Struct
GObjectValue
Description [src]
struct GValue {
None data;
}
An opaque structure used to hold different types of values.
Before it can be used, a GValue has to be initialized to a specific type by
calling g_value_init() on it.
Many types which are stored within a GValue need to allocate data on the
heap, so g_value_unset() must always be called on a GValue to
free any such data once you’re finished with the GValue, even if the
GValue itself is stored on the stack.
The data within the structure has protected scope: it is accessible only
to functions within a GTypeValueTable structure, or
implementations of the g_value_*() API. That is, code which implements new
fundamental types.
GValue users cannot make any assumptions about how data is stored
within the 2 element data union, and the g_type member should
only be accessed through the G_VALUE_TYPE() macro and related macros.
Structure members
dataNo description available.
Functions
g_value_register_transform_func
Registers a value transformation function for use in
g_value_transform().
g_value_type_compatible
Checks whether a g_value_copy() is able to copy values of type
src_type into values of type dest_type.
g_value_type_transformable
Checks whether g_value_transform() is able to transform values
of type src_type into values of type dest_type.
Instance methods
g_value_dup_boxed
Get the contents of a G_TYPE_BOXED derived GValue. Upon getting,
the boxed value is duplicated and needs to be later freed with
g_boxed_free(), e.g. like: g_boxed_free (G_VALUE_TYPE (value), return_value);.
g_value_dup_object
Get the contents of a G_TYPE_OBJECT derived GValue, increasing
its reference count. If the contents of the GValue are NULL, then
NULL will be returned.
g_value_dup_variant
Get the contents of a variant GValue, increasing its refcount. The returned
GVariant is never floating.
since: 2.26
g_value_get_char
Do not use this function; it is broken on platforms where the %char type is unsigned, such as ARM and PowerPC. See g_value_get_schar().
deprecated: 2.32
g_value_init
Initializes value to store values of the given type, and sets its value
to the default for type.
g_value_reset
Clears the current value in value and resets it to the default value
(as if the value had just been initialized using
g_value_init()).
g_value_set_boxed_take_ownership
This is an internal function introduced mainly for C marshallers.
deprecated: 2.4
g_value_set_interned_string
Set the contents of a G_TYPE_STRING GValue to v_string. The string is
assumed to be static and interned (canonical, for example from
g_intern_string()), and is thus not duplicated when setting the GValue.
since: 2.66
g_value_set_object_take_ownership
This is an internal function introduced mainly for C marshallers.
deprecated: 2.4
g_value_set_param_take_ownership
This is an internal function introduced mainly for C marshallers.
deprecated: 2.4
g_value_set_static_string
Set the contents of a G_TYPE_STRING GValue to v_string.
The string is assumed to be static, and is thus not duplicated
when setting the GValue.
g_value_set_string_take_ownership
This is an internal function introduced mainly for C marshallers.
deprecated: 2.4
g_value_set_variant
Set the contents of a variant GValue to variant.
If the variant is floating, it is consumed.
since: 2.26
g_value_steal_string
Steal ownership on contents of a G_TYPE_STRING GValue.
As a result of this operation the value’s contents will be reset to NULL.
since: 2.80
g_value_take_boxed
Sets the contents of a G_TYPE_BOXED derived GValue to v_boxed
and takes over the ownership of the caller’s reference to v_boxed;
the caller doesn’t have to unref it any more.
since: 2.4
g_value_take_object
Sets the contents of a G_TYPE_OBJECT derived GValue to v_object
and takes over the ownership of the caller’s reference to v_object;
the caller doesn’t have to unref it any more (i.e. the reference
count of the object is not increased).
since: 2.4
g_value_take_param
Sets the contents of a G_TYPE_PARAM GValue to param and takes
over the ownership of the caller’s reference to param; the caller
doesn’t have to unref it any more.
since: 2.4
g_value_take_variant
Set the contents of a variant GValue to variant, and takes over
the ownership of the caller’s reference to variant;
the caller doesn’t have to unref it any more (i.e. the reference
count of the variant is not increased).
since: 2.26
g_value_transform
Tries to cast the contents of src_value into a type appropriate
to store in dest_value.