/**************************************************************************** ** ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). ** All rights reserved. ** Contact: Nokia Corporation (qt-info@nokia.com) ** ** This file is part of the QtCore module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** No Commercial Usage ** This file contains pre-release code and may not be distributed. ** You may use this file in accordance with the terms and conditions ** contained in the Technology Preview License Agreement accompanying ** this package. ** ** 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 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 2.1 requirements ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** In addition, as a special exception, Nokia gives you certain additional ** rights. These rights are described in the Nokia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** If you have questions regarding the use of this file, please contact ** Nokia at qt-info@nokia.com. ** ** ** ** ** ** ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qmetaobject.h" #include "qmetatype.h" #include "qobject.h" #include #include #include #include #include #include #include #include #include #include #include "private/qobject_p.h" #include "private/qmetaobject_p.h" #include QT_BEGIN_NAMESPACE /*! \class QMetaObject \brief The QMetaObject class contains meta-information about Qt objects. \ingroup objectmodel The Qt \l{Meta-Object System} in Qt is responsible for the signals and slots inter-object communication mechanism, runtime type information, and the Qt property system. A single QMetaObject instance is created for each QObject subclass that is used in an application, and this instance stores all the meta-information for the QObject subclass. This object is available as QObject::metaObject(). This class is not normally required for application programming, but it is useful if you write meta-applications, such as scripting engines or GUI builders. The functions you are most likely to find useful are these: \list \o className() returns the name of a class. \o superClass() returns the superclass's meta-object. \o method() and methodCount() provide information about a class's meta-methods (signals, slots and other \l{Q_INVOKABLE}{invokable} member functions). \o enumerator() and enumeratorCount() and provide information about a class's enumerators. \o propertyCount() and property() provide information about a class's properties. \o constructor() and constructorCount() provide information about a class's meta-constructors. \endlist The index functions indexOfConstructor(), indexOfMethod(), indexOfEnumerator(), and indexOfProperty() map names of constructors, member functions, enumerators, or properties to indexes in the meta-object. For example, Qt uses indexOfMethod() internally when you connect a signal to a slot. Classes can also have a list of \e{name}--\e{value} pairs of additional class information, stored in QMetaClassInfo objects. The number of pairs is returned by classInfoCount(), single pairs are returned by classInfo(), and you can search for pairs with indexOfClassInfo(). \sa QMetaClassInfo, QMetaEnum, QMetaMethod, QMetaProperty, QMetaType, {Meta-Object System} */ /*! \enum QMetaObject::Call \internal \value InvokeSlot \value EmitSignal \value ReadProperty \value WriteProperty \value ResetProperty \value QueryPropertyDesignable \value QueryPropertyScriptable \value QueryPropertyStored \value QueryPropertyEditable \value QueryPropertyUser \value CreateInstance */ /*! \enum QMetaMethod::Access This enum describes the access level of a method, following the conventions used in C++. \value Private \value Protected \value Public */ static inline const QMetaObjectPrivate *priv(const uint* data) { return reinterpret_cast(data); } /*! \since 4.5 Constructs a new instance of this class. You can pass up to ten arguments (\a val0, \a val1, \a val2, \a val3, \a val4, \a val5, \a val6, \a val7, \a val8, and \a val9) to the constructor. Returns the new object, or 0 if no suitable constructor is available. Note that only constructors that are declared with the Q_INVOKABLE modifier are made available through the meta-object system. \sa Q_ARG(), constructor() */ QObject *QMetaObject::newInstance(QGenericArgument val0, QGenericArgument val1, QGenericArgument val2, QGenericArgument val3, QGenericArgument val4, QGenericArgument val5, QGenericArgument val6, QGenericArgument val7, QGenericArgument val8, QGenericArgument val9) const { QByteArray constructorName = className(); { int idx = constructorName.lastIndexOf(':'); if (idx != -1) constructorName.remove(0, idx+1); // remove qualified part } QVarLengthArray sig; sig.append(constructorName.constData(), constructorName.length()); sig.append('('); enum { MaximumParamCount = 10 }; const char *typeNames[] = {val0.name(), val1.name(), val2.name(), val3.name(), val4.name(), val5.name(), val6.name(), val7.name(), val8.name(), val9.name()}; int paramCount; for (paramCount = 0; paramCount < MaximumParamCount; ++paramCount) { int len = qstrlen(typeNames[paramCount]); if (len <= 0) break; sig.append(typeNames[paramCount], len); sig.append(','); } if (paramCount == 0) sig.append(')'); // no parameters else sig[sig.size() - 1] = ')'; sig.append('\0'); int idx = indexOfConstructor(sig.constData()); if (idx < 0) { QByteArray norm = QMetaObject::normalizedSignature(sig.constData()); idx = indexOfConstructor(norm.constData()); } if (idx < 0) return 0; QVariant ret(QMetaType::QObjectStar, (void*)0); void *param[] = {ret.data(), val0.data(), val1.data(), val2.data(), val3.data(), val4.data(), val5.data(), val6.data(), val7.data(), val8.data(), val9.data()}; if (static_metacall(CreateInstance, idx, param) >= 0) return 0; return *reinterpret_cast(param[0]); } /*! \internal */ int QMetaObject::static_metacall(Call cl, int idx, void **argv) const { if (priv(d.data)->revision < 2) return 0; const QMetaObjectExtraData *extra = (const QMetaObjectExtraData*)(d.extradata); if (!extra || !extra->static_metacall) return 0; return extra->static_metacall(cl, idx, argv); } /*! \internal */ int QMetaObject::metacall(QObject *object, Call cl, int idx, void **argv) { if (QMetaObject *mo = object->d_ptr->metaObject) return static_cast(mo)->metaCall(cl, idx, argv); else return object->qt_metacall(cl, idx, argv); } /*! \fn const char *QMetaObject::className() const Returns the class name. \sa superClass() */ /*! \fn QMetaObject *QMetaObject::superClass() const Returns the meta-object of the superclass, or 0 if there is no such object. \sa className() */ /*! \internal Returns \a obj if object \a obj inherits from this meta-object; otherwise returns 0. */ QObject *QMetaObject::cast(QObject *obj) const { if (obj) { const