Sets our main struct and passes it to the parent class.
Creates a #GSimpleAsyncResult.
Creates a #GSimpleAsyncResult from an error condition.
Completes an asynchronous I/O job immediately. Must be called in the thread where the asynchronous result was to be delivered, as it invokes the callback directly. If you are in a different thread use g_simple_async_result_complete_in_idle().
Completes an asynchronous function in an idle handler in the [thread-default main context][g-main-context-push-thread-default] of the thread that @simple was initially created in (and re-pushes that context around the invocation of the callback).
Gets the operation result boolean from within the asynchronous result.
Gets a pointer result as returned by the asynchronous function.
Gets a gssize from the asynchronous result.
Get the main Gtk struct
Gets the source tag for the #GSimpleAsyncResult.
the main Gtk struct as a void*
Propagates an error from within the simple asynchronous result to a given destination.
Runs the asynchronous job in a separate thread and then calls g_simple_async_result_complete_in_idle() on @simple to return the result to the appropriate main loop.
Sets a #GCancellable to check before dispatching results.
Sets an error within the asynchronous result without a #GError. Unless writing a binding, see g_simple_async_result_set_error().
Sets the result from a #GError.
Sets whether to handle cancellation within the asynchronous operation.
Sets the operation result to a boolean within the asynchronous result.
Sets the operation result within the asynchronous result to a pointer.
Sets the operation result within the asynchronous result to the given @op_res.
Sets the result from @error, and takes over the caller's ownership of @error, so the caller does not need to free it any more.
Ensures that the data passed to the _finish function of an async operation is consistent. Three checks are performed.
Reports an error in an idle function. Similar to g_simple_async_report_error_in_idle(), but takes a #GError rather than building a new one.
Reports an error in an idle function. Similar to g_simple_async_report_gerror_in_idle(), but takes over the caller's ownership of @error, so the caller does not have to free it any more.
the main Gtk struct
the main Gtk struct
Get the main Gtk struct
the main Gtk struct as a void*
Gets a D Object from the objects table of associations.
The notify signal is emitted on an object when one of its properties has been changed. Note that getting this signal doesn't guarantee that the value of the property has actually changed, it may also be emitted when the setter for the property is called to reinstate the previous value.
Find the #GParamSpec with the given name for an interface. Generally, the interface vtable passed in as @g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().
Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created #GParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.
Lists the properties of an interface.Generally, the interface vtable passed in as @g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().
Increases the reference count of the object by one and sets a callback to be called when all other references to the object are dropped, or when this is already the last reference to the object and another reference is established.
Adds a weak reference from weak_pointer to @object to indicate that the pointer located at @weak_pointer_location is only valid during the lifetime of @object. When the @object is finalized, @weak_pointer will be set to %NULL.
Creates a binding between @source_property on @source and @target_property on @target. Whenever the @source_property is changed the @target_property is updated using the same value. For instance:
Complete version of g_object_bind_property().
Creates a binding between @source_property on @source and @target_property on @target, allowing you to set the transformation functions to be used by the binding.
This is a variant of g_object_get_data() which returns a 'duplicate' of the value. @dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.
This is a variant of g_object_get_qdata() which returns a 'duplicate' of the value. @dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.
This function is intended for #GObject implementations to re-enforce a floating[floating-ref] object reference. Doing this is seldom required: all #GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().
Increases the freeze count on @object. If the freeze count is non-zero, the emission of "notify" signals on @object is stopped. The signals are queued until the freeze count is decreased to zero. Duplicate notifications are squashed so that at most one #GObject::notify signal is emitted for each property modified while the object is frozen.
Gets a named field from the objects table of associations (see g_object_set_data()).
Gets a property of an object. @value must have been initialized to the expected type of the property (or a type to which the expected type can be transformed) using g_value_init().
This function gets back user data pointers stored via g_object_set_qdata().
Gets properties of an object.
Checks whether @object has a floating[floating-ref] reference.
Emits a "notify" signal for the property @property_name on @object.
Emits a "notify" signal for the property specified by @pspec on @object.
Increases the reference count of @object.
Increase the reference count of @object, and possibly remove the floating[floating-ref] reference, if @object has a floating reference.
