QMetaProperty Class Reference

The QMetaProperty class provides meta-data about a property. More...

#include <qmetaobject.h>

Public Functions
const QMetaObject *	enclosingMetaObject () const
QMetaEnum	enumerator () const
	Returns the enumerator if this property's type is an enumerator type; otherwise the returned value is undefined. More...
bool	hasNotifySignal () const
	Returns true if this property has a corresponding change notify signal; otherwise returns false. More...
bool	hasStdCppSet () const
	Returns true if the property has a C++ setter function that follows Qt's standard "name" / "setName" pattern. More...
bool	isConstant () const
bool	isDesignable (const QObject *obj=0) const
	Returns true if this property is designable for the given object; otherwise returns false. More...
bool	isEditable (const QObject *obj=0) const
	Returns true if the property is constant; otherwise returns false. More...
bool	isEnumType () const
	Returns true if the property's type is an enumeration value; otherwise returns false. More...
bool	isFinal () const
bool	isFlagType () const
	Returns true if the property's type is an enumeration value that is used as a flag; otherwise returns false. More...
bool	isReadable () const
	Returns true if this property is readable; otherwise returns false. More...
bool	isResettable () const
	Returns true if this property can be reset to a default value; otherwise returns false. More...
bool	isScriptable (const QObject *obj=0) const
	Returns true if the property is scriptable for the given object; otherwise returns false. More...
bool	isStored (const QObject *obj=0) const
	Returns true if the property is stored for object; otherwise returns false. More...
bool	isUser (const QObject *obj=0) const
	Returns true if this property is designated as the USER property, i.e., the one that the user can edit for object or that is significant in some other way. More...
bool	isValid () const
	Returns true if this property is valid (readable); otherwise returns false. More...
bool	isWritable () const
	Returns true if this property is writable; otherwise returns false. More...
const char *	name () const
	Returns this property's name. More...
QMetaMethod	notifySignal () const
	Returns the QMetaMethod instance of the property change notifying signal if one was specified, otherwise returns an invalid QMetaMethod. More...
int	notifySignalIndex () const
	Returns the index of the property change notifying signal if one was specified, otherwise returns -1. More...
int	propertyIndex () const
	Returns this property's index. More...
	QMetaProperty ()
QVariant	read (const QObject *obj) const
	Reads the property's value from the given object. More...
bool	reset (QObject *obj) const
	Resets the property for the given object with a reset method. More...
int	revision () const
	Returns the property revision if one was specified by REVISION, otherwise returns 0. More...
QVariant::Type	type () const
	Returns this property's type. More...
const char *	typeName () const
	Returns the name of this property's type. More...
int	userType () const
	Returns this property's user type. More...
bool	write (QObject *obj, const QVariant &value) const
	Writes value as the property's value to the given object. More...

Properties
uint	handle
int	idx
QMetaEnum	menum
const QMetaObject *	mobj

Friends
struct	QMetaObject

Detailed Description

The QMetaProperty class provides meta-data about a property.

Property meta-data is obtained from an object's meta-object. See QMetaObject::property() and QMetaObject::propertyCount() for details.

Property Meta-Data

A property has a name() and a type(), as well as various attributes that specify its behavior: isReadable(), isWritable(), isDesignable(), isScriptable(), and isStored().

If the property is an enumeration, isEnumType() returns true; if the property is an enumeration that is also a flag (i.e. its values can be combined using the OR operator), isEnumType() and isFlagType() both return true. The enumerator for these types is available from enumerator().

The property's values are set and retrieved with read(), write(), and reset(); they can also be changed through QObject's set and get functions. See QObject::setProperty() and QObject::property() for details.

Copying and Assignment

QMetaProperty objects can be copied by value. However, each copy will refer to the same underlying property meta-data.

See also

QMetaObject, QMetaEnum, QMetaMethod, {Qt's Property System}

Definition at line 176 of file qmetaobject.h.