QMetaObject *m = obj->metaObject(); do { if (m == this) return const_cast(obj); } while ((m = m->d.superdata)); } return 0; } #ifndef QT_NO_TRANSLATION /*! \internal */ QString QMetaObject::tr(const char *s, const char *c) const { return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::CodecForTr); } /*! \internal */ QString QMetaObject::tr(const char *s, const char *c, int n) const { return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::CodecForTr, n); } /*! \internal */ QString QMetaObject::trUtf8(const char *s, const char *c) const { return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::UnicodeUTF8); } /*! \internal */ QString QMetaObject::trUtf8(const char *s, const char *c, int n) const { return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::UnicodeUTF8, n); } #endif // QT_NO_TRANSLATION /*! Returns the method offset for this class; i.e. the index position of this class's first member function. The offset is the sum of all the methods in the class's superclasses (which is always positive since QObject has the deleteLater() slot and a destroyed() signal). \sa method(), methodCount(), indexOfMethod() */ int QMetaObject::methodOffset() const { int offset = 0; const QMetaObject *m = d.superdata; while (m) { offset += priv(m->d.data)->methodCount; m = m->d.superdata; } return offset; } /*! Returns the enumerator offset for this class; i.e. the index position of this class's first enumerator. If the class has no superclasses with enumerators, the offset is 0; otherwise the offset is the sum of all the enumerators in the class's superclasses. \sa enumerator(), enumeratorCount(), indexOfEnumerator() */ int QMetaObject::enumeratorOffset() const { int offset = 0; const QMetaObject *m = d.superdata; while (m) { offset += priv(m->d.data)->enumeratorCount; m = m->d.superdata; } return offset; } /*! Returns the property offset for this class; i.e. the index position of this class's first property. The offset is the sum of all the properties in the class's superclasses (which is always positive since QObject has the name() property). \sa property(), propertyCount(), indexOfProperty() */ int QMetaObject::propertyOffset() const { int offset = 0; const QMetaObject *m = d.superdata; while (m) { offset += priv(m->d.data)->propertyCount; m = m->d.superdata; } return offset; } /*! Returns the class information offset for this class; i.e. the index position of this class's first class information item. If the class has no superclasses with class information, the offset is 0; otherwise the offset is the sum of all the class information items in the class's superclasses. \sa classInfo(), classInfoCount(), indexOfClassInfo() */ int QMetaObject::classInfoOffset() const { int offset = 0; const QMetaObject *m = d.superdata; while (m) { offset += priv(m->d.data)->classInfoCount; m = m->d.superdata; } return offset; } /*! \since 4.5 Returns the number of constructors in this class. \sa constructor(), indexOfConstructor() */ int QMetaObject::constructorCount() const { if (priv(d.data)->revision < 2) return 0; return priv(d.data)->constructorCount; } /*! Returns the number of methods in this class, including the number of properties provided by each base class. These include signals and slots as well as normal member functions. Use code like the following to obtain a QStringList containing the methods specific to a given class: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp methodCount \sa method(), methodOffset(), indexOfMethod() */ int QMetaObject::methodCount() const { int n = priv(d.data)->methodCount; const QMetaObject *m = d.superdata; while (m) { n += priv(m->d.data)->methodCount; m = m->d.superdata; } return n; } /*! Returns the number of enumerators in this class. \sa enumerator(), enumeratorOffset(), indexOfEnumerator() */ int QMetaObject::enumeratorCount() const { int n = priv(d.data)->enumeratorCount; const QMetaObject *m = d.superdata; while (m) { n += priv(m->d.data)->enumeratorCount; m = m->d.superdata; } return n; } /*! Returns the number of properties in this class, including the number of properties provided by each base class. Use code like the following to obtain a QStringList containing the properties specific to a given class: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp propertyCount \sa property(), propertyOffset(), indexOfProperty() */ int QMetaObject::propertyCount() const { int n = priv(d.data)->propertyCount; const QMetaObject *m = d.superdata; while (m) { n += priv(m->d.data)->propertyCount; m = m->d.superdata; } return n; } /*! Returns the number of items of class information in this class. \sa classInfo(), classInfoOffset(), indexOfClassInfo() */ int QMetaObject::classInfoCount() const { int n = priv(d.data)->classInfoCount; const QMetaObject *m = d.superdata; while (m) { n += priv(m->d.data)->classInfoCount; m = m->d.superdata; } return n; } /** \internal * helper class for indexOf{Method,Slot,Signal}, returns the relative index of the method within * the baseObject * \a MethodType might be MethodSignal or MethodSlot, or 0 to match everything. */ template static inline int indexOfMethodRelative(const QMetaObject **baseObject, const char *method, bool normalizeStringData) { const QMetaObject *m; for (m = *baseObject; m; m = *baseObject = m->d.superdata) { const QMetaObject *const m = *baseObject; int i = (MethodType == MethodSignal && priv(m->d.data)->revision >= 4) ? (priv(m->d.data)->signalCount - 1) : (priv(m->d.data)->methodCount - 1); if (i < 0) continue; const int end = (MethodType == MethodSlot && priv(m->d.data)->revision >= 4) ? (priv(m->d.data)->signalCount) : 0; if (!normalizeStringData) { for (; i >= end; --i) { if ((MethodType == 0 || (m->d.data[priv(m->d.data)->methodData + 5*i + 4] & MethodTypeMask) == MethodType) && strcmp(method, m->d.stringdata + m->d.data[priv(m->d.data)->methodData + 5*i]) == 0) return i; } } else if (priv(m->d.data)->revision < 5) { const char *stringdata = (m->d.stringdata + m->d.data[priv(m->d.data)->methodData + 5 * i]); const QByteArray normalizedSignature = QMetaObject::normalizedSignature(stringdata); for (; i >= end; --i) { if ((MethodType == 0|| (m->d.data[priv(m->d.data)->methodData + 5*i + 4] & MethodTypeMask) == MethodType) && normalizedSignature == method) return i; } } } return -1; } /*! \since 4.5 Finds \a constructor and returns its index; otherwise returns -1. Note that the \a constructor has to be in normalized form, as returned by normalizedSignature(). \sa constructor(), constructorCount(), normalizedSignature() */ int QMetaObject::indexOfConstructor(const char *constructor) const { if (priv(d.data)->revision < 2) return -1; for (int i = priv(d.data)->constructorCount-1; i >= 0; --i) { if (strcmp(constructor, d.stringdata + d.data[priv(d.data)->constructorData + 5*i]) == 0) { return i; } } return -1; } /*! Finds \a method and returns its index; otherwise returns -1. Note that the \a method has to be in normalized form, as returned by normalizedSignature(). \sa method(), methodCount(), methodOffset(), normalizedSignature() */ int QMetaObject::indexOfMethod(const char *method) const { const QMetaObject *m = this; int i = indexOfMethodRelative<0>(&m, method, false); if (i < 0) { m = this; i = indexOfMethodRelative<0>(&m, method, true); } if (i >= 0) i += m->methodOffset(); return i; } /*! Finds \a signal and returns its index; otherwise returns -1. This is the same as indexOfMethod(), except that it will return -1 if the method exists but isn't a signal. Note that the \a signal has to be in normalized form, as returned by normalizedSignature(). \sa indexOfMethod(), normalizedSignature(), method(), methodCount(), methodOffset() */ int QMetaObject::indexOfSignal(const char *signal) const { const QMetaObject *m = this; int i = QMetaObjectPrivate::indexOfSignalRelative(&m, signal, false); if (i < 0) { m = this; i = QMetaObjectPrivate::indexOfSignalRelative(&m, signal, true); } if (i >= 0) i += m->methodOffset(); return i; } /*! \internal Same as QMetaObject::indexOfSignal, but the result is the local offset to the base object. \a baseObject will be adjusted to the enclosing QMetaObject, or 0 if the signal is not found */ int QMetaObjectPrivate::indexOfSignalRelative(const QMetaObject **baseObject, const char *signal, bool normalizeStringData) { int i = indexOfMethodRelative(baseObject, signal, normalizeStringData); #ifndef QT_NO_DEBUG const QMetaObject *m = *baseObject; if (i >= 0 && m && m->d.superdata) { int conflict = m->d.superdata->indexOfMethod(signal); if (conflict >= 0) qWarning("QMetaObject::indexOfSignal: signal %s from %s redefined in %s", signal, m->d.superdata->d.stringdata, m->d.stringdata); } #endif return i; } /*! Finds \a slot and returns its index; otherwise returns -1. This is the same as indexOfMethod(), except that it will return -1 if the method exists but isn't a slot. \sa indexOfMethod(), method(), methodCount(), methodOffset() */ int QMetaObject::indexOfSlot(const char *slot) const { int i = QMetaObjectPrivate::indexOfSlot(this, slot, false); if (i < 0) i = QMetaObjectPrivate::indexOfSlot(this, slot, true); return i; } int QMetaObjectPrivate::indexOfSlot(const QMetaObject *m, const char *slot, bool normalizeStringData) { int i = indexOfMethodRelative(&m, slot, normalizeStringData); if (i >= 0) i += m->methodOffset(); return i; } static const QMetaObject *QMetaObject_findMetaObject(const QMetaObject *self, const char *name) { while (self) { if (strcmp(self->d.stringdata, name) == 0) return self; if (self->d.extradata) { #ifdef Q_NO_DATA_RELOCATION const QMetaObjectAccessor *e; Q_ASSERT(priv(self->d.data)->revision >= 2); #else const QMetaObject **e; if (priv(self->d.data)->revision < 2) { e = (const QMetaObject**)(self->d.extradata); } else #endif { const QMetaObjectExtraData *extra = (const QMetaObjectExtraData*)(self->d.extradata); e = extra->objects; } if (e) { while (*e) { #ifdef Q_NO_DATA_RELOCATION if (const QMetaObject *m =QMetaObject_findMetaObject(&((*e)()), name)) #else if (const QMetaObject *m =QMetaObject_findMetaObject((*e), name)) #endif return m; ++e; } } } self = self->d.superdata; } return self; } /*! Finds enumerator \a name and returns its index; otherwise returns -1. \sa enumerator(), enumeratorCount(), enumeratorOffset() */ int QMetaObject::indexOfEnumerator(const char *name) const { int i = -1; const QMetaObject *m = this; while (m && i < 0) { for (i = priv(m->d.data)->enumeratorCount-1; i >= 0; --i) if (strcmp(name, m->d.stringdata + m->d.data[priv(m->d.data)->enumeratorData + 4*i]) == 0) { i += m->enumeratorOffset(); break; } m = m->d.superdata; } return i; } /*! Finds property \a name and returns its index; otherwise returns -1. \sa property(), propertyCount(), propertyOffset() */ int QMetaObject::indexOfProperty(const char *name) const { int i = -1; const QMetaObject *m = this; while (m && i < 0) { for (i = priv(m->d.data)->propertyCount-1; i >= 0; --i) if (strcmp(name, m->d.stringdata + m->d.data[priv(m->d.data)->propertyData + 3*i]) == 0) { i += m->propertyOffset(); break; } m = m->d.superdata; } if (i == -1 && priv(this->d.data)->revision >= 3 && (priv(this->d.data)->flags & DynamicMetaObject)){ QAbstractDynamicMetaObject *me = const_cast(static_cast(this)); i = me->createProperty(name, 0); } return i; } /*! Finds class information item \a name and returns its index; otherwise returns -1. \sa classInfo(), classInfoCount(), classInfoOffset() */ int QMetaObject::indexOfClassInfo(const char *name) const { int i = -1; const QMetaObject *m = this; while (m && i < 0) { for (i = priv(m->d.data)->classInfoCount-1; i >= 0; --i) if (strcmp(name, m->d.stringdata + m->d.data[priv(m->d.data)->classInfoData + 2*i]) == 0) { i += m->classInfoOffset(); break; } m = m->d.superdata; } return i; } /*! \since 4.5 Returns the meta-data for the constructor with the given \a index. \sa constructorCount(), newInstance() */ QMetaMethod QMetaObject::constructor(int index) const { int i = index; QMetaMethod result; if (priv(d.data)->revision >= 2 && i >= 0 && i < priv(d.data)->constructorCount) { result.mobj = this; result.handle = priv(d.data)->constructorData + 5*i; } return result; } /*! Returns the meta-data for the method with the given \a index. \sa methodCount(), methodOffset(), indexOfMethod() */ QMetaMethod QMetaObject::method(int index) const { int i = index; i -= methodOffset(); if (i < 0 && d.superdata) return d.superdata->method(index); QMetaMethod result; if (i >= 0 && i < priv(d.data)->methodCount) { result.mobj = this; result.handle = priv(d.data)->methodData + 5*i; } return result; } /*! Returns the meta-data for the enumerator with the given \a index. \sa enumeratorCount(), enumeratorOffset(), indexOfEnumerator() */ QMetaEnum QMetaObject::enumerator(int index) const { int i = index; i -= enumeratorOffset(); if (i < 0 && d.superdata) return d.superdata->enumerator(index); QMetaEnum result; if (i >= 0 && i < priv(d.data)->enumeratorCount) { result.mobj = this; result.handle = priv(d.data)->enumeratorData + 4*i; } return result; } /*! Returns the meta-data for the property with the given \a index. If no such property exists, a null QMetaProperty is returned. \sa propertyCount(), propertyOffset(), indexOfProperty() */ QMetaProperty QMetaObject::property(int index) const { int i = index; i -= propertyOffset(); if (i < 0 && d.superdata) return d.superdata->property(index); QMetaProperty result; if (i >= 0 && i < priv(d.data)->propertyCount) { int handle = priv(d.data)->propertyData + 3*i; int flags = d.data[handle + 2]; const char *type = d.stringdata + d.data[handle + 1]; result.mobj = this; result.handle = handle; result.idx = i; if (flags & EnumOrFlag) { result.menum = enumerator(indexOfEnumerator(type)); if (!result.menum.isValid()) { QByteArray enum_name = type; QByteArray scope_name = d.stringdata; int s = enum_name.lastIndexOf("::"); if (s > 0) { scope_name = enum_name.left(s); enum_name = enum_name.mid(s + 2); } const QMetaObject *scope = 0; if (scope_name == "Qt") scope = &QObject::staticQtMetaObject; else scope = QMetaObject_findMetaObject(this, scope_name); if (scope) result.menum = scope->enumerator(scope->indexOfEnumerator(enum_name)); } } } return result; } /*! \since 4.2 Returns the property that has the \c USER flag set to true. \sa QMetaProperty::isUser() */ QMetaProperty QMetaObject::userProperty() const { const int propCount = propertyCount(); for (int i = propCount - 1; i >= 0; --i) { const QMetaProperty prop = property(i); if (prop.isUser()) return prop; } return QMetaProperty(); } /*! Returns the meta-data for the item of class information with the given \a index. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 0 \sa classInfoCount(), classInfoOffset(), indexOfClassInfo() */ QMetaClassInfo QMetaObject::classInfo(int index) const { int i = index; i -= classInfoOffset(); if (i < 0 && d.superdata) return d.superdata->classInfo(index); QMetaClassInfo result; if (i >= 0 && i < priv(d.data)->classInfoCount) { result.mobj = this; result.handle = priv(d.data)->classInfoData + 2*i; } return result; } /*! Returns true if the \a signal and \a method arguments are compatible; otherwise returns false. Both \a signal and \a method are expected to be normalized. \sa normalizedSignature() */ bool QMetaObject::checkConnectArgs(const char *signal, const char *method) { const char *s1 = signal; const char *s2 = method; while (*s1++ != '(') { } // scan to first '(' while (*s2++ != '(') { } if (*s2 == ')' || qstrcmp(s1,s2) == 0) // method has no args or return true; // exact match int s1len = qstrlen(s1); int s2len = qstrlen(s2); if (s2len < s1len && strncmp(s1,s2,s2len-1)==0 && s1[s2len-1]==',') return true; // method has less args return false; } static void qRemoveWhitespace(const char *s, char *d) { char last = 0; while (*s && is_space(*s)) s++; while (*s) { while (*s && !is_space(*s)) last = *d++ = *s++; while (*s && is_space(*s)) s++; if (*s && ((is_ident_char(*s) && is_ident_char(last)) || ((*s == ':') && (last == '<')))) { last = *d++ = ' '; } } *d = '\0'; } static char *qNormalizeType(char *d, int &templdepth, QByteArray &result) { const char *t = d; while (*d && (templdepth || (*d != ',' && *d != ')'))) { if (*d == '<') ++templdepth; if (*d == '>') --templdepth; ++d; } if (strncmp("void", t, d - t) != 0) result += normalizeTypeInternal(t, d); return d; } /*! \since 4.2 Normalizes a \a type. See QMetaObject::normalizedSignature() for a description on how Qt normalizes. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 1 \sa normalizedSignature() */ QByteArray QMetaObject::normalizedType(const char *type) { QByteArray result; if (!type || !*type) return result; QVarLengthArray stackbuf(qstrlen(type) + 1); qRemoveWhitespace(type, stackbuf.data()); int templdepth = 0; qNormalizeType(stackbuf.data(), templdepth, result); return result; } /*! Normalizes the signature of the given \a method. Qt uses normalized signatures to decide whether two given signals and slots are compatible. Normalization reduces whitespace to a minimum, moves 'const' to the front where appropriate, removes 'const' from value types and replaces const references with values. \sa checkConnectArgs(), normalizedType() */ QByteArray QMetaObject::normalizedSignature(const char *method) { QByteArray result; if (!method || !*method) return result; int len = int(strlen(method)); QVarLengthArray stackbuf(len + 1); char *d = stackbuf.data(); qRemoveWhitespace(method, d); result.reserve(len); int argdepth = 0; int templdepth = 0; while (*d) { if (argdepth == 1) d = qNormalizeType(d, templdepth, result); if (*d == '(') ++argdepth; if (*d == ')') --argdepth; result += *d++; } return result; } enum { MaximumParamCount = 11 }; // up to 10 arguments + 1 return value /*! Invokes the \a member (a signal or a slot name) on the object \a obj. Returns true if the member could be invoked. Returns false if there is no such member or the parameters did not match. The invocation can be either synchronous or asynchronous, depending on \a type: \list \o If \a type is Qt::DirectConnection, the member will be invoked immediately. \o If \a type is Qt::QueuedConnection, a QEvent will be sent and the member is invoked as soon as the application enters the main event loop. \o If \a type is Qt::BlockingQueuedConnection, the method will be invoked in the same way as for Qt::QueuedConnection, except that the current thread will block until the event is delivered. Using this connection type to communicate between objects in the same thread will lead to deadlocks. \o If \a type is Qt::AutoConnection, the member is invoked synchronously if \a obj lives in the same thread as the caller; otherwise it will invoke the member asynchronously. \endlist The return value of the \a member function call is placed in \a ret. If the invocation is asynchronous, the return value cannot be evaluated. You can pass up to ten arguments (\a val0, \a val1, \a val2, \a val3, \a val4, \a val5, \a val6, \a val7, \a val8, and \a val9) to the \a member function. QGenericArgument and QGenericReturnArgument are internal helper classes. Because signals and slots can be dynamically invoked, you must enclose the arguments using the Q_ARG() and Q_RETURN_ARG() macros. Q_ARG() takes a type name and a const reference of that type; Q_RETURN_ARG() takes a type name and a non-const reference. You only need to pass the name of the signal or slot to this function, not the entire signature. For example, to asynchronously invoke the \l{QPushButton::animateClick()}{animateClick()} slot on a QPushButton, use the following code: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 2 With asynchronous method invocations, the parameters must be of types that are known to Qt's meta-object system, because Qt needs to copy the arguments to store them in an event behind the scenes. If you try to use a queued connection and get the error message \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 3 call qRegisterMetaType() to register the data type before you call invokeMethod(). To synchronously invoke the \c compute(QString, int, double) slot on some arbitrary object \c obj retrieve its return value: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 4 If the "compute" slot does not take exactly one QString, one int and one double in the specified order, the call will fail. \sa