class: GWeakRef

[28:7] extends: object

A structure containing a weak reference to a #GObject. A GWeakRef can either be empty (i.e. point to %NULL), or point to an object for as long as at least one "strong" reference to that object exists. Before the object's #GObjectClass.dispose method is called, every #GWeakRef associated with becomes empty (i.e. points to %NULL). Like #GValue, #GWeakRef can be statically allocated, stack- or heap-allocated, or embedded in larger structures. Unlike g_object_weak_ref() and g_object_add_weak_pointer(), this weak reference is thread-safe: converting a weak pointer to a reference is atomic with respect to invalidation of weak pointers to destroyed objects. If the object's #GObjectClass.dispose method results in additional references to the object being held (‘re-referencing’), any #GWeakRefs taken before it was disposed will continue to point to %NULL. Any #GWeakRefs taken during disposal and after re-referencing, or after disposal has returned due to the re-referencing, will continue to point to the object until its refcount goes back to zero, at which point they too will be invalidated. It is invalid to take a #GWeakRef on an object during #GObjectClass.dispose without first having or creating a strong reference to the object.

Members

handleObj
lib
retainedCallbacks
signalHandlerNames
signalSetterHandlers

Methods

GWeakRef (Handle = null)

Creates a new WeakRef by wrapping a native handle or another wrapper.
- @p Handle is the native handle or another wrapper whose handle to adopt.
toNativeHandle (Source)

Normalizes a constructor argument into a raw pointer carrier. Accepts a raw NativeHandle, a raw NativeBuffer returned from fn.call(...), another generated wrapper exposing handle(), or null. Returns null when the argument carries no pointer.
- @p Source is the raw handle, raw buffer, wrapper, or null.
- @r A raw pointer carrier or null when no pointer is present.
getLib ()

Returns the opened native library for this generated wrapper.
- @r The opened native library.
handle ()

Returns the wrapped NativeHandle.
- @r The wrapped NativeHandle.
isNull ()

Returns true when the wrapped handle is null.
- @r A bool.
describe ()

Returns a small string for debugging generated wrappers.
- @r A string.
clear ()

Frees resources associated with a non-statically-allocated #GWeakRef. After this call, the #GWeakRef is left in an undefined state. You should only call this on a #GWeakRef that previously had g_weak_ref_init() called on it.
- @r None.
get ()

If @weak_ref is not empty, atomically acquire a strong reference to the object it points to, and return that reference. This function is needed because of the potential race between taking the pointer value and g_object_ref() on it, if the object was losing its last reference at the same time in a different thread. The caller should release the resulting reference in the usual way, by using g_object_unref().
- @r the object pointed to by @weak_ref, or %NULL if it was empty.
init (object object)

Initialise a non-statically-allocated #GWeakRef. This function also calls g_weak_ref_set() with @object on the freshly-initialised weak reference. This function should always be matched with a call to g_weak_ref_clear(). It is not necessary to use this function for a #GWeakRef in static storage because it will already be properly initialised. Just use g_weak_ref_set() directly.
- @p object is a #GObject or %NULL.
- @r None.
set (object object)

Change the object to which @weak_ref points, or set it to %NULL. You must own a strong reference on @object while calling this function.
- @p object is a #GObject or %NULL.
- @r None.