Removes a reference added with g_object_add_toggle_ref(). The reference count of the object is decreased by one.
Removes a weak reference from @object that was previously added using g_object_add_weak_pointer(). The @weak_pointer_location has to match the one used with g_object_add_weak_pointer().
Compares the user data for the key @key on @object with @oldval, and if they are the same, replaces @oldval with @newval.
Compares the user data for the key @quark on @object with @oldval, and if they are the same, replaces @oldval with @newval.
Releases all references to other objects. This can be used to break reference cycles.
Each object carries around a table of associations from strings to pointers. This function lets you set an association.
Like g_object_set_data() except it adds notification for when the association is destroyed, either by setting it to a different value or when the object is destroyed.
Sets a property on an object.
This sets an opaque, named pointer on an object. The name is specified through a #GQuark (retrived e.g. via g_quark_from_static_string()), and the pointer can be gotten back from the @object with g_object_get_qdata() until the @object is finalized. Setting a previously set user data pointer, overrides (frees) the old pointer set, using #NULL as pointer essentially removes the data stored.
This function works like g_object_set_qdata(), but in addition, a void (*destroy) (gpointer) function may be specified which is called with @data as argument when the @object is finalized, or the data is being overwritten by a call to g_object_set_qdata() with the same @quark.
Sets properties on an object.
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
This function gets back user data pointers stored via g_object_set_qdata() and removes the @data from object without invoking its destroy() function (if any was set). Usually, calling this function is only required to update user data pointers with a destroy notifier, for example: |[<!-- language="C" --> void object_add_to_user_list (GObject *object, const gchar *new_string) { // the quark, naming the object data GQuark quark_string_list = g_quark_from_static_string ("my-string-list"); // retrive the old string list GList *list = g_object_steal_qdata (object, quark_string_list);
Reverts the effect of a previous call to g_object_freeze_notify(). The freeze count is decreased on @object and when it reaches zero, queued "notify" signals are emitted.
Decreases the reference count of @object. When its reference count drops to 0, the object is finalized (i.e. its memory is freed).
This function essentially limits the life time of the @closure to the life time of the object. That is, when the object is finalized, the @closure is invalidated by calling g_closure_invalidate() on it, in order to prevent invocations of the closure with a finalized (nonexisting) object. Also, g_object_ref() and g_object_unref() are added as marshal guards to the @closure, to ensure that an extra reference count is held on @object during invocation of the @closure. Usually, this function will be called on closures that use this @object as closure data.
Adds a weak reference callback to an object. Weak references are used for notification when an object is finalized. They are called "weak references" because they allow you to safely hold a pointer to an object without calling g_object_ref() (g_object_ref() adds a strong reference, that is, forces the object to stay alive).
Removes a weak reference callback to an object.
Clears a reference to a #GObject.
Get the main Gtk struct
the main Gtk struct as a void*
Gets the source object from a #GAsyncResult.
Gets the user data from a #GAsyncResult.
Checks if @res has the given @source_tag (generally a function pointer indicating the function @res was created by).
If @res is a #GSimpleAsyncResult, this is equivalent to g_simple_async_result_propagate_error(). Otherwise it returns %FALSE.
// In this example, we assume that baked_cb is called as a callback from // the mainloop, so it's safe to complete the operation synchronously here. // If, however, _baker_prepare_cake () might call its callback without // first returning to the mainloop — inadvisable, but some APIs do so — // we would need to use g_simple_async_result_complete_in_idle(). g_simple_async_result_complete (result); g_object_unref (result); }
void baker_bake_cake_async (Baker *self, guint radius, GAsyncReadyCallback callback, gpointer user_data) { GSimpleAsyncResult *simple; Cake *cake;
if (radius < 3) { g_simple_async_report_error_in_idle (G_OBJECT (self), callback, user_data, BAKER_ERRORS, BAKER_ERROR_TOO_SMALL, "%ucm radius cakes are silly", radius); return; }
simple = g_simple_async_result_new (G_OBJECT (self), callback, user_data, baker_bake_cake_async); cake = _baker_get_cached_cake (self, radius);
if (cake != NULL) { g_simple_async_result_set_op_res_gpointer (simple, g_object_ref (cake), g_object_unref); g_simple_async_result_complete_in_idle (simple); g_object_unref (simple); // Drop the reference returned by _baker_get_cached_cake(); // the GSimpleAsyncResult has taken its own reference. g_object_unref (cake); return; }
_baker_prepare_cake (self, radius, baked_cb, simple); }
Cake * baker_bake_cake_finish (Baker *self, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple; Cake *cake;
g_return_val_if_fail (g_simple_async_result_is_valid (result, G_OBJECT (self), baker_bake_cake_async), NULL);
simple = (GSimpleAsyncResult *) result;
if (g_simple_async_result_propagate_error (simple, error)) return NULL;
cake = CAKE (g_simple_async_result_get_op_res_gpointer (simple)); return g_object_ref (cake); } ]|
As of GLib 2.46, #GSimpleAsyncResult is deprecated in favor of #GTask, which provides a simpler API.