Constructors and Destructors

QMetaProperty()

QMetaProperty::QMetaProperty

(

)

Warning

This function is not part of the public interface.

Definition at line 2134 of file qmetaobject.cpp.

    : mobj(0), handle(0), idx(0)
{
}

Functions

enclosingMetaObject()

const QMetaObject * QMetaProperty::enclosingMetaObject ( ) const

inline

Warning

This function is not part of the public interface.

Definition at line 214 of file qmetaobject.h.

{ return mobj; }

enumerator()

QMetaEnum QMetaProperty::enumerator

(

)

const

Returns the enumerator if this property's type is an enumerator type; otherwise the returned value is undefined.

See also

isEnumType(), isFlagType()

Definition at line 2294 of file qmetaobject.cpp.

Referenced by QDeclarativeCompiler::genLiteralAssignment(), QDeclarativeCompiler::testLiteralAssignment(), QDeclarativeCompiler::testQualifiedEnumAssignment(), and QDeclarativePropertyPrivate::writeEnumProperty().

{
    return menum;
}

hasNotifySignal()

bool QMetaProperty::hasNotifySignal

(

)

const

Returns true if this property has a corresponding change notify signal; otherwise returns false.

See also

notifySignal()

Definition at line 2481 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativeVMEMetaObject::connectAlias(), QDeclarativeProperty::connectNotifySignal(), ShaderEffectItem::connectPropertySignals(), QDeclarativeBindingCompilerPrivate::fetch(), QDeclarativePropertyPrivate::findSignalByName(), QDeclarativeProperty::hasNotifySignal(), notifySignalIndex(), QDeclarativeEngineDebugService::propertyData(), and QDeclarativeWatchProxy::QDeclarativeWatchProxy().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    return flags & Notify;
}

hasStdCppSet()

bool QMetaProperty::hasStdCppSet

(

)

const

Returns true if the property has a C++ setter function that follows Qt's standard "name" / "setName" pattern.

Warning

This function is not part of the public interface.

Designer and uic query hasStdCppSet() in order to avoid expensive QObject::setProperty() calls. All properties in Qt [should] follow this pattern.

Definition at line 2279 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty().

{
    if (!mobj)
        return false;
    int handle = priv(mobj->d.data)->propertyData + 3*idx;
    int flags = mobj->d.data[handle + 2];
    return (flags & StdCppSet);
}

isConstant()

bool QMetaProperty::isConstant

(

)

const

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativePropertyCache::Data::flagsForProperty(), and QDeclarativeProperty::needsNotifySignal().

isDesignable()

bool QMetaProperty::isDesignable

(

const QObject *

object = 0

)

const

Returns true if this property is designable for the given object; otherwise returns false.

If no object is given, the function returns false if the )'s ;.

See also

isScriptable(), isStored()

Definition at line 2587 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativeProperty::isDesignable(), and QStyleSheetStyle::setProperties().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    bool b = flags & Designable;
    if (object) {
        void *argv[] = { &b };
        QMetaObject::metacall(const_cast<QObject*>(object), QMetaObject::QueryPropertyDesignable,
                              idx + mobj->propertyOffset(), argv);
    }
    return b;


}

isEditable()

bool QMetaProperty::isEditable

(

const QObject *

object = 0

)

const

Returns true if the property is constant; otherwise returns false.

Since

4.6

A property is constant if the <tt>)</tt>'s \c; const

{ if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Constant; }

/*!

Returns true if the property is final; otherwise returns false.

\since 4.6


A property is final if the <tt>)</tt>'s \c; const

{ if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Final; }

/*!

Returns true if the property is editable for the given \a object;
otherwise returns false.

If no \a object is given, the function returns false if the
<tt>)</tt>'s \c;.

