Value

The GValue structure is basically a variable container that consists of a type identifier and a specific value of that type. The type identifier within a GValue structure always determines the type of the associated value. To create a undefined GValue structure, simply create a zero-filled GValue structure. To initialize the GValue, use the g_value_init() function. A GValue cannot be used until it is initialized. The basic type operations (such as freeing and copying) are determined by the GTypeValueTable associated with the type ID stored in the GValue. Other GValue operations (such as converting values between types) are provided by this interface.

The code in the example program below demonstrates GValue's features.

class Value {

GValue* gValue;

GValue* getValueStruct();

void* getStruct();

this(GValue* gValue);

this(Pixbuf pixbuf);

this(string value);

this(int value);

this(float value);

this(double value);

Value init(GType gType);

Value reset();

void copy(Value destValue);

void unset();

void setInstance(void* instanc);

int fitsPointer();

void* peekPointer();

static int typeCompatible(GType srcType, GType destType);

static int typeTransformable(GType srcType, GType destType);

int transform(Value destValue);

static void registerTransformFunc(GType srcType, GType destType, GValueTransform transformFunc);

string gStrdupValueContents();

static ParamSpec gParamSpecBoolean(string name, string nick, string blurb, int defaultValue, GParamFlags flags);

void setBoolean(int vBoolean);

int getBoolean();

static ParamSpec gParamSpecChar(string name, string nick, string blurb, byte minimum, byte maximum, byte defaultValue, GParamFlags flags);

void setChar(char vChar);

char getChar();

byte getSchar();

void setSchar(byte vChar);

static ParamSpec gParamSpecUchar(string name, string nick, string blurb, ubyte minimum, ubyte maximum, ubyte defaultValue, GParamFlags flags);

void setUchar(char vUchar);

char getUchar();

static ParamSpec gParamSpecInt(string name, string nick, string blurb, int minimum, int maximum, int defaultValue, GParamFlags flags);

void setInt(int vInt);

int getInt();

static ParamSpec gParamSpecUint(string name, string nick, string blurb, uint minimum, uint maximum, uint defaultValue, GParamFlags flags);

void setUint(uint vUint);

uint getUint();

static ParamSpec gParamSpecLong(string name, string nick, string blurb, glong minimum, glong maximum, glong defaultValue, GParamFlags flags);

void setLong(glong vLong);

glong getLong();

static ParamSpec gParamSpecUlong(string name, string nick, string blurb, gulong minimum, gulong maximum, gulong defaultValue, GParamFlags flags);

void setUlong(gulong vUlong);

gulong getUlong();

static ParamSpec gParamSpecInt64(string name, string nick, string blurb, long minimum, long maximum, long defaultValue, GParamFlags flags);

void setInt64(long vInt64);

long getInt64();

static ParamSpec gParamSpecUint64(string name, string nick, string blurb, ulong minimum, ulong maximum, ulong defaultValue, GParamFlags flags);

void setUint64(ulong vUint64);

ulong getUint64();

static ParamSpec gParamSpecFloat(string name, string nick, string blurb, float minimum, float maximum, float defaultValue, GParamFlags flags);

void setFloat(float vFloat);

float getFloat();

static ParamSpec gParamSpecDouble(string name, string nick, string blurb, double minimum, double maximum, double defaultValue, GParamFlags flags);

void setDouble(double vDouble);

double getDouble();

static ParamSpec gParamSpecEnum(string name, string nick, string blurb, GType enumType, int defaultValue, GParamFlags flags);

void setEnum(int vEnum);

int getEnum();

static ParamSpec gParamSpecFlags(string name, string nick, string blurb, GType flagsType, uint defaultValue, GParamFlags flags);

void setFlags(uint vFlags);

uint getFlags();

static ParamSpec gParamSpecString(string name, string nick, string blurb, string defaultValue, GParamFlags flags);

void setString(string vString);

void setStaticString(string vString);

void takeString(string vString);

void setStringTakeOwnership(string vString);

string getString();

string dupString();

static ParamSpec gParamSpecParam(string name, string nick, string blurb, GType paramType, GParamFlags flags);

void setParam(ParamSpec param);

void takeParam(ParamSpec param);

void setParamTakeOwnership(ParamSpec param);

ParamSpec getParam();