#GSimpleAsyncResult implements #GAsyncResult.
GSimpleAsyncResult handles #GAsyncReadyCallbacks, error reporting, operation cancellation and the final state of an operation, completely transparent to the application. Results can be returned as a pointer e.g. for functions that return data that is collected asynchronously, a boolean value for checking the success or failure of an operation, or a #gssize for operations which return the number of bytes modified by the operation; all of the simple return cases are covered.
Most of the time, an application will not need to know of the details of this API; it is handled transparently, and any necessary operations are handled by #GAsyncResult's interface. However, if implementing a new GIO module, for writing language bindings, or for complex applications that need better control of how asynchronous operations are completed, it is important to understand this functionality.
GSimpleAsyncResults are tagged with the calling function to ensure that asynchronous functions and their finishing functions are used together correctly.
To create a new #GSimpleAsyncResult, call g_simple_async_result_new(). If the result needs to be created for a #GError, use g_simple_async_result_new_from_error() or g_simple_async_result_new_take_error(). If a #GError is not available (e.g. the asynchronous operation's doesn't take a #GError argument), but the result still needs to be created for an error condition, use g_simple_async_result_new_error() (or g_simple_async_result_set_error_va() if your application or binding requires passing a variable argument list directly), and the error can then be propagated through the use of g_simple_async_result_propagate_error().
An asynchronous operation can be made to ignore a cancellation event by calling g_simple_async_result_set_handle_cancellation() with a #GSimpleAsyncResult for the operation and %FALSE. This is useful for operations that are dangerous to cancel, such as close (which would cause a leak if cancelled before being run).
GSimpleAsyncResult can integrate into GLib's event loop, #GMainLoop, or it can use #GThreads. g_simple_async_result_complete() will finish an I/O task directly from the point where it is called. g_simple_async_result_complete_in_idle() will finish it from an idle handler in the [thread-default main context][g-main-context-push-thread-default] . g_simple_async_result_run_in_thread() will run the job in a separate thread and then deliver the result to the thread-default main context.
To set the results of an asynchronous function, g_simple_async_result_set_op_res_gpointer(), g_simple_async_result_set_op_res_gboolean(), and g_simple_async_result_set_op_res_gssize() are provided, setting the operation's result to a gpointer, gboolean, or gssize, respectively.
Likewise, to get the result of an asynchronous function, g_simple_async_result_get_op_res_gpointer(), g_simple_async_result_get_op_res_gboolean(), and g_simple_async_result_get_op_res_gssize() are provided, getting the operation's result as a gpointer, gboolean, and gssize, respectively.
For the details of the requirements implementations must respect, see #GAsyncResult. A typical implementation of an asynchronous operation using GSimpleAsyncResult looks something like this:
|[<!-- language="C" --> static void baked_cb (Cake *cake, gpointer user_data) { // In this example, this callback is not given a reference to the cake, // so the GSimpleAsyncResult has to take a reference to it. GSimpleAsyncResult *result = user_data;
if (cake == NULL) g_simple_async_result_set_error (result, BAKER_ERRORS, BAKER_ERROR_NO_FLOUR, "Go to the supermarket"); else g_simple_async_result_set_op_res_gpointer (result, g_object_ref (cake), g_object_unref);