\sa isDesignable(), isScriptable(), isStored()

Definition at line 2717 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    bool b = flags & Editable;
    if (object) {
        void *argv[] = { &b };
        QMetaObject::metacall(const_cast<QObject*>(object), QMetaObject::QueryPropertyEditable,
                              idx + mobj->propertyOffset(), argv);
    }
    return b;
}

isEnumType()

bool QMetaProperty::isEnumType

(

)

const

Returns true if the property's type is an enumeration value; otherwise returns false.

See also

enumerator(), isFlagType()

Definition at line 2258 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativeCompiler::compileAlias(), QScript::QtPropertyFunction::execute(), QDeclarativePropertyCache::Data::flagsForProperty(), QDeclarativeCompiler::genLiteralAssignment(), QAxBase::internalProperty(), isFlagType(), qax_generateDocumentation(), read(), QDeclarativeValueTypeScriptClass::setProperty(), QDeclarativeCompiler::testLiteralAssignment(), QDeclarativeCompiler::testQualifiedEnumAssignment(), type(), userType(), write(), and QDeclarativePropertyPrivate::writeEnumProperty().

{
    if (!mobj)
        return false;
    int handle = priv(mobj->d.data)->propertyData + 3*idx;
    int flags = mobj->d.data[handle + 2];
    return (flags & EnumOrFlag) && menum.name();
}

isFinal()

bool QMetaProperty::isFinal

(

)

const

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativeCompiler::buildDynamicMeta(), and QDeclarativeBindingCompilerPrivate::parseName().

isFlagType()

bool QMetaProperty::isFlagType

(

)

const

Returns true if the property's type is an enumeration value that is used as a flag; otherwise returns false.

Flags can be combined using the OR operator. A flag type is implicitly also an enum type.

See also

isEnumType(), enumerator(), QMetaEnum::isFlag()

Definition at line 2247 of file qmetaobject.cpp.

Referenced by QDeclarativeCompiler::genLiteralAssignment(), QDeclarativeCompiler::testLiteralAssignment(), QDeclarativeCompiler::testQualifiedEnumAssignment(), write(), and QDeclarativePropertyPrivate::writeEnumProperty().

{
    return isEnumType() && menum.isFlag();
}

isReadable()

bool QMetaProperty::isReadable

(

)

const

Returns true if this property is readable; otherwise returns false.

See also

isWritable(), read(), isValid()

Definition at line 2467 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), generateInterfaceXml(), QAxServerBase::Invoke(), QObject::property(), qax_generateDocumentation(), and readAllProperties().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    return flags & Readable;
}

isResettable()

bool QMetaProperty::isResettable

(

)

const

Returns true if this property can be reset to a default value; otherwise returns false.

See also

reset()

Definition at line 2454 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativePropertyCache::Data::flagsForProperty(), and reset().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    return flags & Resettable;
}

isScriptable()

bool QMetaProperty::isScriptable

(

const QObject *

object = 0

)

const

Returns true if the property is scriptable for the given object; otherwise returns false.

If no object is given, the function returns false if the )'s ;.

See also

isDesignable(), isStored()

Definition at line 2612 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativePropertyCache::append(), QDeclarativeEngineDebugService::buildObjectDump(), QDeclarativeCompiler::buildProperty(), QDeclarativeCompiler::buildValueTypeProperty(), QDeclarativeCompiler::compileAlias(), QDeclarativePropertyCache::create(), QScript::QObjectDelegate::deleteProperty(), QDeclarativeCompiler::doesPropertyExist(), QScript::QtPropertyFunction::execute(), generateInterfaceXml(), QScript::QObjectDelegate::getOwnPropertyDescriptor(), QScript::QObjectDelegate::getOwnPropertySlot(), QScript::isEnumerableMetaProperty(), QScript::QObjectDelegate::put(), qDBusPropertyGet(), readAllProperties(), and writeProperty().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    bool b = flags & Scriptable;
    if (object) {
        void *argv[] = { &b };
        QMetaObject::metacall(const_cast<QObject*>(object), QMetaObject::QueryPropertyScriptable,
                              idx + mobj->propertyOffset(), argv);
    }
    return b;
}

isStored()

bool QMetaProperty::isStored

(

const QObject *

object = 0

)

const

Returns true if the property is stored for object; otherwise returns false.

