/**************************************************************************** ** ** Copyright (C) 2015 The Qt Company Ltd. ** Contact: http://www.qt.io/licensing/ ** ** This file is part of the QtQml module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL21$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see http://www.qt.io/terms-conditions. For further ** information use the contact form at http://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 or version 3 as published by the Free ** Software Foundation and appearing in the file LICENSE.LGPLv21 and ** LICENSE.LGPLv3 included in the packaging of this file. Please review the ** following information to ensure the GNU Lesser General Public License ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** As a special exception, The Qt Company gives you certain additional ** rights. These rights are described in The Qt Company LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qqmlproperty.h" #include "qqmlproperty_p.h" #include "qqml.h" #include "qqmlbinding_p.h" #include "qqmlcontext.h" #include "qqmlcontext_p.h" #include "qqmlboundsignal_p.h" #include "qqmlengine.h" #include "qqmlengine_p.h" #include "qqmldata_p.h" #include "qqmlstringconverters_p.h" #include "qqmllist_p.h" #include "qqmlcompiler_p.h" #include "qqmlvmemetaobject_p.h" #include "qqmlexpression_p.h" #include "qqmlvaluetypeproxybinding_p.h" #include #include #include #include #include #include Q_DECLARE_METATYPE(QList) Q_DECLARE_METATYPE(QList) Q_DECLARE_METATYPE(QList) Q_DECLARE_METATYPE(QList) Q_DECLARE_METATYPE(QList) QT_BEGIN_NAMESPACE /*! \class QQmlProperty \since 5.0 \inmodule QtQml \brief The QQmlProperty class abstracts accessing properties on objects created from QML. As QML uses Qt's meta-type system all of the existing QMetaObject classes can be used to introspect and interact with objects created by QML. However, some of the new features provided by QML - such as type safety and attached properties - are most easily used through the QQmlProperty class that simplifies some of their natural complexity. Unlike QMetaProperty which represents a property on a class type, QQmlProperty encapsulates a property on a specific object instance. To read a property's value, programmers create a QQmlProperty instance and call the read() method. Likewise to write a property value the write() method is used. For example, for the following QML code: \qml // MyItem.qml import QtQuick 2.0 Text { text: "A bit of text" } \endqml The \l Text object's properties could be accessed using QQmlProperty, like this: \code #include #include ... QQuickView view(QUrl::fromLocalFile("MyItem.qml")); QQmlProperty property(view.rootObject(), "font.pixelSize"); qWarning() << "Current pixel size:" << property.read().toInt(); property.write(24); qWarning() << "Pixel size should now be 24:" << property.read().toInt(); \endcode The \l {Qt Quick 1} version of this class was named QDeclarativeProperty. */ /*! Create an invalid QQmlProperty. */ QQmlProperty::QQmlProperty() : d(0) { } /*! \internal */ QQmlProperty::~QQmlProperty() { if (d) d->release(); d = 0; } /*! Creates a QQmlProperty for the default property of \a obj. If there is no default property, an invalid QQmlProperty will be created. */ QQmlProperty::QQmlProperty(QObject *obj) : d(new QQmlPropertyPrivate) { d->initDefault(obj); } /*! Creates a QQmlProperty for the default property of \a obj using the \l{QQmlContext} {context} \a ctxt. If there is no default property, an invalid QQmlProperty will be created. */ QQmlProperty::QQmlProperty(QObject *obj, QQmlContext *ctxt) : d(new QQmlPropertyPrivate) { d->context = ctxt?QQmlContextData::get(ctxt):0; d->engine = ctxt?ctxt->engine():0; d->initDefault(obj); } /*! Creates a QQmlProperty for the default property of \a obj using the environment for instantiating QML components that is provided by \a engine. If there is no default property, an invalid QQmlProperty will be created. */ QQmlProperty::QQmlProperty(QObject *obj, QQmlEngine *engine) : d(new QQmlPropertyPrivate) { d->context = 0; d->engine = engine; d->initDefault(obj); } /*! Initialize from the default property of \a obj */ void QQmlPropertyPrivate::initDefault(QObject *obj) { if (!obj) return; QMetaProperty p = QQmlMetaType::defaultProperty(obj); core.load(p); if (core.isValid()) object = obj; } /*! Creates a QQmlProperty for the property \a name of \a obj. */ QQmlProperty::QQmlProperty(QObject *obj, const QString &name) : d(new QQmlPropertyPrivate) { d->initProperty(obj, name); if (!isValid()) d->object = 0; } /*! Creates a QQmlProperty for the property \a name of \a obj using the \l{QQmlContext} {context} \a ctxt. Creating a QQmlProperty without a context will render some properties - like attached properties - inaccessible. */ QQmlProperty::QQmlProperty(QObject *obj, const QString &name, QQmlContext *ctxt) : d(new QQmlPropertyPrivate) { d->context = ctxt?QQmlContextData::get(ctxt):0; d->engine = ctxt?ctxt->engine():0; d->initProperty(obj, name); if (!isValid()) { d->object = 0; d->context = 0; d->engine = 0; } } /*! Creates a QQmlProperty for the property \a name of \a obj using the environment for instantiating QML components that is provided by \a engine. */ QQmlProperty::QQmlProperty(QObject *obj, const QString &name, QQmlEngine *engine) : d(new QQmlPropertyPrivate) { d->context = 0; d->engine = engine; d->initProperty(obj, name); if (!isValid()) { d->object = 0; d->context = 0; d->engine = 0; } } QQmlPropertyPrivate::QQmlPropertyPrivate() : context(0), engine(0), object(0), isNameCached(false) { } QQmlContextData *QQmlPropertyPrivate::effectiveContext() const { if (context) return context; else if (engine) return QQmlContextData::get(engine->rootContext()); else return 0; } void QQmlPropertyPrivate::initProperty(QObject *obj, const QString &name) { if (!obj) return; QQmlTypeNameCache *typeNameCache = context?context->imports:0; QStringList path = name.split(QLatin1Char('.')); if (path.isEmpty()) return; QObject *currentObject = obj; // Everything up to the last property must be an "object type" property for (int ii = 0; ii < path.count() - 1; ++ii) { const QString &pathName = path.at(ii); if (typeNameCache) { QQmlTypeNameCache::Result r = typeNameCache->query(pathName); if (r.isValid()) { if (r.type) { QQmlAttachedPropertiesFunc func = r.type->attachedPropertiesFunction(); if (!func) return; // Not an attachable type currentObject = qmlAttachedPropertiesObjectById(r.type->attachedPropertiesId(), currentObject); if (!currentObject) return; // Something is broken with the attachable type } else if (r.importNamespace) { if ((ii + 1) == path.count()) return; // No type following the namespace ++ii; r = typeNameCache->query(path.at(ii), r.importNamespace); if (!r.type) return; // Invalid type in namespace QQmlAttachedPropertiesFunc func = r.type->attachedPropertiesFunction(); if (!func) return; // Not an attachable type currentObject = qmlAttachedPropertiesObjectById(r.type->attachedPropertiesId(), currentObject); if (!currentObject) return; // Something is broken with the attachable type } else if (r.scriptIndex != -1) { return; // Not a type } else { Q_ASSERT(!"Unreachable"); } continue; } } QQmlPropertyData local; QQmlPropertyData *property = QQmlPropertyCache::property(engine, currentObject, pathName, context, local); if (!property) return; // Not a property if (property->isFunction()) return; // Not an object property if (ii == (path.count() - 2) && QQmlValueTypeFactory::isValueType(property->propType)) { // We're now at a value type property const QMetaObject *valueTypeMetaObject = QQmlValueTypeFactory::metaObjectForMetaType(property->propType); if (!valueTypeMetaObject) return; // Not a value type int idx = valueTypeMetaObject->indexOfProperty(path.last().toUtf8().constData()); if (idx == -1) return; // Value type property does not exist QMetaProperty vtProp = valueTypeMetaObject->property(idx); Q_ASSERT(QQmlPropertyData::flagsForProperty(vtProp) <= QQmlPropertyData::ValueTypeFlagMask); Q_ASSERT(vtProp.userType() <= 0x0000FFFF); Q_ASSERT(idx <= 0x0000FFFF); object = currentObject; core = *property; core.setFlags(core.getFlags() | QQmlPropertyData::IsValueTypeVirtual); core.valueTypeFlags = QQmlPropertyData::flagsForProperty(vtProp); core.valueTypePropType = vtProp.userType(); core.valueTypeCoreIndex = idx; return; } else { if (!property->isQObject()) return; // Not an object property void *args[] = { ¤tObject, 0 }; QMetaObject::metacall(currentObject, QMetaObject::ReadProperty, property->coreIndex, args); if (!currentObject) return; // No value } } const QString &terminal = path.last(); if (terminal.count() >= 3 && terminal.at(0) == QLatin1Char('o') && terminal.at(1) == QLatin1Char('n') && terminal.at(2).isUpper()) { QString signalName = terminal.mid(2); signalName[0] = signalName.at(0).toLower(); // XXX - this code treats methods as signals QQmlData *ddata = QQmlData::get(currentObject, false); if (ddata && ddata->propertyCache) { // Try method QQmlPropertyData *d = ddata->propertyCache->property(signalName, currentObject, context); while (d && !d->isFunction()) d = ddata->propertyCache->overrideData(d); if (d) { object = currentObject; core = *d; return; } // Try property if (signalName.endsWith(QLatin1String("Changed"))) { QString propName = signalName.mid(0, signalName.length() - 7); QQmlPropertyData *d = ddata->propertyCache->property(propName, currentObject, context); while (d && d->isFunction()) d = ddata->propertyCache->overrideData(d); if (d && d->notifyIndex != -1) { object = currentObject; core = *ddata->propertyCache->signal(d->notifyIndex); return; } } } else { QMetaMethod method = findSignalByName(currentObject->metaObject(), signalName.toLatin1()); if (method.isValid()) { object = currentObject; core.load(method); return; } } } // Property QQmlPropertyData local; QQmlPropertyData *property = QQmlPropertyCache::property(engine, currentObject, terminal, context, local); if (property && !property->isFunction()) { object = currentObject; core = *property; nameCache = terminal; isNameCached = true; } } /*! \internal Returns the index of this property's signal, in the signal index range (see QObjectPrivate::signalIndex()). This is different from QMetaMethod::methodIndex(). */ int QQmlPropertyPrivate::signalIndex() const { Q_ASSERT(type() == QQmlProperty::SignalProperty); QMetaMethod m = object->metaObject()->method(core.coreIndex); return QMetaObjectPrivate::signalIndex(m); } /*! Create a copy of \a other. */ QQmlProperty::QQmlProperty(const QQmlProperty &other) { d = other.d; if (d) d->addref(); } /*! \enum QQmlProperty::PropertyTypeCategory This enum specifies a category of QML property. \value InvalidCategory The property is invalid, or is a signal property. \value List The property is a QQmlListProperty list property \value Object The property is a QObject derived type pointer \value Normal The property is a normal value property. */ /*! \enum QQmlProperty::Type This enum specifies a type of QML property. \value Invalid The property is invalid. \value Property The property is a regular Qt property. \value SignalProperty The property is a signal property. */ /*! Returns the property category. */ QQmlProperty::PropertyTypeCategory QQmlProperty::propertyTypeCategory() const { return d ? d->propertyTypeCategory() : InvalidCategory; } QQmlProperty::PropertyTypeCategory QQmlPropertyPrivate::propertyTypeCategory() const { uint type = this->type(); if (isValueType()) { return QQmlProperty::Normal; } else if (type & QQmlProperty::Property) { int type = propertyType(); if (type == QVariant::Invalid) return QQmlProperty::InvalidCategory; else if (QQmlValueTypeFactory::isValueType((uint)type)) return QQmlProperty::Normal; else if (core.isQObject()) return QQmlProperty::Object; else if (core.isQList()) return QQmlProperty::List; else return QQmlProperty::Normal; } return QQmlProperty::InvalidCategory; } /*! Returns the type name of the property, or 0 if the property has no type name. */ const char *QQmlProperty::propertyTypeName() const { if (!d) return 0; if (d->isValueType()) { const QMetaObject *valueTypeMetaObject = QQmlValueTypeFactory::metaObjectForMetaType(d->core.propType); Q_ASSERT(valueTypeMetaObject); return valueTypeMetaObject->property(d->core.valueTypeCoreIndex).typeName(); } else if (d->object && type() & Property && d->core.isValid()) { return d->object->metaObject()->property(d->core.coreIndex).typeName(); } else { return 0; } } /*! Returns true if \a other and this QQmlProperty represent the same property. */ bool QQmlProperty::operator==(const QQmlProperty &other) const { if (!d || !other.d) return false; // category is intentially omitted here as it is generated // from the other members return d->object == other.d->object && d->core.coreIndex == other.d->core.coreIndex && d->core.isValueTypeVirtual() == other.d->core.isValueTypeVirtual() && (!d->core.isValueTypeVirtual() || (d->core.valueTypeCoreIndex == other.d->core.valueTypeCoreIndex && d->core.valueTypePropType == other.d->core.valueTypePropType)); } /*! Returns the QVariant type of the property, or QVariant::Invalid if the property has no QVariant type. */ int QQmlProperty::propertyType() const { return d ? d->propertyType() : int(QVariant::Invalid); } bool QQmlPropertyPrivate::isValueType() const { return core.isValueTypeVirtual(); } int QQmlPropertyPrivate::propertyType() const { uint type = this->type(); if (isValueType()) { return core.valueTypePropType; } else if (type & QQmlProperty::Property) { return core.propType; } else { return QVariant::Invalid; } } QQmlProperty::Type QQmlPropertyPrivate::type() const { if (core.isFunction()) return QQmlProperty::SignalProperty; else if (core.isValid()) return QQmlProperty::Property; else return QQmlProperty::Invalid; } /*! Returns the type of the property. */ QQmlProperty::Type QQmlProperty::type() const { return d ? d->type() : Invalid; } /*! Returns true if this QQmlProperty represents a regular Qt property. */ bool QQmlProperty::isProperty() const { return type() & Property; } /*! Returns true if this QQmlProperty represents a QML signal property. */ bool QQmlProperty::isSignalProperty() const { return type() & SignalProperty; } /*! Returns the QQmlProperty's QObject. */ QObject *QQmlProperty::object() const { return d ? d->object : 0; } /*! Assign \a other to this QQmlProperty. */ QQmlProperty &QQmlProperty::operator=(const QQmlProperty &other) { if (d) d->release(); d = other.d; if (d) d->addref(); return *this; } /*! Returns true if the property is writable, otherwise false. */ bool QQmlProperty::isWritable() const { if (!d) return false; if (!d->object) return false; if (d->core.isQList()) //list return true; else if (d->core.isFunction()) //signal handler return false; else if (d->core.isValid()) //normal property return d->core.isWritable(); else return false; } /*! Returns true if the property is designable, otherwise false. */ bool QQmlProperty::isDesignable() const { if (!d) return false; if (type() & Property && d->core.isValid() && d->object) return d->object->metaObject()->property(d->core.coreIndex).isDesignable(); else return false; } /*! Returns true if the property is resettable, otherwise false. */ bool QQmlProperty::isResettable() const { if (!d) return false; if (type() & Property && d->core.isValid() && d->object) return d->core.isResettable(); else return false; } /*! Returns true if the QQmlProperty refers to a valid property, otherwise false. */ bool QQmlProperty::isValid() const { if (!d) return false; return type() != Invalid; } /*! Return the name of this QML property. */ QString QQmlProperty::name() const { if (!d) return QString(); if (!d->isNameCached) { // ### if (!d->object) { } else if (d->isValueType()) { QString rv = d->core.name(d->object) + QLatin1Char('.'); const QMetaObject *valueTypeMetaObject = QQmlValueTypeFactory::metaObjectForMetaType(d->core.propType); Q_ASSERT(valueTypeMetaObject); const char *vtName = valueTypeMetaObject->property(d->core.valueTypeCoreIndex).name(); rv += QString::fromUtf8(vtName); d->nameCache = rv; } else if (type() & SignalProperty) { QString name = QLatin1String("on") + d->core.name(d->object); name[2] = name.at(2).toUpper(); d->nameCache = name; } else { d->nameCache = d->core.name(d->object); } d->isNameCached = true; } return d->nameCache; } /*! Returns the \l{QMetaProperty} {Qt property} associated with this QML property. */ QMetaProperty QQmlProperty::property() const { if (!d) return QMetaProperty(); if (type() & Property && d->core.isValid() && d->object) return d->object->metaObject()->property(d->core.coreIndex); else return QMetaProperty(); } /*! Return the QMetaMethod for this property if it is a SignalProperty, otherwise returns an invalid QMetaMethod. */ QMetaMethod QQmlProperty::method() const { if (!d) return QMetaMethod(); if (type() & SignalProperty && d->object) return d->object->metaObject()->method(d->core.coreIndex); else return QMetaMethod(); } /*! Returns the binding associated with this property, or 0 if no binding exists. */ QQmlAbstractBinding * QQmlPropertyPrivate::binding(const QQmlProperty &that) { if (!that.d || !that.isProperty() || !that.d->object) return 0; return binding(that.d->object, that.d->core.coreIndex, that.d->core.getValueTypeCoreIndex()); } /*! Set the binding associated with this property to \a newBinding. Returns the existing binding (if any), otherwise 0. \a newBinding will be enabled, and the returned binding (if any) will be disabled. Ownership of \a newBinding transfers to QML. Ownership of the return value is assumed by the caller. \a flags is passed through to the binding and is used for the initial update (when the binding sets the initial value, it will use these flags for the write). */ QQmlAbstractBinding * QQmlPropertyPrivate::setBinding(const QQmlProperty &that, QQmlAbstractBinding *newBinding, WriteFlags flags) { if (!that.d || !that.isProperty() || !that.d->object) { if (newBinding) newBinding->destroy(); return 0; } if (newBinding) { // In the case that the new binding is provided, we must target the property it // is associated with. If we don't do this, retargetBinding() can fail. QObject *object = newBinding->object(); int pi = newBinding->propertyIndex(); int core; int vt = QQmlPropertyData::decodeValueTypePropertyIndex(pi, &core); return setBinding(object, core, vt, newBinding, flags); } else { return setBinding(that.d->object, that.d->core.coreIndex, that.d->core.getValueTypeCoreIndex(), newBinding, flags); } } QQmlAbstractBinding * QQmlPropertyPrivate::binding(QObject *object, int coreIndex, int valueTypeIndex) { QQmlData *data = QQmlData::get(object); if (!data) return 0; QQmlPropertyData *propertyData = data->propertyCache?data->propertyCache->property(coreIndex):0; if (propertyData && propertyData->isAlias()) { QQmlVMEMetaObject *vme = QQmlVMEMetaObject::getForProperty(object, coreIndex); QObject *aObject = 0; int aCoreIndex = -1; int aValueTypeIndex = -1; if (!vme->aliasTarget(coreIndex, &aObject, &aCoreIndex, &aValueTypeIndex) || aCoreIndex == -1) return 0; // This will either be a value type sub-reference or an alias to a value-type sub-reference not both Q_ASSERT(valueTypeIndex == -1 || aValueTypeIndex == -1); aValueTypeIndex = (valueTypeIndex == -1)?aValueTypeIndex:valueTypeIndex; return binding(aObject, aCoreIndex, aValueTypeIndex); } if (!data->hasBindingBit(coreIndex)) return 0; QQmlAbstractBinding *binding = data->bindings; while (binding && binding->propertyIndex() != coreIndex) binding = binding->nextBinding(); if (binding && valueTypeIndex != -1) { if (binding->bindingType() == QQmlAbstractBinding::ValueTypeProxy) { int index = QQmlPropertyData::encodeValueTypePropertyIndex(coreIndex, valueTypeIndex); binding = static_cast(binding)->binding(index); } } return binding; } void QQmlPropertyPrivate::findAliasTarget(QObject *object, int bindingIndex, QObject **targetObject, int *targetBindingIndex) { int coreIndex; int valueTypeIndex = QQmlPropertyData::decodeValueTypePropertyIndex(bindingIndex, &coreIndex); QQmlData *data = QQmlData::get(object, false); if (data) { QQmlPropertyData *propertyData = data->propertyCache?data->propertyCache->property(coreIndex):0; if (propertyData && propertyData->isAlias()) { QQmlVMEMetaObject *vme = QQmlVMEMetaObject::getForProperty(object, coreIndex); QObject *aObject = 0; int aCoreIndex = -1; int aValueTypeIndex = -1; if (vme->aliasTarget(coreIndex, &aObject, &aCoreIndex, &aValueTypeIndex)) { // This will either be a value type sub-reference or an alias to a value-type sub-reference not both Q_ASSERT(valueTypeIndex == -1 || aValueTypeIndex == -1); int aBindingIndex = aCoreIndex; if (aValueTypeIndex != -1) aBindingIndex = QQmlPropertyData::encodeValueTypePropertyIndex(aBindingIndex, aValueTypeIndex); else if (valueTypeIndex != -1) aBindingIndex = QQmlPropertyData::encodeValueTypePropertyIndex(aBindingIndex, valueTypeIndex); findAliasTarget(aObject, aBindingIndex, targetObject, targetBindingIndex); return; } } } *targetObject = object; *targetBindingIndex = bindingIndex; } QQmlAbstractBinding * QQmlPropertyPrivate::setBinding(QObject *object, int coreIndex, int valueTypeIndex, QQmlAbstractBinding *newBinding, WriteFlags flags) { QQmlData *data = QQmlData::get(object, 0 != newBinding); QQmlAbstractBinding *binding = 0; if (data) { QQmlPropertyData *propertyData = data->propertyCache?data->propertyCache->property(coreIndex):0; if (propertyData && propertyData->isAlias()) { QQmlVMEMetaObject *vme = QQmlVMEMetaObject::getForProperty(object, coreIndex); QObject *aObject = 0; int aCoreIndex = -1; int aValueTypeIndex = -1; if (!vme->aliasTarget(coreIndex, &aObject, &aCoreIndex, &aValueTypeIndex)) { if (newBinding) newBinding->destroy(); return 0; } // This will either be a value type sub-reference or an alias to a value-type sub-reference not both Q_ASSERT(valueTypeIndex == -1 || aValueTypeIndex == -1); aValueTypeIndex = (valueTypeIndex == -1)?aValueTypeIndex:valueTypeIndex; return setBinding(aObject, aCoreIndex, aValueTypeIndex, newBinding, flags); } } if (data && data->hasBindingBit(coreIndex)) { binding = data->bindings; while (binding && binding->propertyIndex() != coreIndex) binding = binding->nextBinding(); } int index = coreIndex; if (valueTypeIndex != -1) index = QQmlPropertyData::encodeValueTypePropertyIndex(index, valueTypeIndex); if (binding && valueTypeIndex != -1 && binding->bindingType() == QQmlAbstractBinding::ValueTypeProxy) binding = static_cast(binding)->binding(index); if (binding) { binding->removeFromObject(); binding->setEnabled(false, 0); } if (newBinding) { if (newBinding->propertyIndex() != index || newBinding->object() != object) newBinding->retargetBinding(object, index); Q_ASSERT(newBinding->propertyIndex() == index); Q_ASSERT(newBinding->object() == object); newBinding->addToObject(); newBinding->setEnabled(true, flags); } return binding; } QQmlAbstractBinding * QQmlPropertyPrivate::setBindingNoEnable(QObject *object, int coreIndex, int valueTypeIndex, QQmlAbstractBinding *newBinding) { QQmlData *data = QQmlData::get(object, 0 != newBinding); QQmlAbstractBinding *binding = 0; if (data) { QQmlPropertyData *propertyData = data->propertyCache?data->propertyCache->property(coreIndex):0; if (propertyData && propertyData->isAlias()) { QQmlVMEMetaObject *vme = QQmlVMEMetaObject::getForProperty(object, coreIndex); QObject *aObject = 0; int aCoreIndex = -1; int aValueTypeIndex = -1; if (!vme->aliasTarget(coreIndex, &aObject, &aCoreIndex, &aValueTypeIndex)) { if (newBinding) newBinding->destroy(); return 0; } // This will either be a value type sub-reference or an alias to a value-type sub-reference not both Q_ASSERT(valueTypeIndex == -1 || aValueTypeIndex == -1); aValueTypeIndex = (valueTypeIndex == -1)?aValueTypeIndex:valueTypeIndex; return setBindingNoEnable(aObject, aCoreIndex, aValueTypeIndex, newBinding); } } if (data && data->hasBindingBit(coreIndex)) { binding = data->bindings; while (binding && binding->propertyIndex() != coreIndex) binding = binding->nextBinding(); } int index = coreIndex; if (valueTypeIndex != -1) index = QQmlPropertyData::encodeValueTypePropertyIndex(index, valueTypeIndex); if (binding && valueTypeIndex != -1 && binding->bindingType() == QQmlAbstractBinding::ValueTypeProxy) binding = static_cast(binding)->binding(index); if (binding) binding->removeFromObject(); if (newBinding) { if (newBinding->propertyIndex() != index || newBinding->object() != object) newBinding->retargetBinding(object, index); Q_ASSERT(newBinding->propertyIndex() == index); Q_ASSERT(newBinding->object() == object); newBinding->addToObject(); } return binding; } /*! Returns the expression associated with this signal property, or 0 if no signal expression exists. */ QQmlBoundSignalExpression * QQmlPropertyPrivate::signalExpression(const QQmlProperty &that) { if (!(that.type() & QQmlProperty::SignalProperty)) return 0; QQmlData *data = QQmlData::get(that.d->object); if (!data) return 0; QQmlAbstractBoundSignal *signalHandler = data->signalHandlers; while (signalHandler && signalHandler->index() != QQmlPropertyPrivate::get(that)->signalIndex()) signalHandler = signalHandler->m_nextSignal; if (signalHandler) return signalHandler->expression(); return 0; } /*! Set the signal expression associated with this signal property to \a expr. Returns the existing signal expression (if any), otherwise null. A reference to \a expr will be added by QML. Ownership of the return value reference is assumed by the caller. */ QQmlBoundSignalExpressionPointer QQmlPropertyPrivate::setSignalExpression(const QQmlProperty &that, QQmlBoundSignalExpression *expr) { if (expr) expr->addref(); return QQmlPropertyPrivate::takeSignalExpression(that, expr); } /*! Set the signal expression associated with this signal property to \a expr. Returns the existing signal expression (if any), otherwise null. Ownership of \a expr transfers to QML. Ownership of the return value reference is assumed by the caller. */ QQmlBoundSignalExpressionPointer QQmlPropertyPrivate::takeSignalExpression(const QQmlProperty &that, QQmlBoundSignalExpression *expr) { if (!