Q_ARG(), Q_RETURN_ARG(), qRegisterMetaType(), QMetaMethod::invoke() */ bool QMetaObject::invokeMethod(QObject *obj, const char *member, Qt::ConnectionType type, QGenericReturnArgument ret, QGenericArgument val0, QGenericArgument val1, QGenericArgument val2, QGenericArgument val3, QGenericArgument val4, QGenericArgument val5, QGenericArgument val6, QGenericArgument val7, QGenericArgument val8, QGenericArgument val9) { if (!obj) return false; QVarLengthArray sig; int len = qstrlen(member); if (len <= 0) return false; sig.append(member, len); sig.append('('); const char *typeNames[] = {ret.name(), val0.name(), val1.name(), val2.name(), val3.name(), val4.name(), val5.name(), val6.name(), val7.name(), val8.name(), val9.name()}; int paramCount; for (paramCount = 1; paramCount < MaximumParamCount; ++paramCount) { len = qstrlen(typeNames[paramCount]); if (len <= 0) break; sig.append(typeNames[paramCount], len); sig.append(','); } if (paramCount == 1) sig.append(')'); // no parameters else sig[sig.size() - 1] = ')'; sig.append('\0'); int idx = obj->metaObject()->indexOfMethod(sig.constData()); if (idx < 0) { QByteArray norm = QMetaObject::normalizedSignature(sig.constData()); idx = obj->metaObject()->indexOfMethod(norm.constData()); } if (idx < 0 || idx >= obj->metaObject()->methodCount()) { qWarning("QMetaObject::invokeMethod: No such method %s::%s", obj->metaObject()->className(), sig.constData()); return false; } QMetaMethod method = obj->metaObject()->method(idx); return method.invoke(obj, type, ret, val0, val1, val2, val3, val4, val5, val6, val7, val8, val9); } /*! \fn bool QMetaObject::invokeMethod(QObject *obj, const char *member, QGenericReturnArgument ret, QGenericArgument val0 = QGenericArgument(0), QGenericArgument val1 = QGenericArgument(), QGenericArgument val2 = QGenericArgument(), QGenericArgument val3 = QGenericArgument(), QGenericArgument val4 = QGenericArgument(), QGenericArgument val5 = QGenericArgument(), QGenericArgument val6 = QGenericArgument(), QGenericArgument val7 = QGenericArgument(), QGenericArgument val8 = QGenericArgument(), QGenericArgument val9 = QGenericArgument()); \overload invokeMethod() This overload always invokes the member using the connection type Qt::AutoConnection. */ /*! \fn bool QMetaObject::invokeMethod(QObject *obj, const char *member, Qt::ConnectionType type, QGenericArgument val0 = QGenericArgument(0), QGenericArgument val1 = QGenericArgument(), QGenericArgument val2 = QGenericArgument(), QGenericArgument val3 = QGenericArgument(), QGenericArgument val4 = QGenericArgument(), QGenericArgument val5 = QGenericArgument(), QGenericArgument val6 = QGenericArgument(), QGenericArgument val7 = QGenericArgument(), QGenericArgument val8 = QGenericArgument(), QGenericArgument val9 = QGenericArgument()) \overload invokeMethod() This overload can be used if the return value of the member is of no interest. */ /*! \fn bool QMetaObject::invokeMethod(QObject *obj, const char *member, QGenericArgument val0 = QGenericArgument(0), QGenericArgument val1 = QGenericArgument(), QGenericArgument val2 = QGenericArgument(), QGenericArgument val3 = QGenericArgument(), QGenericArgument val4 = QGenericArgument(), QGenericArgument val5 = QGenericArgument(), QGenericArgument val6 = QGenericArgument(), QGenericArgument val7 = QGenericArgument(), QGenericArgument val8 = QGenericArgument(), QGenericArgument val9 = QGenericArgument()) \overload invokeMethod() This overload invokes the member using the connection type Qt::AutoConnection and ignores return values. */ /*! \class QMetaMethod \brief The QMetaMethod class provides meta-data about a member function. \ingroup objectmodel A QMetaMethod has a methodType(), a signature(), a list of parameterTypes() and parameterNames(), a return typeName(), a tag(), and an access() specifier. You can use invoke() to invoke the method on an arbitrary QObject. \sa QMetaObject, QMetaEnum, QMetaProperty, {Qt's Property System} */ /*! \enum QMetaMethod::Attributes \internal \value Compatibility \value Cloned \value Scriptable */ /*! \fn const QMetaObject *QMetaMethod::enclosingMetaObject() const \internal */ /*! \enum QMetaMethod::MethodType \value Method The function is a plain member function. \value Signal The function is a signal. \value Slot The function is a slot. \value Constructor The function is a constructor. */ /*! \fn QMetaMethod::QMetaMethod() \internal */ /*! Returns the signature of this method (e.g., \c{setValue(double)}). \sa parameterTypes(), parameterNames() */ const char *QMetaMethod::signature() const { if (!mobj) return 0; return mobj->d.stringdata + mobj->d.data[handle]; } /*! Returns a list of parameter types. \sa parameterNames(), signature() */ QList QMetaMethod::parameterTypes() const { QList list; if (!mobj) return list; const char *signature = mobj->d.stringdata + mobj->d.data[handle]; while (*signature && *signature != '(') ++signature; while (*signature && *signature != ')' && *++signature != ')') { const char *begin = signature; int level = 0; while (*signature && (level > 0 || *signature != ',') && *signature != ')') { if (*signature == '<') ++level; else if (*signature == '>') --level; ++signature; } list += QByteArray(begin, signature - begin); } return list; } /*! Returns a list of parameter names. \sa parameterTypes(), signature() */ QList QMetaMethod::parameterNames() const { QList list; if (!mobj) return list; const char *names = mobj->d.stringdata + mobj->d.data[handle + 1]; if (*names == 0) { // do we have one or zero arguments? const char *signature = mobj->d.stringdata + mobj->d.data[handle]; while (*signature && *signature != '(') ++signature; if (*++signature != ')') list += QByteArray(); } else { --names; do { const char *begin = ++names; while (*names && *names != ',') ++names; list += QByteArray(begin, names - begin); } while (*names); } return list; } /*! Returns the return type of this method, or an empty string if the return type is \e void. */ const char *QMetaMethod::typeName() const { if (!mobj) return 0; return mobj->d.stringdata + mobj->d.data[handle + 2]; } /*! Returns the tag associated with this method. Tags are special macros recognized by \c moc that make it possible to add extra information about a method. For the moment, \c moc doesn't support any special tags. */ const char *QMetaMethod::tag() const { if (!mobj) return 0; return mobj->d.stringdata + mobj->d.data[handle + 3]; } /*! \internal */ int QMetaMethod::attributes() const { if (!mobj) return false; return ((mobj->d.data[handle + 4])>>4); } /*! \since 4.6 Returns this method's index. */ int QMetaMethod::methodIndex() const { if (!mobj) return -1; return ((handle - priv(mobj->d.data)->methodData) / 5) + mobj->methodOffset(); } /*! Returns the access specification of this method (private, protected, or