If no object is given, the function returns false if the )'s ;.

See also

isDesignable(), isScriptable()

Definition at line 2635 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    bool b = flags & Stored;
    if (object) {
        void *argv[] = { &b };
        QMetaObject::metacall(const_cast<QObject*>(object), QMetaObject::QueryPropertyStored,
                              idx + mobj->propertyOffset(), argv);
    }
    return b;
}

isUser()

bool QMetaProperty::isUser

(

const QObject *

object = 0

)

const

Returns true if this property is designated as the USER property, i.e., the one that the user can edit for object or that is significant in some other way.

Otherwise it returns false. e.g., the text property is the USER editable property of a QLineEdit.

If object is null, the function returns false if the {)}'s ;, isDesignable(), isScriptable()

Definition at line 2659 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), and QMetaObject::userProperty().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    bool b = flags & User;
    if (object) {
        void *argv[] = { &b };
        QMetaObject::metacall(const_cast<QObject*>(object), QMetaObject::QueryPropertyUser,
                              idx + mobj->propertyOffset(), argv);
    }
    return b;
}

isValid()

bool QMetaProperty::isValid ( ) const

inline

Returns true if this property is valid (readable); otherwise returns false.

See also

isReadable()

Definition at line 213 of file qmetaobject.h.

Referenced by QScript::QtPropertyFunction::execute(), QScript::QObjectDelegate::getOwnPropertyDescriptor(), QScript::QObjectDelegate::getOwnPropertySlot(), QAxBase::internalProperty(), and QScript::isEnumerableMetaProperty().

{ return isReadable(); }

isWritable()

bool QMetaProperty::isWritable

(

)

const

Returns true if this property is writable; otherwise returns false.

See also

isReadable(), write()

Definition at line 2569 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativeCompiler::buildGroupedProperty(), QDeclarativeCompiler::buildPropertyObjectAssignment(), QDeclarativeCompiler::buildPropertyOnAssignment(), QDeclarativeCompiler::compileAlias(), QScript::flagsForMetaProperty(), QDeclarativePropertyCache::Data::flagsForProperty(), generateInterfaceXml(), QScript::QObjectDelegate::getOwnPropertyDescriptor(), QAxServerBase::Invoke(), qax_generateDocumentation(), QDeclarativeValueTypeScriptClass::queryProperty(), QStyleSheetStyle::setProperties(), QObject::setProperty(), QDeclarativeCompiler::testLiteralAssignment(), QDeclarativeCompiler::testQualifiedEnumAssignment(), QPropertyAnimationPrivate::updateMetaProperty(), write(), and QDeclarativePropertyPrivate::writeEnumProperty().

{
    if (!mobj)
        return false;
    int flags = mobj->d.data[handle + 2];
    return flags & Writable;
}

name()

const char * QMetaProperty::name

(

)

const

Returns this property's name.

See also

type(), typeName()

Definition at line 2145 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativePropertyCache::append(), QDeclarativeCompiler::buildObject(), QDeclarativeCompiler::buildProperty(), QDeclarativeCompiler::doesPropertyExist(), QDeclarativeVisualDataModelPrivate::ensureRoles(), generateInterfaceXml(), QScript::QObjectDelegate::getOwnPropertyNames(), QAxBase::internalProperty(), QAxServerBase::Invoke(), QScript::isEnumerableMetaProperty(), QAxServerBase::Load(), QDataWidgetMapper::mappedPropertyName(), QDeclarativeProperty::name(), QDeclarativePropertyCache::Data::name(), QDBusAbstractInterfacePrivate::property(), QDeclarativeEngineDebugService::propertyChanged(), QDeclarativeEngineDebugService::propertyData(), QDeclarativeObjectScriptClass::propertyNames(), qax_generateDocumentation(), qax_noSuchFunction(), read(), readAllProperties(), QDeclarativeCompiledBindingsPrivate::run(), QAxServerBase::Save(), QStyledItemDelegate::setEditorData(), QItemDelegate::setEditorData(), QStyledItemDelegate::setModelData(), QItemDelegate::setModelData(), QDeclarativeCompiler::testLiteralAssignment(), QDeclarativeCompiler::testQualifiedEnumAssignment(), and QDeclarativeQtScriptExpression::updateGuards().

