Type Aliases

The following type aliases are available globally.

  • Union of primitive glib values

    Declaration

    Swift

    public typealias GObjectTypeValueUnion = GObjectCHelpers.GObjectTypeValueUnion
  • A Void closure to use as a signal handler, that takes no parameters.

    Declaration

    Swift

    public typealias SignalHandler = () -> ()
  • A conversion closure transforming the first value into the second This closure needs to return true if successful, or false otherwise

    Declaration

    Swift

    public typealias ValueTransformer = (ValueRef, ValueRef) -> Bool
  • Internal type for SignalHandler closure holder

    Declaration

    Swift

    public typealias SignalHandlerClosureHolder = ClosureHolder<Void, Void>
  • Internal type for a binding closure holder

    Declaration

    Swift

    public typealias BindingClosureHolder = BindingHolder<ValueRef, ValueRef>
  • This is the signature of marshaller functions, required to marshall arrays of parameter values to signal emissions into C language callback invocations. It is merely an alias to GClosureMarshal since the GClosure mechanism takes over responsibility of actual function invocation for the signal system.

    Declaration

    Swift

    public typealias SignalCMarshaller = GSignalCMarshaller
  • A numerical value which represents the unique identifier of a registered type.

    Declaration

    Swift

    public typealias Type_ = GType
  • A callback function used by the type system to finalize those portions of a derived types class structure that were setup from the corresponding GBaseInitFunc() function. Class finalization basically works the inverse way in which class initialization is performed. See GClassInitFunc() for a discussion of the class initialization process.

    Declaration

    Swift

    public typealias BaseFinalizeFunc = GBaseFinalizeFunc
  • A callback function used by the type system to do base initialization of the class structures of derived types. It is called as part of the initialization process of all derived classes and should reallocate or reset all dynamic class members copied over from the parent class. For example, class members (such as strings) that are not sufficiently handled by a plain memory copy of the parent class into the derived class have to be altered. See GClassInitFunc() for a discussion of the class initialization process.

    Declaration

    Swift

    public typealias BaseInitFunc = GBaseInitFunc
  • A function to be called to transform from_value to to_value. If this is the transform_to function of a binding, then from_value is the source_property on the source object, and to_value is the target_property on the target object. If this is the transform_from function of a G_BINDING_BIDIRECTIONAL binding, then those roles are reversed.

    Declaration

    Swift

    public typealias BindingTransformFunc = GBindingTransformFunc
  • This function is provided by the user and should produce a copy of the passed in boxed structure.

    Declaration

    Swift

    public typealias BoxedCopyFunc = GBoxedCopyFunc
  • This function is provided by the user and should free the boxed structure passed.

    Declaration

    Swift

    public typealias BoxedFreeFunc = GBoxedFreeFunc
  • The type used for callback functions in structure definitions and function signatures. This doesn’t mean that all callback functions must take no parameters and return void. The required signature of a callback function is determined by the context in which is used (e.g. the signal to which it is connected). Use G_CALLBACK() to cast the callback function to a GCallback.

    Declaration

    Swift

    public typealias Callback = GCallback
  • A callback function used by the type system to finalize a class. This function is rarely needed, as dynamically allocated class resources should be handled by GBaseInitFunc() and GBaseFinalizeFunc(). Also, specification of a GClassFinalizeFunc() in the GTypeInfo structure of a static type is invalid, because classes of static types will never be finalized (they are artificially kept alive when their reference count drops to zero).

    Declaration

    Swift

    public typealias ClassFinalizeFunc = GClassFinalizeFunc
  • A callback function used by the type system to initialize the class of a specific type. This function should initialize all static class members.

    The initialization process of a class involves:

    • Copying common members from the parent class over to the derived class structure.
    • Zero initialization of the remaining members not copied over from the parent class.
    • Invocation of the GBaseInitFunc() initializers of all parent types and the class’ type.
    • Invocation of the class’ GClassInitFunc() initializer.

    Since derived classes are partially initialized through a memory copy of the parent class, the general rule is that GBaseInitFunc() and GBaseFinalizeFunc() should take care of necessary reinitialization and release of those class members that were introduced by the type that specified these GBaseInitFunc()/GBaseFinalizeFunc(). GClassInitFunc() should only care about initializing static class members, while dynamic class members (such as allocated strings or reference counted resources) are better handled by a GBaseInitFunc() for this type, so proper initialization of the dynamic class members is performed for class initialization of derived types as well.

    An example may help to correspond the intend of the different class initializers:

    (C Language Example):

    typedef struct {
      GObjectClass parent_class;
      gint         static_integer;
      gchar       *dynamic_string;
    } TypeAClass;
    static void
    type_a_base_class_init (TypeAClass *class)
    {
      class->dynamic_string = g_strdup ("some string");
    }
    static void
    type_a_base_class_finalize (TypeAClass *class)
    {
      g_free (class->dynamic_string);
    }
    static void
    type_a_class_init (TypeAClass *class)
    {
      class->static_integer = 42;
    }
    
    typedef struct {
      TypeAClass   parent_class;
      gfloat       static_float;
      GString     *dynamic_gstring;
    } TypeBClass;
    static void
    type_b_base_class_init (TypeBClass *class)
    {
      class->dynamic_gstring = g_string_new ("some other string");
    }
    static void
    type_b_base_class_finalize (TypeBClass *class)
    {
      g_string_free (class->dynamic_gstring);
    }
    static void
    type_b_class_init (TypeBClass *class)
    {
      class->static_float = 3.14159265358979323846;
    }
    

    Initialization of TypeBClass will first cause initialization of TypeAClass (derived classes reference their parent classes, see g_type_class_ref() on this).