ParamSpec dupParam();

static ParamSpec gParamSpecBoxed(string name, string nick, string blurb, GType boxedType, GParamFlags flags);

void setBoxed(void* vBoxed);

void setStaticBoxed(void* vBoxed);

void takeBoxed(void* vBoxed);

void setBoxedTakeOwnership(void* vBoxed);

void* getBoxed();

void* dupBoxed();

static ParamSpec gParamSpecPointer(string name, string nick, string blurb, GParamFlags flags);

void setPointer(void* vPointer);

void* getPointer();

static ParamSpec gParamSpecObject(string name, string nick, string blurb, GType objectType, GParamFlags flags);

void setObject(void* vObject);

void takeObject(void* vObject);

void setObjectTakeOwnership(void* vObject);

void* getObject();

void* dupObject();

static ParamSpec gParamSpecUnichar(string name, string nick, string blurb, gunichar defaultValue, GParamFlags flags);

static ParamSpec gParamSpecValueArray(string name, string nick, string blurb, ParamSpec elementSpec, GParamFlags flags);

static ParamSpec gParamSpecOverride(string name, ParamSpec overridden);

static ParamSpec gParamSpecGtype(string name, string nick, string blurb, GType isAType, GParamFlags flags);

GType getGtype();

void setGtype(GType vGtype);

static ParamSpec gParamSpecVariant(string name, string nick, string blurb, VariantType type, Variant defaultValue, GParamFlags flags);

Variant getVariant();

Variant dupVariant();

void setVariant(Variant variant);

void takeVariant(Variant variant);

}

Constructors

this this(GValue* gValue): Sets our main struct and passes it to the parent class
this this()
this this(Pixbuf pixbuf)
this this(string value)
this this(int value)
this this(float value)
this this(double value)