{
    if (!mobj)
        return 0;
    int handle = priv(mobj->d.data)->propertyData + 3*idx;
    return mobj->d.stringdata + mobj->d.data[handle];
}

notifySignal()

QMetaMethod QMetaProperty::notifySignal

(

)

const

Returns the QMetaMethod instance of the property change notifying signal if one was specified, otherwise returns an invalid QMetaMethod.

Since

4.5

See also

hasNotifySignal()

Definition at line 2500 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativeProperty::connectNotifySignal(), ShaderEffectItem::connectPropertySignals(), and QDeclarativePropertyPrivate::findSignalByName().

{
    int id = notifySignalIndex();
    if (id != -1)
        return mobj->method(id); 
    else
        return QMetaMethod();
}

notifySignalIndex()

int QMetaProperty::notifySignalIndex

(

)

const

Returns the index of the property change notifying signal if one was specified, otherwise returns -1.

Since

4.6

See also

hasNotifySignal()

Definition at line 2520 of file qmetaobject.cpp.

Referenced by QDeclarativeVMEMetaObject::connectAlias(), QDeclarativeProperty::connectNotifySignal(), QDeclarativeBindingCompilerPrivate::fetch(), QDeclarativePropertyCache::Data::load(), notifySignal(), and QDeclarativeWatchProxy::QDeclarativeWatchProxy().

{
    if (hasNotifySignal()) {
        int offset = priv(mobj->d.data)->propertyData +
                     priv(mobj->d.data)->propertyCount * 3 + idx;
        return mobj->d.data[offset] + mobj->methodOffset();
    } else {
        return -1;
    }
}

propertyIndex()

int QMetaProperty::propertyIndex

(

)

const

Returns this property's index.

Since

4.6

Definition at line 2230 of file qmetaobject.cpp.

Referenced by QDeclarativeCompiler::buildProperty(), QDeclarativeCompiler::genLiteralAssignment(), and QDeclarativePropertyCache::Data::load().

{
    if (!mobj)
        return -1;
    return idx + mobj->propertyOffset();
}

read()

QVariant QMetaProperty::read

(

const QObject *

object

)

const

Reads the property's value from the given object.

Returns the value if it was able to read it; otherwise returns an invalid variant.

See also

write(), reset(), isReadable()

Definition at line 2305 of file qmetaobject.cpp.

Referenced by QDeclarativeContext::contextProperty(), QScript::QtPropertyFunction::execute(), QDeclarativeCompiledBindingsPrivate::findproperty(), QScript::QObjectDelegate::getOwnPropertyDescriptor(), QScript::QObjectDelegate::getOwnPropertySlot(), QDeclarativeVisualDataModelDataMetaObject::initialValue(), QDeclarativeVMEMetaObject::metaCall(), QDeclarativeWatchProxy::notifyValueChanged(), QDeclarativeValueTypeScriptClass::property(), QDeclarativeObjectScriptClass::property(), QObject::property(), QDeclarativeEngineDebugService::propertyData(), qDBusPropertyGet(), readAllProperties(), and QDeclarativePropertyPrivate::readValueProperty().

