally just call g_async_initable_new_async() directly, or indirectly via a foo_thing_new_async() wrapper. This will call g_async_initable_init_async() under the cover, calling back with %NULL and a set %GError on failure.
A typical implementation might look something like this:
|[<!-- language="C" --> enum { NOT_INITIALIZED, INITIALIZING, INITIALIZED };
static void _foo_ready_cb (Foo *self) { GList *l;
self->priv->state = INITIALIZED;
for (l = self->priv->init_results; l != NULL; l = l->next) { GTask *task = l->data;
if (self->priv->success) g_task_return_boolean (task, TRUE); else g_task_return_new_error (task, ...); g_object_unref (task); }
g_list_free (self->priv->init_results); self->priv->init_results = NULL; }
static void foo_init_async (GAsyncInitable *initable, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { Foo *self = FOO (initable); GTask *task;
task = g_task_new (initable, cancellable, callback, user_data);
switch (self->priv->state) { case NOT_INITIALIZED: _foo_get_ready (self); self->priv->init_results = g_list_append (self->priv->init_results, task); self->priv->state = INITIALIZING; break; case INITIALIZING: self->priv->init_results = g_list_append (self->priv->init_results, task); break; case INITIALIZED: if (!self->priv->success) g_task_return_new_error (task, ...); else g_task_return_boolean (task, TRUE); g_object_unref (task); break; } }
static gboolean foo_init_finish (GAsyncInitable *initable, GAsyncResult *result, GError **error) { g_return_val_if_fail (g_task_is_valid (result, initable), FALSE);
return g_task_propagate_boolean (G_TASK (result), error); }
static void foo_async_initable_iface_init (gpointer g_iface, gpointer data) { GAsyncInitableIface *iface = g_iface;
iface->init_async = foo_init_async; iface->init_finish = foo_init_finish; } ]|