    Initialization of TypeAClass roughly involves zero-initializing its fields, then calling its GBaseInitFunc() type_a_base_class_init() to allocate its dynamic members (dynamic_string), and finally calling its GClassInitFunc() type_a_class_init() to initialize its static members (static_integer). The first step in the initialization process of TypeBClass is then a plain memory copy of the contents of TypeAClass into TypeBClass and zero-initialization of the remaining fields in TypeBClass. The dynamic members of TypeAClass within TypeBClass now need reinitialization which is performed by calling type_a_base_class_init() with an argument of TypeBClass.

    After that, the GBaseInitFunc() of TypeBClass, type_b_base_class_init() is called to allocate the dynamic members of TypeBClass (dynamic_gstring), and finally the GClassInitFunc() of TypeBClass, type_b_class_init(), is called to complete the initialization process with the static members (static_float).

    Corresponding finalization counter parts to the GBaseInitFunc() functions have to be provided to release allocated resources at class finalization time.

    Declaration

    Swift

    public typealias ClassInitFunc = GClassInitFunc
  • The type used for marshaller functions.

    Declaration

    Swift

    public typealias ClosureMarshal = GClosureMarshal
  • The type used for the various notification callbacks which can be registered on closures.

    Declaration

    Swift

    public typealias ClosureNotify = GClosureNotify
  • A callback function used by the type system to initialize a new instance of a type. This function initializes all instance members and allocates any resources required by it.

    Initialization of a derived instance involves calling all its parent types instance initializers, so the class member of the instance is altered during its initialization to always point to the class that belongs to the type the current initializer was introduced for.

    The extended members of instance are guaranteed to have been filled with zeros before this function is called.

    Declaration

    Swift

    public typealias InstanceInitFunc = GInstanceInitFunc
  • A callback function used by the type system to finalize an interface. This function should destroy any internal data and release any resources allocated by the corresponding GInterfaceInitFunc() function.

    Declaration

    Swift

    public typealias InterfaceFinalizeFunc = GInterfaceFinalizeFunc
  • A callback function used by the type system to initialize a new interface. This function should initialize all internal data and allocate any resources required by the interface.

    The members of iface_data are guaranteed to have been filled with zeros before this function is called.

    Declaration

    Swift

    public typealias InterfaceInitFunc = GInterfaceInitFunc
  • The type of the finalize function of GObjectClass.

    Declaration

    Swift

    public typealias ObjectFinalizeFunc = GObjectFinalizeFunc
  • The type of the get_property function of GObjectClass.

    Declaration

    Swift

    public typealias ObjectGetPropertyFunc = GObjectGetPropertyFunc
  • The type of the set_property function of GObjectClass.

    Declaration

    Swift

    public typealias ObjectSetPropertyFunc = GObjectSetPropertyFunc
  • The signal accumulator is a special callback function that can be used to collect return values of the various callbacks that are called during a signal emission. The signal accumulator is specified at signal creation time, if it is left nil, no accumulation of callback return values is performed. The return value of signal emissions is then the value returned by the last callback.

    Declaration

    Swift

    public typealias SignalAccumulator = GSignalAccumulator
  • A simple function pointer to get invoked when the signal is emitted. This allows you to tie a hook to the signal type, so that it will trap all emissions of that signal, from any object.

    You may not attach these to signals created with the G_SIGNAL_NO_HOOKS flag.

    Declaration

    Swift

    public typealias SignalEmissionHook = GSignalEmissionHook
  • A callback function used for notification when the state of a toggle reference changes. See g_object_add_toggle_ref().

    Declaration

    Swift

    public typealias ToggleNotify = GToggleNotify
  • A callback function which is called when the reference count of a class drops to zero. It may use g_type_class_ref() to prevent the class from being freed. You should not call g_type_class_unref() from a GTypeClassCacheFunc function to prevent infinite recursion, use g_type_class_unref_uncached() instead.

    The functions have to check the class id passed in to figure whether they actually want to cache the class of this type, since all classes are routed through the same GTypeClassCacheFunc chain.

    Declaration

    Swift

    public typealias TypeClassCacheFunc = GTypeClassCacheFunc
  • A callback called after an interface vtable is initialized. See g_type_add_interface_check().

    Declaration

    Swift

    public typealias TypeInterfaceCheckFunc = GTypeInterfaceCheckFunc
  • The type of the complete_interface_info function of GTypePluginClass.

    Declaration

    Swift

    public typealias TypePluginCompleteInterfaceInfo = GTypePluginCompleteInterfaceInfo
  • The type of the complete_type_info function of GTypePluginClass.

    Declaration

    Swift

    public typealias TypePluginCompleteTypeInfo = GTypePluginCompleteTypeInfo
  • The type of the unuse_plugin function of GTypePluginClass.

    Declaration

    Swift

    public typealias TypePluginUnuse = GTypePluginUnuse
  • The type of the use_plugin function of GTypePluginClass, which gets called to increase the use count of plugin.

    Declaration

    Swift

    public typealias TypePluginUse = GTypePluginUse
  • The type of value transformation functions which can be registered with g_value_register_transform_func().

    dest_value will be initialized to the correct destination type.

    Declaration

    Swift

    public typealias ValueTransform = GValueTransform
  • A GWeakNotify function can be added to an object as a callback that gets triggered when the object is finalized. Since the object is already being finalized when the GWeakNotify is called, there’s not much you could do with the object, apart from e.g. using its address as hash-index or the like.

    Declaration

    Swift

    public typealias WeakNotify = GWeakNotify