Members

Functions

copy void copy(Value destValue): Copies the value of src_value into dest_value.
dupBoxed void* dupBoxed(): 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);
dupObject void* dupObject(): 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.
dupParam ParamSpec dupParam(): Get the contents of a G_TYPE_PARAM GValue, increasing its reference count.
dupString string dupString(): Get a copy the contents of a G_TYPE_STRING GValue.
dupVariant Variant dupVariant(): Get the contents of a variant GValue, increasing its refcount. Since 2.26
fitsPointer int fitsPointer(): Determines if value will fit inside the size of a pointer value. This is an internal function introduced mainly for C marshallers.
gStrdupValueContents string gStrdupValueContents(): Return a newly allocated string, which describes the contents of a GValue. The main purpose of this function is to describe GValue contents for debugging output, the way in which the contents are described may change between different GLib versions.
getBoolean int getBoolean(): Get the contents of a G_TYPE_BOOLEAN GValue.
getBoxed void* getBoxed(): Get the contents of a G_TYPE_BOXED derived GValue.
getChar char getChar(): Warning g_value_get_char has been deprecated since version 2.32 and should not be used in newly-written code. This function's return type is broken, see g_value_get_schar() 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(). Get the contents of a G_TYPE_CHAR GValue.
getDouble double getDouble(): Get the contents of a G_TYPE_DOUBLE GValue.
getEnum int getEnum(): Get the contents of a G_TYPE_ENUM GValue.
getFlags uint getFlags(): Get the contents of a G_TYPE_FLAGS GValue.
getFloat float getFloat(): Get the contents of a G_TYPE_FLOAT GValue.
getGtype GType getGtype(): Get the contents of a G_TYPE_GTYPE GValue. Since 2.12
getInt int getInt(): Get the contents of a G_TYPE_INT GValue.
getInt64 long getInt64(): Get the contents of a G_TYPE_INT64 GValue.
getLong glong getLong(): Get the contents of a G_TYPE_LONG GValue.
getObject void* getObject(): Get the contents of a G_TYPE_OBJECT derived GValue.
getParam ParamSpec getParam(): Get the contents of a G_TYPE_PARAM GValue.
getPointer void* getPointer(): Get the contents of a pointer GValue.
getSchar byte getSchar(): Get the contents of a G_TYPE_CHAR GValue. Since 2.32
getString string getString(): Get the contents of a G_TYPE_STRING GValue.
getStruct void* getStruct(): the main Gtk struct as a void*
getUchar char getUchar(): Get the contents of a G_TYPE_UCHAR GValue.
getUint uint getUint(): Get the contents of a G_TYPE_UINT GValue.
getUint64 ulong getUint64(): Get the contents of a G_TYPE_UINT64 GValue.
getUlong gulong getUlong(): Get the contents of a G_TYPE_ULONG GValue.
getValueStruct GValue* getValueStruct(): Undocumented in source. Be warned that the author may not have intended to support it.
getVariant Variant getVariant(): Get the contents of a variant GValue. Since 2.26
init Value init(GType gType): Initializes value with the default value of type.
peekPointer void* peekPointer()
reset Value reset(): Clears the current value in value and resets it to the default value (as if the value had just been initialized).
setBoolean void setBoolean(int vBoolean): Set the contents of a G_TYPE_BOOLEAN GValue to v_boolean.
setBoxed void setBoxed(void* vBoxed): Set the contents of a G_TYPE_BOXED derived GValue to v_boxed.
setBoxedTakeOwnership void setBoxedTakeOwnership(void* vBoxed): Warning g_value_set_boxed_take_ownership has been deprecated since version 2.4 and should not be used in newly-written code. Use g_value_take_boxed() instead. This is an internal function introduced mainly for C marshallers.
setChar void setChar(char vChar): Warning g_value_set_char has been deprecated since version 2.32 and should not be used in newly-written code. This function's input type is broken, see g_value_set_schar() Set the contents of a G_TYPE_CHAR GValue to v_char.
setDouble void setDouble(double vDouble): Set the contents of a G_TYPE_DOUBLE GValue to v_double.
setEnum void setEnum(int vEnum): Set the contents of a G_TYPE_ENUM GValue to v_enum.
setFlags void setFlags(uint vFlags): Set the contents of a G_TYPE_FLAGS GValue to v_flags.
setFloat void setFloat(float vFloat): Set the contents of a G_TYPE_FLOAT GValue to v_float.
setGtype void setGtype(GType vGtype): Set the contents of a G_TYPE_GTYPE GValue to v_gtype. Since 2.12
setInstance void setInstance(void* instanc): Sets value from an instantiatable type via the value_table's collect_value() function.
setInt void setInt(int vInt): Set the contents of a G_TYPE_INT GValue to v_int.
setInt64 void setInt64(long vInt64): Set the contents of a G_TYPE_INT64 GValue to v_int64.