{
    if (!object || !mobj)
        return QVariant();

    uint t = QVariant::Int;
    if (isEnumType()) {
        /*
          try to create a QVariant that can be converted to this enum
          type (only works if the enum has already been registered
          with QMetaType)
        */
        int enumMetaTypeId = QMetaType::type(qualifiedName(menum));
        if (enumMetaTypeId != 0)
            t = enumMetaTypeId;
    } else {
        int handle = priv(mobj->d.data)->propertyData + 3*idx;
        uint flags = mobj->d.data[handle + 2];
        const char *typeName = mobj->d.stringdata + mobj->d.data[handle + 1];
        t = (flags >> 24);
        if (t == 0xff) // special value for QVariant
            t = QVariant::LastType;
        if (t == QVariant::Invalid)
            t = QMetaType::type(typeName);
        if (t == QVariant::Invalid)
            t = QVariant::nameToType(typeName);
        if (t == QVariant::Invalid || t == QVariant::UserType) {
            if (t == QVariant::Invalid)
                qWarning("QMetaProperty::read: Unable to handle unregistered datatype '%s' for property '%s::%s'", typeName, mobj->className(), name());
            return QVariant();
        }
    }

    // the status variable is changed by qt_metacall to indicate what it did
    // this feature is currently only used by QtDBus and should not be depended
    // upon. Don't change it without looking into QDBusAbstractInterface first
    // -1 (unchanged): normal qt_metacall, result stored in argv[0]
    // changed: result stored directly in value
    int status = -1;
    QVariant value;
    void *argv[] = { 0, &value, &status };
    if (t == QVariant::LastType) {
        argv[0] = &value;
    } else {
        value = QVariant(t, (void*)0);
        argv[0] = value.data();
    }
    QMetaObject::metacall(const_cast<QObject*>(object), QMetaObject::ReadProperty,
                          idx + mobj->propertyOffset(), argv);

    if (status != -1)
        return value;
    if (t != QVariant::LastType && argv[0] != value.data())
        // pointer or reference
        return QVariant((QVariant::Type)t, argv[0]);
    return value;
}

reset()

bool QMetaProperty::reset

(

QObject *

object

)

const

Resets the property for the given object with a reset method.

Returns true if the reset worked; otherwise returns false.

Reset methods are optional; only a few properties support them.

See also

read(), write()

Definition at line 2439 of file qmetaobject.cpp.

{
    if (!object || !mobj || !isResettable())
        return false;
    void *argv[] = { 0 };
    QMetaObject::metacall(object, QMetaObject::ResetProperty, idx + mobj->propertyOffset(), argv);
    return true;
}

revision()

int QMetaProperty::revision

(

)

const

Returns the property revision if one was specified by REVISION, otherwise returns 0.

Warning

This function is not part of the public interface.

Definition at line 2540 of file qmetaobject.cpp.

Referenced by QDeclarativeBindingCompilerPrivate::fetch(), QDeclarativeTypePrivate::init(), and QDeclarativePropertyCache::Data::load().

{
    if (!mobj)
        return 0;
    int flags = mobj->d.data[handle + 2];
    if (flags & Revisioned) {
        int offset = priv(mobj->d.data)->propertyData +
                     priv(mobj->d.data)->propertyCount * 3 + idx;
        // Revision data is placed after NOTIFY data, if present.
        // Iterate through properties to discover whether we have NOTIFY signals.
        for (int i = 0; i < priv(mobj->d.data)->propertyCount; ++i) {
            int handle = priv(mobj->d.data)->propertyData + 3*i;
            if (mobj->d.data[handle + 2] & Notify) {
                offset += priv(mobj->d.data)->propertyCount;
                break;
            }
        }
        return mobj->d.data[offset];
    } else {
        return 0;
    }
}

type()

QVariant::Type QMetaProperty::type

(

)

const

Returns this property's type.

The return value is one of the values of the QVariant::Type enumeration.

See also

userType(), typeName(), name()

Definition at line 2172 of file qmetaobject.cpp.