(that.type() & QQmlProperty::SignalProperty)) { if (expr) expr->release(); return 0; } QQmlData *data = QQmlData::get(that.d->object, 0 != expr); if (!data) return 0; QQmlAbstractBoundSignal *signalHandler = data->signalHandlers; while (signalHandler && signalHandler->index() != QQmlPropertyPrivate::get(that)->signalIndex()) signalHandler = signalHandler->m_nextSignal; if (signalHandler) return signalHandler->takeExpression(expr); if (expr) { int signalIndex = QQmlPropertyPrivate::get(that)->signalIndex(); QQmlBoundSignal *signal = new QQmlBoundSignal(that.d->object, signalIndex, that.d->object, expr->context()->engine); signal->takeExpression(expr); } return 0; } /*! Returns the property value. */ QVariant QQmlProperty::read() const { if (!d) return QVariant(); if (!d->object) return QVariant(); if (type() & SignalProperty) { return QVariant(); } else if (type() & Property) { return d->readValueProperty(); } return QVariant(); } /*! Return the \a name property value of \a object. This method is equivalent to: \code QQmlProperty p(object, name); p.read(); \endcode */ QVariant QQmlProperty::read(const QObject *object, const QString &name) { QQmlProperty p(const_cast(object), name); return p.read(); } /*! Return the \a name property value of \a object using the \l{QQmlContext} {context} \a ctxt. This method is equivalent to: \code QQmlProperty p(object, name, context); p.read(); \endcode */ QVariant QQmlProperty::read(const QObject *object, const QString &name, QQmlContext *ctxt) { QQmlProperty p(const_cast(object), name, ctxt); return p.read(); } /*! Return the \a name property value of \a object using the environment for instantiating QML components that is provided by \a engine. . This method is equivalent to: \code QQmlProperty p(object, name, engine); p.read(); \endcode */ QVariant QQmlProperty::read(const QObject *object, const QString &name, QQmlEngine *engine) { QQmlProperty p(const_cast(object), name, engine); return p.read(); } QVariant QQmlPropertyPrivate::readValueProperty() { if (isValueType()) { QQmlValueType *valueType = QQmlValueTypeFactory::valueType(core.propType); Q_ASSERT(valueType); valueType->read(object, core.coreIndex); return valueType->metaObject()->property(core.valueTypeCoreIndex).read(valueType); } else if (core.isQList()) { QQmlListProperty prop; void *args[] = { &prop, 0 }; QMetaObject::metacall(object, QMetaObject::ReadProperty, core.coreIndex, args); return QVariant::fromValue(QQmlListReferencePrivate::init(prop, core.propType, engine)); } else if (core.isQObject()) { QObject *rv = 0; void *args[] = { &rv, 0 }; QMetaObject::metacall(object, QMetaObject::ReadProperty, core.coreIndex, args); return QVariant::fromValue(rv); } else { if (!core.propType) // Unregistered type return object->metaObject()->property(core.coreIndex).read(object); QVariant value; int status = -1; void *args[] = { 0, &value, &status }; if (core.propType == QMetaType::QVariant) { args[0] = &value; } else { value = QVariant(core.propType, (void*)0); args[0] = value.data(); } QMetaObject::metacall(object, QMetaObject::ReadProperty, core.coreIndex, args); if (core.propType != QMetaType::QVariant && args[0] != value.data()) return QVariant((QVariant::Type)core.propType, args[0]); return value; } } // helper function to allow assignment / binding to QList properties. static QVariant resolvedUrlSequence(const QVariant &value, QQmlContextData *context) { QList urls; if (value.userType() == qMetaTypeId()) { urls.append(value.toUrl()); } else if (value.userType() == qMetaTypeId()) { urls.append(QUrl(value.toString())); } else if (value.userType() == qMetaTypeId()) { urls.append(QUrl(QString::fromUtf8(value.toByteArray()))); } else if (value.userType() == qMetaTypeId >()) { urls = value.value >(); } else if (value.userType() == qMetaTypeId()) { QStringList urlStrings = value.value(); for (int i = 0; i < urlStrings.size(); ++i) urls.append(QUrl(urlStrings.at(i))); } else if (value.userType() == qMetaTypeId >()) { QList urlStrings = value.value >(); for (int i = 0; i < urlStrings.size(); ++i) urls.append(QUrl(urlStrings.at(i))); } // note: QList is not currently supported. QList resolvedUrls; for (int i = 0; i < urls.size(); ++i) { QUrl u = urls.at(i); if (context && u.isRelative() && !u.isEmpty()) u = context->resolvedUrl(u); resolvedUrls.append(u); } return QVariant::fromValue >(resolvedUrls); } //writeEnumProperty MIRRORS the relelvant bit of QMetaProperty::write AND MUST BE KEPT IN SYNC! bool QQmlPropertyPrivate::writeEnumProperty(const QMetaProperty &prop, int idx, QObject *object, const QVariant &value, int flags) { if (!object || !prop.isWritable()) return false; QVariant v = value; if (prop.isEnumType()) { QMetaEnum menum = prop.enumerator(); if (v.userType() == QVariant::String #ifdef QT3_SUPPORT || v.userType() == QVariant::CString #endif ) { bool ok; if (prop.isFlagType()) v = QVariant(menum.keysToValue(value.toByteArray(), &ok)); else v = QVariant(menum.keyToValue(value.toByteArray(), &ok)); if (!ok) return false; } else if (v.userType() != QVariant::Int && v.userType() != QVariant::UInt) { int enumMetaTypeId = QMetaType::type(QByteArray(menum.scope() + QByteArray("::") + menum.name())); if ((enumMetaTypeId == QMetaType::UnknownType) || (v.userType() != enumMetaTypeId) || !v.constData()) return false; v = QVariant(*reinterpret_cast(v.constData())); } v.convert(QVariant::Int); } // 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; void *argv[] = { v.data(), &v, &status, &flags }; QMetaObject::metacall(object, QMetaObject::WriteProperty, idx, argv); return status; } bool QQmlPropertyPrivate::writeValueProperty(const QVariant &value, WriteFlags flags) { return writeValueProperty(object, core, value, effectiveContext(), flags); } bool QQmlPropertyPrivate::writeValueProperty(QObject *object, const QQmlPropertyData &core, const QVariant &value, QQmlContextData *context, WriteFlags flags) { // Remove any existing bindings on this property if (!(flags & DontRemoveBinding) && object) { QQmlAbstractBinding *binding = setBinding(object, core.coreIndex, core.getValueTypeCoreIndex(), 0, flags); if (binding) binding->destroy(); } bool rv = false; if (core.isValueTypeVirtual()) { QQmlValueType *writeBack = QQmlValueTypeFactory::valueType(core.propType); writeBack->read(object, core.coreIndex); QQmlPropertyData data = core; data.setFlags(QQmlPropertyData::Flag(core.valueTypeFlags)); data.coreIndex = core.valueTypeCoreIndex; data.propType = core.valueTypePropType; rv = write(writeBack, data, value, context, flags); writeBack->write(object, core.coreIndex, flags); } else { rv = write(object, core, value, context, flags); } return rv; } bool QQmlPropertyPrivate::write(QObject *object, const QQmlPropertyData &property, const QVariant &value, QQmlContextData *context, WriteFlags flags) { int coreIdx = property.coreIndex; int status = -1; //for dbus if (property.isEnum()) { QMetaProperty prop = object->metaObject()->property(property.coreIndex); QVariant v = value; // Enum values come through the script engine as doubles if (value.userType() == QVariant::Double) { double integral; double fractional = modf(value.toDouble(), &integral); if (qFuzzyIsNull(fractional)) v.convert(QVariant::Int); } return writeEnumProperty(prop, coreIdx, object, v, flags); } int propertyType = property.propType; int variantType = value.userType(); QQmlEnginePrivate *enginePriv = QQmlEnginePrivate::get(context); if (propertyType == QVariant::Url) { QUrl u; bool found = false; if (variantType == QVariant::Url) { u = value.toUrl(); found = true; } else if (variantType == QVariant::ByteArray) { QString input(QString::fromUtf8(value.toByteArray())); // Encoded dir-separators defeat QUrl processing - decode them first input.replace(QLatin1String("%2f"), QLatin1String("/"), Qt::CaseInsensitive); u = QUrl(input); found = true; } else if (variantType == QVariant::String) { QString input(value.toString()); // Encoded dir-separators defeat QUrl processing - decode them first input.replace(QLatin1String("%2f"), QLatin1String("/"), Qt::CaseInsensitive); u = QUrl(input); found = true; } if (!found) return false; if (context && u.isRelative() && !u.isEmpty()) u = context->resolvedUrl(u); int status = -1; void *argv[] = { &u, 0, &status, &flags }; QMetaObject::metacall(object, QMetaObject::WriteProperty, coreIdx, argv); } else if (propertyType == qMetaTypeId >()) { QList urlSeq = resolvedUrlSequence(value, context).value >(); int status = -1; void *argv[] = { &urlSeq, 0, &status, &flags }; QMetaObject::metacall(object, QMetaObject::WriteProperty, coreIdx, argv); } else if (variantType == propertyType) { void *a[] = { const_cast(value.constData()), 0, &status, &flags }; QMetaObject::metacall(object, QMetaObject::WriteProperty, coreIdx, a); } else if (qMetaTypeId() == propertyType) { void *a[] = { const_cast(&value), 0, &status, &flags }; QMetaObject::metacall(object, QMetaObject::WriteProperty, coreIdx, a); } else if (property.isQObject()) { QQmlMetaObject valMo = rawMetaObjectForType(enginePriv, value.userType()); if (valMo.isNull()) return false; QObject *o = *(QObject *const *)value.constData(); QQmlMetaObject propMo = rawMetaObjectForType(enginePriv, propertyType); if (o) valMo = o; if (QQmlMetaObject::canConvert(valMo, propMo)) { void *args[] = { &o, 0, &status, &flags }; QMetaObject::metacall(object, QMetaObject::WriteProperty, coreIdx, args); } else if (!o && QQmlMetaObject::canConvert(propMo, valMo)) { // In the case of a null QObject, we assign the null if there is // any change that the null variant type could be up or down cast to // the property type. void *args[] = { &o, 0, &status, &flags }; QMetaObject::metacall(object, QMetaObject::WriteProperty, coreIdx, args); } else { return false; } } else if (property.isQList()) { QQmlMetaObject listType; if (enginePriv) { listType = enginePriv->rawMetaObjectForType(enginePriv->listType(property.propType)); } else { QQmlType *type = QQmlMetaType::qmlType(QQmlMetaType::listType(property.propType)); if (!type) return false; listType = type->baseMetaObject(); } if (listType.isNull()) return false; QQmlListProperty prop; void *args[] = { &prop, 0 }; QMetaObject::metacall(object, QMetaObject::ReadProperty, coreIdx, args); if (!prop.clear) return false; prop.clear(&prop); if (value.userType() == qMetaTypeId()) { QQmlListReference qdlr = value.value(); for (int ii = 0; ii < qdlr.count(); ++ii) { QObject *o = qdlr.at(ii); if (o && !QQmlMetaObject::canConvert(o, listType)) o = 0; prop.append(&prop, (void *)o); } } else if (value.userType() == qMetaTypeId >()) { const QList &list = qvariant_cast >(value); for (int ii = 0; ii < list.count(); ++ii) { QObject *o = list.at(ii); if (o && !QQmlMetaObject::canConvert(o, listType)) o = 0; prop.append(&prop, (void *)o); } } else { QObject *o = enginePriv?enginePriv->toQObject(value):QQmlMetaType::toQObject(value); if (o && !QQmlMetaObject::canConvert(o, listType)) o = 0; prop.append(&prop, (void *)o); } } else { Q_ASSERT(variantType != propertyType); bool ok = false; QVariant v; if (variantType == QVariant::String) { const QString &str = value.toString(); const bool targetIsChar = (propertyType == qMetaTypeId() || propertyType == qMetaTypeId() || propertyType == qMetaTypeId()); // If the string contains only one character and the target is a char, try converting it. if (targetIsChar) { if (str.size() != 1) return false; // We can only convert if the string contains exactly one character. const QChar &qChar = str.at(0); if (propertyType == qMetaTypeId()) { v = qChar; ok = true; } else if (propertyType == qMetaTypeId() || propertyType == qMetaTypeId()) { const char c = qChar.toLatin1(); v = c; ok = (qChar == c); } } else { v = QQmlStringConverters::variantFromString(str, propertyType, &ok); } } if (!ok) { v = value; if (v.convert(propertyType)) { ok = true; } else if (v.isValid() && value.isNull()) { // For historical reasons converting a null QVariant to another type will do the trick // but return false anyway. This is caught with the above condition and considered a // successful conversion. Q_ASSERT(v.userType() == propertyType); ok = true; } else if ((uint)propertyType >= QVariant::UserType && variantType == QVariant::String) { QQmlMetaType::StringConverter con = QQmlMetaType::customStringConverter(propertyType); if (con) { v = con(value.toString()); if (v.userType() == propertyType) ok = true; } } } if (!ok) { // the only other option is that they are assigning a single value // to a sequence type property (eg, an int to a QList property). // Note that we've already handled single-value assignment to QList properties. if (variantType == QVariant::Int && propertyType == qMetaTypeId >()) { QList list; list << value.toInt(); v = QVariant::fromValue >(list); ok = true; } else if ((variantType == QVariant::Double || variantType == QVariant::Int) && (propertyType == qMetaTypeId >())) { QList list; list << value.toReal(); v = QVariant::fromValue >(list); ok = true; } else if (variantType == QVariant::Bool && propertyType == qMetaTypeId >()) { QList list; list << value.toBool(); v = QVariant::fromValue >(list); ok = true; } else if (variantType == QVariant::String && propertyType == qMetaTypeId >()) { QList list; list << value.toString(); v = QVariant::fromValue >(list); ok = true; } else if (variantType == QVariant::String && propertyType == qMetaTypeId()) { QStringList list; list << value.toString(); v = QVariant::fromValue(list); ok = true; } } if (ok) { void *a[] = { const_cast(v.constData()), 0, &status, &flags}; QMetaObject::metacall(object, QMetaObject::WriteProperty, coreIdx, a); } else { return false; } } return true; } // Returns true if successful, false if an error description was set on expression bool QQmlPropertyPrivate::writeBinding(QObject *object, const QQmlPropertyData &core, QQmlContextData *context, QQmlJavaScriptExpression *expression, const QV4::Value &result, bool isUndefined, WriteFlags flags) { Q_ASSERT(object); Q_ASSERT(core.coreIndex != -1); QQmlEngine *engine = context->engine; QV8Engine *v8engine = QQmlEnginePrivate::getV8Engine(engine); #define QUICK_STORE(cpptype, conversion) \ { \ cpptype o = (conversion); \ int status = -1; \ void *argv[] = { &o, 0, &status, &flags }; \ QMetaObject::metacall(object, QMetaObject::WriteProperty, core.coreIndex, argv); \ return true; \ } \ if (!isUndefined && !core.isValueTypeVirtual()) { switch (core.propType) { case QMetaType::Int: if (result.isInteger()) QUICK_STORE(int, result.integerValue()) else if (result.isNumber()) QUICK_STORE(int, result.doubleValue()) break; case QMetaType::Double: if (result.isNumber()) QUICK_STORE(double, result.asDouble()) break; case QMetaType::Float: if (result.isNumber()) QUICK_STORE(float, result.asDouble()) break; case QMetaType::QString: if (result.isString()) QUICK_STORE(QString, result.toQStringNoThrow()) break; default: if (const QV4::QQmlValueTypeWrapper *vtw = result.as()) { if (vtw->d()->valueType->typeId == core.propType) { return vtw->write(object, core.coreIndex); } } break; } } #undef QUICK_STORE int type = core.isValueTypeVirtual()?core.valueTypePropType:core.propType; QQmlJavaScriptExpression::DeleteWatcher watcher(expression); QVariant value; bool isVarProperty = core.isVarProperty(); if (isUndefined) { } else if (core.isQList()) { value = QV8Engine::getV4(v8engine)->toVariant(result, qMetaTypeId >()); } else if (result.isNull() && core.isQObject()) { value = QVariant::fromValue((QObject *)0); } else if (core.propType == qMetaTypeId >()) { value = resolvedUrlSequence(QV8Engine::getV4(v8engine)->toVariant(result, qMetaTypeId >()), context); } else if (!isVarProperty && type != qMetaTypeId()) { value = QV8Engine::getV4(v8engine)->toVariant(result, type); } if (expression->hasError()) { return false; } else if (isVarProperty) { QV4::FunctionObject *f = result.asFunctionObject(); if (f && f->isBinding()) { // we explicitly disallow this case to avoid confusion. Users can still store one // in an array in a var property if they need to, but the common case is user error. expression->delayedError()->setErrorDescription(QLatin1String("Invalid use of Qt.binding() in a binding declaration.")); expression->delayedError()->setErrorObject(object); return false; } QQmlVMEMetaObject *vmemo = QQmlVMEMetaObject::get(object); Q_ASSERT(vmemo); vmemo->setVMEProperty(core.coreIndex, result); } else if (isUndefined && core.isResettable()) { void *args[] = { 0 }; QMetaObject::metacall(object, QMetaObject::ResetProperty, core.coreIndex, args); } else if (isUndefined && type == qMetaTypeId()) { writeValueProperty(object, core, QVariant(), context, flags); } else if (type == qMetaTypeId()) { QV4::FunctionObject *f = result.asFunctionObject(); if (f && f->isBinding()) { expression->delayedError()->setErrorDescription(QLatin1String("Invalid use of Qt.binding() in a binding declaration.")); expression->delayedError()->setErrorObject(object); return false; } writeValueProperty(object, core, QVariant::fromValue( QJSValue(QV8Engine::getV4(v8engine), result.asReturnedValue())), context, flags); } else if (isUndefined) { QString errorStr = QLatin1String("Unable to assign [undefined] to "); if (!QMetaType::typeName(type)) errorStr += QLatin1String("[unknown property type]"); else errorStr += QLatin1String(QMetaType::typeName(type)); expression->delayedError()->setErrorDescription(errorStr); expression->delayedError()->setErrorObject(object); return false; } else if (QV4::FunctionObject *f = result.asFunctionObject()) { if (f->isBinding()) expression->delayedError()->setErrorDescription(QLatin1String("Invalid use of Qt.binding() in a binding declaration.")); else expression->delayedError()->setErrorDescription(QLatin1String("Unable to assign a function to a property of any type other than var.")); expression->delayedError()->setErrorObject(object); return false; } else if (!writeValueProperty(object, core, value, context, flags)) { if (watcher.wasDeleted()) return true; const char *valueType = 0; const char *propertyType = 0; if (value.userType() == QMetaType::QObjectStar) { if (QObject *o = *(QObject *const *)value.constData()) { valueType = o->metaObject()->className(); QQmlMetaObject propertyMetaObject = rawMetaObjectForType(QQmlEnginePrivate::get(engine), type); if (!propertyMetaObject.isNull()) propertyType = propertyMetaObject.className(); } } else if (value.userType() != QVariant::Invalid) { if (value.userType() == QMetaType::VoidStar) valueType = "null"; else valueType = QMetaType::typeName(value.userType()); } if (!valueType) valueType = "undefined"; if (!propertyType) propertyType = QMetaType::typeName(type); if (!propertyType) propertyType = "[unknown property type]"; expression->delayedError()->setErrorDescription(QLatin1String("Unable to assign ") + QLatin1String(valueType) + QLatin1String(" to ") + QLatin1String(propertyType)); expression->delayedError()->setErrorObject(object); return false; } return true; } QQmlMetaObject QQmlPropertyPrivate::rawMetaObjectForType(QQmlEnginePrivate *engine, int userType) { QMetaType metaType(userType); if ((metaType.flags() & QMetaType::PointerToQObject) && metaType.metaObject()) return metaType.metaObject(); if (engine) return engine->rawMetaObjectForType(userType); QQmlType *type = QQmlMetaType::qmlType(userType); if (type) return QQmlMetaObject(type->baseMetaObject()); return QQmlMetaObject((QObject*)0); } /*! Sets the property value to \a value and returns true. Returns false if the property can't be set because the \a value is the wrong type, for example. */ bool QQmlProperty::write(const QVariant &value) const { return QQmlPropertyPrivate::write(*this, value, 0); } /*! Writes \a value to the \a name property of \a object. This method is equivalent to: \code QQmlProperty p(object, name); p.write(value); \endcode */ bool QQmlProperty::write(QObject *object, const QString &name, const QVariant &value) { QQmlProperty p(object, name); return p.write(value); } /*! Writes \a value to the \a name property of \a object using the \l{QQmlContext} {context} \a ctxt. This method is equivalent to: \code QQmlProperty p(object, name, ctxt); p.write(value); \endcode */ bool QQmlProperty::write(QObject *object, const QString &name, const QVariant &value, QQmlContext *ctxt) { QQmlProperty p(object, name, ctxt); return p.write(value); } /*! Writes \a value to the \a name property of \a object using the environment for instantiating QML components that is provided by \a engine. This method is equivalent to: \code QQmlProperty p(object, name, engine); p.write(value); \endcode */ bool QQmlProperty::write(QObject *object, const QString &name, const QVariant &value, QQmlEngine *engine) { QQmlProperty p(object, name, engine); return p.write(value); } /*! Resets the property and returns true if the property is resettable. If the property is not resettable, nothing happens and false is