setLong void setLong(glong vLong): Set the contents of a G_TYPE_LONG GValue to v_long.
setObject void setObject(void* vObject): Set the contents of a G_TYPE_OBJECT derived GValue to v_object. g_value_set_object() increases the reference count of v_object (the GValue holds a reference to v_object). If you do not wish to increase the reference count of the object (i.e. you wish to pass your current reference to the GValue because you no longer need it), use g_value_take_object() instead. It is important that your GValue holds a reference to v_object (either its own, or one it has taken) to ensure that the object won't be destroyed while the GValue still exists).
setObjectTakeOwnership void setObjectTakeOwnership(void* vObject): Warning g_value_set_object_take_ownership has been deprecated since version 2.4 and should not be used in newly-written code. Use g_value_take_object() instead. This is an internal function introduced mainly for C marshallers.
setParam void setParam(ParamSpec param): Set the contents of a G_TYPE_PARAM GValue to param.
setParamTakeOwnership void setParamTakeOwnership(ParamSpec param): Warning g_value_set_param_take_ownership has been deprecated since version 2.4 and should not be used in newly-written code. Use g_value_take_param() instead. This is an internal function introduced mainly for C marshallers.
setPointer void setPointer(void* vPointer): Set the contents of a pointer GValue to v_pointer.
setSchar void setSchar(byte vChar): Set the contents of a G_TYPE_CHAR GValue to v_char. Since 2.32
setStaticBoxed void setStaticBoxed(void* vBoxed): Set the contents of a G_TYPE_BOXED derived GValue to v_boxed. The boxed value is assumed to be static, and is thus not duplicated when setting the GValue.
setStaticString void setStaticString(string vString): 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.
setString void setString(string vString): Set the contents of a G_TYPE_STRING GValue to v_string.
setStringTakeOwnership void setStringTakeOwnership(string vString): Warning g_value_set_string_take_ownership has been deprecated since version 2.4 and should not be used in newly-written code. Use g_value_take_string() instead. This is an internal function introduced mainly for C marshallers.
setUchar void setUchar(char vUchar): Set the contents of a G_TYPE_UCHAR GValue to v_uchar.
setUint void setUint(uint vUint): Set the contents of a G_TYPE_UINT GValue to v_uint.
setUint64 void setUint64(ulong vUint64): Set the contents of a G_TYPE_UINT64 GValue to v_uint64.
setUlong void setUlong(gulong vUlong): Set the contents of a G_TYPE_ULONG GValue to v_ulong.
setVariant void setVariant(Variant variant): Set the contents of a variant GValue to variant. If the variant is floating, it is consumed. Since 2.26
takeBoxed void takeBoxed(void* vBoxed): Sets the contents of a G_TYPE_BOXED derived GValue to v_boxed and takes over the ownership of the callers reference to v_boxed; the caller doesn't have to unref it any more. Since 2.4
takeObject void takeObject(void* vObject): Sets the contents of a G_TYPE_OBJECT derived GValue to v_object and takes over the ownership of the callers 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). If you want the GValue to hold its own reference to v_object, use g_value_set_object() instead. Since 2.4
takeParam void takeParam(ParamSpec param): Sets the contents of a G_TYPE_PARAM GValue to param and takes over the ownership of the callers reference to param; the caller doesn't have to unref it any more. Since 2.4
takeString void takeString(string vString): Sets the contents of a G_TYPE_STRING GValue to v_string. Since 2.4
takeVariant void takeVariant(Variant 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). If variant was floating then its floating reference is converted to a hard reference. If you want the GValue to hold its own reference to variant, use g_value_set_variant() instead. This is an internal function introduced mainly for C marshallers. Since 2.26
transform int transform(Value destValue): Tries to cast the contents of src_value into a type appropriate to store in dest_value, e.g. to transform a G_TYPE_INT value into a G_TYPE_FLOAT value. Performing transformations between value types might incur precision lossage. Especially transformations into strings might reveal seemingly arbitrary results and shouldn't be relied upon for production code (such as rcfile value or object property serialization).
unset void unset(): Clears the current value in value and "unsets" the type, this releases all resources associated with this GValue. An unset value is the same as an uninitialized (zero-filled) GValue structure.