Referenced by QDeclarativeCompiler::compileAlias(), QAxBase::internalProperty(), QAxEventSink::OnChanged(), QDBusAbstractInterfacePrivate::property(), QDeclarativeCompiler::testLiteralAssignment(), userType(), and writeProperty().

{
    if (!mobj)
        return QVariant::Invalid;
    int handle = priv(mobj->d.data)->propertyData + 3*idx;
    uint flags = mobj->d.data[handle + 2];

    uint type = flags >> 24;
    if (type == 0xff) // special value for QVariant
        type = QVariant::LastType;
    if (type)
        return QVariant::Type(type);
    if (isEnumType()) {
        int enumMetaTypeId = QMetaType::type(qualifiedName(menum));
        if (enumMetaTypeId == 0)
            return QVariant::Int;
    }
#ifdef QT_COORD_TYPE
    // qreal metatype must be resolved at runtime.
    if (strcmp(typeName(), "qreal") == 0)
        return QVariant::Type(qMetaTypeId<qreal>());
#endif

    return QVariant::UserType;
}

typeName()

const char * QMetaProperty::typeName

(

)

const

Returns the name of this property's type.

See also

type(), name()

Definition at line 2158 of file qmetaobject.cpp.

Referenced by QMetaObjectBuilder::addProperty(), QDeclarativeCompiler::compileAlias(), QAxBase::dynamicCallHelper(), QAxEventSink::findProperty(), generateInterfaceXml(), QAxBase::internalProperty(), QAxServerBase::Invoke(), QDBusAbstractInterfacePrivate::property(), QDeclarativeEngineDebugService::propertyData(), QDeclarativeProperty::propertyTypeName(), qax_generateDocumentation(), read(), readAllProperties(), QAxServerBase::Save(), type(), userType(), write(), and writeProperty().

{
    if (!mobj)
        return 0;
    int handle = priv(mobj->d.data)->propertyData + 3*idx;
    return mobj->d.stringdata + mobj->d.data[handle + 1];
}

userType()

int QMetaProperty::userType

(

)

const

Returns this property's user type.

Since

4.2

The return value is one of the values that are registered with QMetaType, or 0 if the type is not registered.

See also

type(), QMetaType, typeName()

Definition at line 2210 of file qmetaobject.cpp.

Referenced by QDeclarativeCompiler::buildProperty(), QDeclarativeCompiler::buildValueTypeProperty(), QScript::QtPropertyFunction::execute(), QDeclarativeBindingCompilerPrivate::fetch(), QDeclarativePropertyCache::Data::flagsForProperty(), QDeclarativeCompiler::genLiteralAssignment(), QDeclarativePropertyPrivate::initProperty(), QDeclarativePropertyCache::Data::load(), QDeclarativeVMEMetaObject::metaCall(), QDeclarativeWatchProxy::notifyValueChanged(), QDeclarativeEngineDebugService::propertyData(), QDeclarativePropertyPrivate::saveValueType(), QDeclarativeValueTypeScriptClass::setProperty(), and QDeclarativeCompiler::testLiteralAssignment().

{
    QVariant::Type tp = type();
    if (tp != QVariant::UserType)
        return tp;
    if (isEnumType()) {
        int enumMetaTypeId = QMetaType::type(qualifiedName(menum));
        return enumMetaTypeId;
    }
    return QMetaType::type(typeName());
}

write()

bool QMetaProperty::write	(	QObject *	object,
		const QVariant &	value
	)		const

Writes value as the property's value to the given object.

Returns true if the write succeeded; otherwise returns false.

See also

read(), reset(), isWritable()

Definition at line 2369 of file qmetaobject.cpp.

Referenced by QScript::QtPropertyFunction::execute(), QDeclarativeValueTypeScriptClass::setProperty(), QObject::setProperty(), and writeProperty().