returned. */ bool QQmlProperty::reset() const { if (isResettable()) { void *args[] = { 0 }; QMetaObject::metacall(d->object, QMetaObject::ResetProperty, d->core.coreIndex, args); return true; } else { return false; } } bool QQmlPropertyPrivate::write(const QQmlProperty &that, const QVariant &value, WriteFlags flags) { if (!that.d) return false; if (that.d->object && that.type() & QQmlProperty::Property && that.d->core.isValid() && that.isWritable()) return that.d->writeValueProperty(value, flags); else return false; } /*! Returns true if the property has a change notifier signal, otherwise false. */ bool QQmlProperty::hasNotifySignal() const { if (type() & Property && d->object) { return d->object->metaObject()->property(d->core.coreIndex).hasNotifySignal(); } return false; } /*! Returns true if the property needs a change notifier signal for bindings to remain upto date, false otherwise. Some properties, such as attached properties or those whose value never changes, do not require a change notifier. */ bool QQmlProperty::needsNotifySignal() const { return type() & Property && !property().isConstant(); } /*! Connects the property's change notifier signal to the specified \a method of the \a dest object and returns true. Returns false if this metaproperty does not represent a regular Qt property or if it has no change notifier signal, or if the \a dest object does not have the specified \a method. */ bool QQmlProperty::connectNotifySignal(QObject *dest, int method) const { if (!(type() & Property) || !d->object) return false; QMetaProperty prop = d->object->metaObject()->property(d->core.coreIndex); if (prop.hasNotifySignal()) { return QQmlPropertyPrivate::connect(d->object, prop.notifySignalIndex(), dest, method, Qt::DirectConnection); } else { return false; } } /*! Connects the property's change notifier signal to the specified \a slot of the \a dest object and returns true. Returns false if this metaproperty does not represent a regular Qt property or if it has no change notifier signal, or if the \a dest object does not have the specified \a slot. */ bool QQmlProperty::connectNotifySignal(QObject *dest, const char *slot) const { if (!(type() & Property) || !d->object) return false; QMetaProperty prop = d->object->metaObject()->property(d->core.coreIndex); if (prop.hasNotifySignal()) { QByteArray signal('2' + prop.notifySignal().methodSignature()); return QObject::connect(d->object, signal.constData(), dest, slot); } else { return false; } } /*! Return the Qt metaobject index of the property. */ int QQmlProperty::index() const { return d ? d->core.coreIndex : -1; } int QQmlPropertyPrivate::valueTypeCoreIndex(const QQmlProperty &that) { return that.d ? that.d->core.getValueTypeCoreIndex() : -1; } /*! Returns the "property index" for use in bindings. The top 16 bits are the value type offset, and 0 otherwise. The bottom 16 bits are the regular property index. */ int QQmlPropertyPrivate::bindingIndex(const QQmlProperty &that) { if (!that.d) return -1; return bindingIndex(that.d->core); } int QQmlPropertyPrivate::bindingIndex(const QQmlPropertyData &that) { int rv = that.coreIndex; if (rv != -1 && that.isValueTypeVirtual()) rv = rv | (that.valueTypeCoreIndex << 16); return rv; } QQmlPropertyData QQmlPropertyPrivate::saveValueType(const QQmlPropertyData &base, const QMetaObject *subObject, int subIndex, QQmlEngine *) { QMetaProperty subProp = subObject->property(subIndex); QQmlPropertyData core = base; core.setFlags(core.getFlags() | QQmlPropertyData::IsValueTypeVirtual); core.valueTypeFlags = QQmlPropertyData::flagsForProperty(subProp); core.valueTypeCoreIndex = subIndex; core.valueTypePropType = subProp.userType(); return core; } QQmlProperty QQmlPropertyPrivate::restore(QObject *object, const QQmlPropertyData &data, QQmlContextData *ctxt) { QQmlProperty prop; prop.d = new QQmlPropertyPrivate; prop.d->object = object; prop.d->context = ctxt; prop.d->engine = ctxt?ctxt->engine:0; prop.d->core = data; return prop; } /*! Return the signal corresponding to \a name */ QMetaMethod QQmlPropertyPrivate::findSignalByName(const QMetaObject *mo, const QByteArray &name) { Q_ASSERT(mo); int methods = mo->methodCount(); for (int ii = methods - 1; ii >= 2; --ii) { // >= 2 to block the destroyed signal QMetaMethod method = mo->method(ii); if (method.name() == name && (method.methodType() & QMetaMethod::Signal)) return method; } // If no signal is found, but the signal is of the form "onBlahChanged", // return the notify signal for the property "Blah" if (name.endsWith("Changed")) { QByteArray propName = name.mid(0, name.length() - 7); int propIdx = mo->indexOfProperty(propName.constData()); if (propIdx >= 0) { QMetaProperty prop = mo->property(propIdx); if (prop.hasNotifySignal()) return prop.notifySignal(); } } return QMetaMethod(); } /*! \internal If \a indexInSignalRange is true, \a index is treated as a signal index (see QObjectPrivate::signalIndex()), otherwise it is treated as a method index (QMetaMethod::methodIndex()). */ static inline void flush_vme_signal(const QObject *object, int index, bool indexInSignalRange) { QQmlData *data = static_cast(QObjectPrivate::get(const_cast(object))->declarativeData); if (data && data->propertyCache) { QQmlPropertyData *property = indexInSignalRange ? data->propertyCache->signal(index) : data->propertyCache->method(index); if (property && property->isVMESignal()) { QQmlVMEMetaObject *vme; if (indexInSignalRange) vme = QQmlVMEMetaObject::getForSignal(const_cast(object), index); else vme = QQmlVMEMetaObject::getForMethod(const_cast(object), index); vme->connectAliasSignal(index, indexInSignalRange); } } } /*! Connect \a sender \a signal_index to \a receiver \a method_index with the specified \a type and \a types. This behaves identically to QMetaObject::connect() except that it connects any lazy "proxy" signal connections set up by QML. It is possible that this logic should be moved to QMetaObject::connect(). */ bool QQmlPropertyPrivate::connect(const QObject *sender, int signal_index, const QObject *receiver, int method_index, int type, int *types) { static const bool indexInSignalRange = false; flush_vme_signal(sender, signal_index, indexInSignalRange); flush_vme_signal(receiver, method_index, indexInSignalRange); return QMetaObject::connect(sender, signal_index, receiver, method_index, type, types); } /*! \internal \a signal_index MUST be in the signal index range (see QObjectPrivate::signalIndex()). This is different from QMetaMethod::methodIndex(). */ void QQmlPropertyPrivate::flushSignal(const QObject *sender, int signal_index) { static const bool indexInSignalRange = true; flush_vme_signal(sender, signal_index, indexInSignalRange); } QT_END_NAMESPACE