Static functions

gParamSpecBoolean ParamSpec gParamSpecBoolean(string name, string nick, string blurb, int defaultValue, GParamFlags flags): Creates a new GParamSpecBoolean instance specifying a G_TYPE_BOOLEAN property. See g_param_spec_internal() for details on property names.
gParamSpecBoxed ParamSpec gParamSpecBoxed(string name, string nick, string blurb, GType boxedType, GParamFlags flags): Creates a new GParamSpecBoxed instance specifying a G_TYPE_BOXED derived property. See g_param_spec_internal() for details on property names.
gParamSpecChar ParamSpec gParamSpecChar(string name, string nick, string blurb, byte minimum, byte maximum, byte defaultValue, GParamFlags flags): Creates a new GParamSpecChar instance specifying a G_TYPE_CHAR property.
gParamSpecDouble ParamSpec gParamSpecDouble(string name, string nick, string blurb, double minimum, double maximum, double defaultValue, GParamFlags flags): Creates a new GParamSpecDouble instance specifying a G_TYPE_DOUBLE property. See g_param_spec_internal() for details on property names.
gParamSpecEnum ParamSpec gParamSpecEnum(string name, string nick, string blurb, GType enumType, int defaultValue, GParamFlags flags): Creates a new GParamSpecEnum instance specifying a G_TYPE_ENUM property. See g_param_spec_internal() for details on property names.
gParamSpecFlags ParamSpec gParamSpecFlags(string name, string nick, string blurb, GType flagsType, uint defaultValue, GParamFlags flags): Creates a new GParamSpecFlags instance specifying a G_TYPE_FLAGS property. See g_param_spec_internal() for details on property names.
gParamSpecFloat ParamSpec gParamSpecFloat(string name, string nick, string blurb, float minimum, float maximum, float defaultValue, GParamFlags flags): Creates a new GParamSpecFloat instance specifying a G_TYPE_FLOAT property. See g_param_spec_internal() for details on property names.
gParamSpecGtype ParamSpec gParamSpecGtype(string name, string nick, string blurb, GType isAType, GParamFlags flags): Creates a new GParamSpecGType instance specifying a G_TYPE_GTYPE property. See g_param_spec_internal() for details on property names. Since 2.10
gParamSpecInt ParamSpec gParamSpecInt(string name, string nick, string blurb, int minimum, int maximum, int defaultValue, GParamFlags flags): Creates a new GParamSpecInt instance specifying a G_TYPE_INT property. See g_param_spec_internal() for details on property names.
gParamSpecInt64 ParamSpec gParamSpecInt64(string name, string nick, string blurb, long minimum, long maximum, long defaultValue, GParamFlags flags): Creates a new GParamSpecInt64 instance specifying a G_TYPE_INT64 property. See g_param_spec_internal() for details on property names.
gParamSpecLong ParamSpec gParamSpecLong(string name, string nick, string blurb, glong minimum, glong maximum, glong defaultValue, GParamFlags flags): Creates a new GParamSpecLong instance specifying a G_TYPE_LONG property. See g_param_spec_internal() for details on property names.
gParamSpecObject ParamSpec gParamSpecObject(string name, string nick, string blurb, GType objectType, GParamFlags flags): Creates a new GParamSpecBoxed instance specifying a G_TYPE_OBJECT derived property. See g_param_spec_internal() for details on property names.
gParamSpecOverride ParamSpec gParamSpecOverride(string name, ParamSpec overridden): Creates a new property of type GParamSpecOverride. This is used to direct operations to another paramspec, and will not be directly useful unless you are implementing a new base type similar to GObject. Since 2.4
gParamSpecParam ParamSpec gParamSpecParam(string name, string nick, string blurb, GType paramType, GParamFlags flags): Creates a new GParamSpecParam instance specifying a G_TYPE_PARAM property. See g_param_spec_internal() for details on property names.
gParamSpecPointer ParamSpec gParamSpecPointer(string name, string nick, string blurb, GParamFlags flags): Creates a new GParamSpecPointer instance specifying a pointer property. See g_param_spec_internal() for details on property names.
gParamSpecString ParamSpec gParamSpecString(string name, string nick, string blurb, string defaultValue, GParamFlags flags): Creates a new GParamSpecString instance. See g_param_spec_internal() for details on property names.
gParamSpecUchar ParamSpec gParamSpecUchar(string name, string nick, string blurb, ubyte minimum, ubyte maximum, ubyte defaultValue, GParamFlags flags): Creates a new GParamSpecUChar instance specifying a G_TYPE_UCHAR property.
gParamSpecUint ParamSpec gParamSpecUint(string name, string nick, string blurb, uint minimum, uint maximum, uint defaultValue, GParamFlags flags): Creates a new GParamSpecUInt instance specifying a G_TYPE_UINT property. See g_param_spec_internal() for details on property names.
gParamSpecUint64 ParamSpec gParamSpecUint64(string name, string nick, string blurb, ulong minimum, ulong maximum, ulong defaultValue, GParamFlags flags): Creates a new GParamSpecUInt64 instance specifying a G_TYPE_UINT64 property. See g_param_spec_internal() for details on property names.
gParamSpecUlong ParamSpec gParamSpecUlong(string name, string nick, string blurb, gulong minimum, gulong maximum, gulong defaultValue, GParamFlags flags): Creates a new GParamSpecULong instance specifying a G_TYPE_ULONG property. See g_param_spec_internal() for details on property names.
gParamSpecUnichar ParamSpec gParamSpecUnichar(string name, string nick, string blurb, gunichar defaultValue, GParamFlags flags): Creates a new GParamSpecUnichar instance specifying a G_TYPE_UINT property. GValue structures for this property can be accessed with g_value_set_uint() and g_value_get_uint(). See g_param_spec_internal() for details on property names.
gParamSpecValueArray ParamSpec gParamSpecValueArray(string name, string nick, string blurb, ParamSpec elementSpec, GParamFlags flags): Creates a new GParamSpecValueArray instance specifying a G_TYPE_VALUE_ARRAY property. G_TYPE_VALUE_ARRAY is a G_TYPE_BOXED type, as such, GValue structures for this property can be accessed with g_value_set_boxed() and g_value_get_boxed(). See g_param_spec_internal() for details on property names.
gParamSpecVariant ParamSpec gParamSpecVariant(string name, string nick, string blurb, VariantType type, Variant defaultValue, GParamFlags flags): Creates a new GParamSpecVariant instance specifying a GVariant property. If default_value is floating, it is consumed. See g_param_spec_internal() for details on property names. Since 2.26
registerTransformFunc void registerTransformFunc(GType srcType, GType destType, GValueTransform transformFunc): Registers a value transformation function for use in g_value_transform(). A previously registered transformation function for src_type and dest_type will be replaced.
typeCompatible int typeCompatible(GType srcType, GType destType): Returns whether a GValue of type src_type can be copied into a GValue of type dest_type.
typeTransformable int typeTransformable(GType srcType, GType destType): Check whether g_value_transform() is able to transform values of type src_type into values of type dest_type.

Variables

gValue GValue* gValue;: the main Gtk struct

Meta

Source

See Implementation

gobject Value classes

Value