{
    if (!object || !isWritable())
        return false;

    QVariant v = value;
    uint t = QVariant::Invalid;
    if (isEnumType()) {
        if (v.type() == QVariant::String
#ifdef QT3_SUPPORT
            || v.type() == QVariant::CString
#endif
            ) {
            if (isFlagType())
                v = QVariant(menum.keysToValue(value.toByteArray()));
            else
                v = QVariant(menum.keyToValue(value.toByteArray()));
        } else if (v.type() != QVariant::Int && v.type() != QVariant::UInt) {
            int enumMetaTypeId = QMetaType::type(qualifiedName(menum));
            if ((enumMetaTypeId == 0) || (v.userType() != enumMetaTypeId) || !v.constData())
                return false;
            v = QVariant(*reinterpret_cast<const int *>(v.constData()));
        }
        v.convert(QVariant::Int);
    } else {
        int handle = priv(mobj->d.data)->propertyData + 3*idx;
        uint flags = mobj->d.data[handle + 2];
        t = flags >> 24;
        if (t == 0xff) // special value for QVariant
            t = QVariant::LastType;
        if (t == QVariant::Invalid) {
            const char *typeName = mobj->d.stringdata + mobj->d.data[handle + 1];
            const char *vtypeName = value.typeName();
            if (vtypeName && strcmp(typeName, vtypeName) == 0)
                t = value.userType();
            else
                t = QVariant::nameToType(typeName);
        }
        if (t == QVariant::Invalid)
            return false;
        if (t != QVariant::LastType && t != (uint)value.userType() && (t < QMetaType::User && !v.convert((QVariant::Type)t)))
            return false;
    }

    // the status variable is changed by qt_metacall to indicate what it did
    // this feature is currently only used by QtDBus and should not be depended
    // upon. Don't change it without looking into QDBusAbstractInterface first
    // -1 (unchanged): normal qt_metacall, result stored in argv[0]
    // changed: result stored directly in value, return the value of status
    int status = -1;
    // the flags variable is used by the declarative module to implement
    // interception of property writes.
    int flags = 0;
    void *argv[] = { 0, &v, &status, &flags };
    if (t == QVariant::LastType)
        argv[0] = &v;
    else
        argv[0] = v.data();
    QMetaObject::metacall(object, QMetaObject::WriteProperty, idx + mobj->propertyOffset(), argv);
    return status;
}

Friends and Related Functions

QMetaObject

friend struct QMetaObject

friend

Definition at line 221 of file qmetaobject.h.

Properties

handle

uint QMetaProperty::handle

private

Definition at line 218 of file qmetaobject.h.

Referenced by hasNotifySignal(), hasStdCppSet(), isDesignable(), isEnumType(), isReadable(), isResettable(), isScriptable(), isStored(), isUser(), isWritable(), name(), QMetaObject::property(), read(), revision(), type(), typeName(), and write().

idx

int QMetaProperty::idx

private

Definition at line 219 of file qmetaobject.h.

Referenced by hasStdCppSet(), isDesignable(), isEnumType(), isScriptable(), isStored(), isUser(), name(), notifySignalIndex(), QMetaObject::property(), propertyIndex(), read(), reset(), revision(), type(), typeName(), and write().

menum

QMetaEnum QMetaProperty::menum

private

Definition at line 220 of file qmetaobject.h.

Referenced by enumerator(), isEnumType(), isFlagType(), QMetaObject::property(), read(), type(), userType(), and write().

mobj

const QMetaObject* QMetaProperty::mobj

private

Definition at line 217 of file qmetaobject.h.

Referenced by hasNotifySignal(), hasStdCppSet(), isDesignable(), isEnumType(), isReadable(), isResettable(), isScriptable(), isStored(), isUser(), isWritable(), name(), notifySignal(), notifySignalIndex(), QMetaObject::property(), propertyIndex(), read(), reset(), revision(), type(), typeName(), and write().

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The documentation for this class was generated from the following files:

• /src/corelib/kernel/qmetaobject.h
• /src/corelib/kernel/qmetaobject.cpp