public). Signals are always protected, meaning that you can only emit them from the class or from a subclass. \sa methodType() */ QMetaMethod::Access QMetaMethod::access() const { if (!mobj) return Private; return (QMetaMethod::Access)(mobj->d.data[handle + 4] & AccessMask); } /*! Returns the type of this method (signal, slot, or method). \sa access() */ QMetaMethod::MethodType QMetaMethod::methodType() const { if (!mobj) return QMetaMethod::Method; return (QMetaMethod::MethodType)((mobj->d.data[handle + 4] & MethodTypeMask)>>2); } /*! Invokes this method on the object \a object. Returns true if the member could be invoked. Returns false if there is no such member or the parameters did not match. The invocation can be either synchronous or asynchronous, depending on the \a connectionType: \list \o If \a connectionType is Qt::DirectConnection, the member will be invoked immediately. \o If \a connectionType is Qt::QueuedConnection, a QEvent will be posted and the member is invoked as soon as the application enters the main event loop. \o If \a connectionType is Qt::AutoConnection, the member is invoked synchronously if \a object lives in the same thread as the caller; otherwise it will invoke the member asynchronously. \endlist The return value of this method call is placed in \a returnValue. If the invocation is asynchronous, the return value cannot be evaluated. You can pass up to ten arguments (\a val0, \a val1, \a val2, \a val3, \a val4, \a val5, \a val6, \a val7, \a val8, and \a val9) to this method call. QGenericArgument and QGenericReturnArgument are internal helper classes. Because signals and slots can be dynamically invoked, you must enclose the arguments using the Q_ARG() and Q_RETURN_ARG() macros. Q_ARG() takes a type name and a const reference of that type; Q_RETURN_ARG() takes a type name and a non-const reference. To asynchronously invoke the \l{QPushButton::animateClick()}{animateClick()} slot on a QPushButton: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 6 With asynchronous method invocations, the parameters must be of types that are known to Qt's meta-object system, because Qt needs to copy the arguments to store them in an event behind the scenes. If you try to use a queued connection and get the error message \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 7 call qRegisterMetaType() to register the data type before you call QMetaMethod::invoke(). To synchronously invoke the \c compute(QString, int, double) slot on some arbitrary object \c obj retrieve its return value: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 8 QMetaObject::normalizedSignature() is used here to ensure that the format of the signature is what invoke() expects. E.g. extra whitespace is removed. If the "compute" slot does not take exactly one QString, one int and one double in the specified order, the call will fail. \sa Q_ARG(), Q_RETURN_ARG(), qRegisterMetaType(), QMetaObject::invokeMethod() */ bool QMetaMethod::invoke(QObject *object, Qt::ConnectionType connectionType, QGenericReturnArgument returnValue, QGenericArgument val0, QGenericArgument val1, QGenericArgument val2, QGenericArgument val3, QGenericArgument val4, QGenericArgument val5, QGenericArgument val6, QGenericArgument val7, QGenericArgument val8, QGenericArgument val9) const { if (!object || !mobj) return false; // check return type if (returnValue.data()) { const char *retType = typeName(); if (qstrcmp(returnValue.name(), retType) != 0) { // normalize the return value as well // the trick here is to make a function signature out of the return type // so that we can call normalizedSignature() and avoid duplicating code QByteArray unnormalized; int len = qstrlen(returnValue.name()); unnormalized.reserve(len + 3); unnormalized = "_("; // the function is called "_" unnormalized.append(returnValue.name()); unnormalized.append(')'); QByteArray normalized = QMetaObject::normalizedSignature(unnormalized.constData()); normalized.truncate(normalized.length() - 1); // drop the ending ')' if (qstrcmp(normalized.constData() + 2, retType) != 0) return false; } } // check argument count (we don't allow invoking a method if given too few arguments) const char *typeNames[] = { returnValue.name(), val0.name(), val1.name(), val2.name(), val3.name(), val4.name(), val5.name(), val6.name(), val7.name(), val8.name(), val9.name() }; int paramCount; for (paramCount = 1; paramCount < MaximumParamCount; ++paramCount) { if (qstrlen(typeNames[paramCount]) <= 0) break; } int metaMethodArgumentCount = 0; { // based on QMetaObject::parameterNames() const char *names = mobj->d.stringdata + mobj->d.data[handle + 1]; if (*names == 0) { // do we have one or zero arguments? const char *signature = mobj->d.stringdata + mobj->d.data[handle]; while (*signature && *signature != '(') ++signature; if (*++signature != ')') ++metaMethodArgumentCount; } else { --names; do { ++names; while (*names && *names != ',') ++names; ++metaMethodArgumentCount; } while (*names); } } if (paramCount <= metaMethodArgumentCount) return false; // check connection type QThread *currentThread = QThread::currentThread(); QThread *objectThread = object->thread(); if (connectionType == Qt::AutoConnection) { connectionType = currentThread == objectThread ? Qt::DirectConnection : Qt::QueuedConnection; } // invoke! void *param[] = { returnValue.data(), val0.data(), val1.data(), val2.data(), val3.data(), val4.data(), val5.data(), val6.data(), val7.data(), val8.data(), val9.data() }; // recompute the methodIndex by reversing the arithmetic in QMetaObject::property() int methodIndex = ((handle - priv(mobj->d.data)->methodData) / 5) + mobj->methodOffset(); if (connectionType == Qt::DirectConnection) { return QMetaObject::metacall(object, QMetaObject::InvokeMetaMethod, methodIndex, param) < 0; } else { if (returnValue.data()) { qWarning("QMetaMethod::invoke: Unable to invoke methods with return values in " "queued connections"); return false; } int nargs = 1; // include return type void **args = (void **) qMalloc(paramCount * sizeof(void *)); Q_CHECK_PTR(args); int *types = (int *) qMalloc(paramCount * sizeof(int)); Q_CHECK_PTR(types); types[0] = 0; // return type args[0] = 0; for (int i = 1; i < paramCount; ++i) { types[i] = QMetaType::type(typeNames[i]); if (types[i]) { args[i] = QMetaType::construct(types[i], param[i]); ++nargs; } else if (param[i]) { qWarning("QMetaMethod::invoke: Unable to handle unregistered datatype '%s'", typeNames[i]); for (int x = 1; x < i; ++x) { if (types[x] && args[x]) QMetaType::destroy(types[x], args[x]); } qFree(types); qFree(args); return false; } } if (connectionType == Qt::QueuedConnection) { QCoreApplication::postEvent(object, new QMetaCallEvent(methodIndex, 0, -1, nargs, types, args)); } else { if (currentThread == objectThread) { qWarning("QMetaMethod::invoke: Dead lock detected in " "BlockingQueuedConnection: Receiver is %s(%p)", mobj->className(), object); } // blocking queued connection #ifdef QT_NO_THREAD QCoreApplication::postEvent(object, new QMetaCallEvent(methodIndex, 0, -1, nargs, types, args)); #else QSemaphore semaphore; QCoreApplication::postEvent(object, new QMetaCallEvent(methodIndex, 0, -1, nargs, types, args, &semaphore)); semaphore.acquire(); #endif // QT_NO_THREAD } } return true; } /*! \fn bool QMetaMethod::invoke(QObject *object, QGenericReturnArgument returnValue, QGenericArgument val0 = QGenericArgument(0), QGenericArgument val1 = QGenericArgument(), QGenericArgument val2 = QGenericArgument(), QGenericArgument val3 = QGenericArgument(), QGenericArgument val4 = QGenericArgument(), QGenericArgument val5 = QGenericArgument(), QGenericArgument val6 = QGenericArgument(), QGenericArgument val7 = QGenericArgument(), QGenericArgument val8 = QGenericArgument(), QGenericArgument val9 = QGenericArgument()) const \overload invoke() This overload always invokes this method using the connection type Qt::AutoConnection. */ /*! \fn bool QMetaMethod::invoke(QObject *object, Qt::ConnectionType connectionType, QGenericArgument val0 = QGenericArgument(0), QGenericArgument val1 = QGenericArgument(), QGenericArgument val2 = QGenericArgument(), QGenericArgument val3 = QGenericArgument(), QGenericArgument val4 = QGenericArgument(), QGenericArgument val5 = QGenericArgument(), QGenericArgument val6 = QGenericArgument(), QGenericArgument val7 = QGenericArgument(), QGenericArgument val8 = QGenericArgument(), QGenericArgument val9 = QGenericArgument()) const \overload invoke() This overload can be used if the return value of the member is of no interest. */ /*! \fn bool QMetaMethod::invoke(QObject *object, QGenericArgument val0 = QGenericArgument(0), QGenericArgument val1 = QGenericArgument(), QGenericArgument val2 = QGenericArgument(), QGenericArgument val3 = QGenericArgument(), QGenericArgument val4 = QGenericArgument(), QGenericArgument val5 = QGenericArgument(), QGenericArgument val6 = QGenericArgument(), QGenericArgument val7 = QGenericArgument(), QGenericArgument val8 = QGenericArgument(), QGenericArgument val9 = QGenericArgument()) const \overload invoke() This overload invokes this method using the connection type Qt::AutoConnection and ignores return values. */ /*! \class QMetaEnum \brief The QMetaEnum class provides meta-data about an enumerator. \ingroup objectmodel Use name() for the enumerator's name. The enumerator's keys (names of each enumerated item) are returned by key(); use keyCount() to find the number of keys. isFlag() returns whether the enumerator is meant to be used as a flag, meaning that its values can be combined using the OR operator. The conversion functions keyToValue(), valueToKey(), keysToValue(), and valueToKeys() allow conversion between the integer representation of an enumeration or set value and its literal representation. The scope() function returns the class scope this enumerator was declared in. \sa QMetaObject, QMetaMethod, QMetaProperty */ /*! \fn bool QMetaEnum::isValid() const Returns true if this enum is valid (has a name); otherwise returns false. \sa name() */ /*! \fn const QMetaObject *QMetaEnum::enclosingMetaObject() const \internal */ /*! \fn QMetaEnum::QMetaEnum() \internal */ /*! Returns the name of the enumerator (without the scope). For example, the Qt::AlignmentFlag enumeration has \c AlignmentFlag as the name and \l Qt as the scope. \sa isValid(), scope() */ const char *QMetaEnum::name() const { if (!mobj) return 0; return mobj->d.stringdata + mobj->d.data[handle]; } /*! Returns the number of keys. \sa key() */ int QMetaEnum::keyCount() const { if (!mobj) return 0; return mobj->d.data[handle + 2]; } /*! Returns the key with the given \a index, or 0 if no such key exists. \sa keyCount(), value(), valueToKey() */ const char *QMetaEnum::key(int index) const { if (!mobj) return 0; int count = mobj->d.data[handle + 2]; int data = mobj->d.data[handle + 3]; if (index >= 0 && index < count) return mobj->d.stringdata + mobj->d.data[data + 2*index]; return 0; } /*! Returns the value with the given \a index; or returns -1 if there is no such value. \sa keyCount(), key(), keyToValue() */ int QMetaEnum::value(int index) const { if (!mobj) return 0; int count = mobj->d.data[handle + 2]; int data = mobj->d.data[handle + 3]; if (index >= 0 && index < count) return mobj->d.data[data + 2*index + 1]; return -1; } /*! Returns true if this enumerator is used as a flag; otherwise returns false. When used as flags, enumerators can be combined using the OR operator. \sa keysToValue(), valueToKeys() */ bool QMetaEnum::isFlag() const { return mobj && mobj->d.data[handle + 1]; } /*! Returns the scope this enumerator was declared in. For example, the Qt::AlignmentFlag enumeration has \c Qt as the scope and \c AlignmentFlag as the name. \sa name() */ const char *QMetaEnum::scope() const { return mobj?mobj->d.stringdata : 0; } /*! Returns the integer value of the given enumeration \a key, or -1 if \a key is not defined. For flag types, use keysToValue(). \sa valueToKey(), isFlag(), keysToValue() */ int QMetaEnum::keyToValue(const char *key) const { if (!mobj || !key) return -1; uint scope = 0; const char *qualified_key = key; const char *s = key + qstrlen(key); while (s > key && *s != ':') --s; if (s > key && *(s-1)==':') { scope = s - key - 1; key += scope + 2; } int count = mobj->d.data[handle + 2]; int data = mobj->d.data[handle + 3]; for (int i = 0; i < count; ++i) if ((!scope || (qstrlen(mobj->d.stringdata) == scope && strncmp(qualified_key, mobj->d.stringdata, scope) == 0)) && strcmp(key, mobj->d.stringdata + mobj->d.data[data + 2*i]) == 0) return mobj->d.data[data + 2*i + 1]; return -1; } /*! Returns the string that is used as the name of the given enumeration \a value, or 0 if \a value is not defined. For flag types, use valueToKeys(). \sa isFlag(), valueToKeys() */ const char* QMetaEnum::valueToKey(int value) const { if (!mobj) return 0; int count = mobj->d.data[handle + 2]; int data = mobj->d.data[handle + 3]; for (int i = 0; i < count; ++i) if (value == (int)mobj->d.data[data + 2*i + 1]) return mobj->d.stringdata + mobj->d.data[data + 2*i]; return 0; } /*! Returns the value derived from combining together the values of the \a keys using the OR operator, or -1 if \a keys is not defined. Note that the strings in \a keys must be '|'-separated. \sa isFlag(), valueToKey(), valueToKeys() */ int QMetaEnum::keysToValue(const char *keys) const { if (!mobj) return -1; QStringList l = QString::fromLatin1(keys).split(QLatin1Char('|')); //#### TODO write proper code, do not use QStringList int value = 0; int count = mobj->d.data[handle + 2]; int data = mobj->d.data[handle + 3]; for (int li = 0; li < l.size(); ++li) { QString trimmed = l.at(li).trimmed(); QByteArray qualified_key = trimmed.toLatin1(); const char *key = qualified_key.constData(); uint scope = 0; const char *s = key + qstrlen(key); while (s > key && *s != ':') --s; if (s > key && *(s-1)==':') { scope = s - key - 1; key += scope + 2; } int i; for (i = count-1; i >= 0; --i) if ((!scope || (qstrlen(mobj->d.stringdata) == scope && strncmp(qualified_key.constData(), mobj->d.stringdata, scope) == 0)) && strcmp(key, mobj->d.stringdata + mobj->d.data[data + 2*i]) == 0) { value |= mobj->d.data[data + 2*i + 1]; break; } if (i < 0) value |= -1; } return value; } /*! Returns a byte array of '|'-separated keys that represents the given \a value. \sa isFlag(), valueToKey(), keysToValue() */ QByteArray QMetaEnum::valueToKeys(int value) const { QByteArray keys; if (!mobj) return keys; int count = mobj->d.data[handle + 2]; int data = mobj->d.data[handle + 3]; int v = value; for(int i = 0; i < count; i++) { int k = mobj->d.data[data + 2*i + 1]; if ((k != 0 && (v & k) == k ) || (k == value)) { v = v & ~k; if (!keys.isEmpty()) keys += '|'; keys += mobj->d.stringdata + mobj->d.data[data + 2*i]; } } return keys; } static QByteArray qualifiedName(const QMetaEnum &e) { return QByteArray(e.scope()) + "::" + e.name(); } /*! \class QMetaProperty \brief The QMetaProperty class provides meta-data about a property. \ingroup objectmodel Property meta-data is obtained from an object's meta-object. See QMetaObject::property() and QMetaObject::propertyCount() for details. \section1 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. \section1 Copying and Assignment QMetaProperty objects can be copied by value. However, each copy will refer to the same underlying property meta-data. \sa QMetaObject, QMetaEnum, QMetaMethod, {Qt's Property System} */ /*! \fn bool QMetaProperty::isValid() const Returns true if this property is valid (readable); otherwise returns false. \sa isReadable() */ /*! \fn const QMetaObject *QMetaProperty::enclosingMetaObject() const \internal */ /*! \internal */ QMetaProperty::QMetaProperty() : mobj(0), handle(0), idx(0) { } /*! Returns this property's name. \sa type(), typeName() */ const char *QMetaProperty::name() const { if (!mobj) return 0; int handle = priv(mobj->d.data)->propertyData + 3*idx; return mobj->d.stringdata + mobj->d.data[handle]; } /*! Returns the name of this property's type. \sa type(), name() */ const char *QMetaProperty::typeName() const { if (!mobj) return 0; int handle = priv(mobj->d.data)->propertyData + 3*idx; return mobj->d.stringdata + mobj->d.data[handle + 1]; } /*! Returns this property's type. The return value is one of the values of the QVariant::Type enumeration. \sa userType(), typeName(), name() */ QVariant::Type QMetaProperty::type() const { 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()); #endif return QVariant::UserType; } /*! \since 4.2 Returns this property's user type. The return value is one of the values that are registered with QMetaType, or 0 if the type is not registered. \sa type(), QMetaType, typeName() */ int QMetaProperty::userType() const { QVariant::Type tp = type(); if (tp != QVariant::UserType) return tp; if (isEnumType()) { int enumMetaTypeId = QMetaType::type(qualifiedName(menum)); return enumMetaTypeId; } return QMetaType::type(typeName()); } /*! \since 4.6 Returns this property's index. */ int QMetaProperty::propertyIndex() const { if (!mobj) return -1; return idx + mobj->propertyOffset(); } /*! 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. \sa isEnumType(), enumerator(), QMetaEnum::isFlag() */ bool QMetaProperty::isFlagType() const { return isEnumType() && menum.isFlag(); } /*! Returns true if the property's type is an enumeration value; otherwise returns false. \sa enumerator(), isFlagType() */ bool QMetaProperty::isEnumType() const { 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(); } /*! \internal Returns true if the property has a C++ setter function that follows Qt's standard "name" / "setName" pattern. Designer and uic query hasStdCppSet() in order to avoid expensive QObject::setProperty() calls. All properties in Qt [should] follow this pattern. */ bool QMetaProperty::hasStdCppSet() const { if (!mobj) return false; int handle = priv(mobj->d.data)->propertyData + 3*idx; int flags = mobj->d.data[handle + 2]; return (flags & StdCppSet); } /*! Returns the enumerator if this property's type is an enumerator type; otherwise the returned value is undefined. \sa isEnumType(), isFlagType() */ QMetaEnum QMetaProperty::enumerator() const { return menum; } /*! Reads the property's value from the given \a object. Returns the value if it was able to read it; otherwise returns an invalid variant. \sa write(), reset(), isReadable() */ QVariant QMetaProperty::read(const QObject *object) const { 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(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; } /*! Writes \a value as the property's value to the given \a object. Returns true if the write succeeded; otherwise returns false. \sa read(), reset(), isWritable() */ bool QMetaProperty::write(QObject *object, const QVariant &value) const { 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(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; } /*! Resets the property for the given \a object with a reset method. Returns true if the reset worked; otherwise returns false. Reset methods are optional; only a few properties support them. \sa read(), write() */ bool QMetaProperty::reset(QObject *object) const { if (!object || !mobj || !isResettable()) return false; void *argv[] = { 0 }; QMetaObject::metacall(object, QMetaObject::ResetProperty, idx + mobj->propertyOffset(), argv); return true; } /*! Returns true if this property can be reset to a default value; otherwise returns false. \sa reset() */ bool QMetaProperty::isResettable() const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Resettable; } /*! Returns true if this property is readable; otherwise returns false. \sa isWritable(), read(), isValid() */ bool QMetaProperty::isReadable() const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Readable; } /*! Returns true if this property has a corresponding change notify signal; otherwise returns false. \sa notifySignal() */ bool QMetaProperty::hasNotifySignal() const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Notify; } /*! \since 4.5 Returns the QMetaMethod instance of the property change notifying signal if one was specified, otherwise returns an invalid QMetaMethod. \sa hasNotifySignal() */ QMetaMethod QMetaProperty::notifySignal() const { int id = notifySignalIndex(); if (id != -1) return mobj->method(id); else return QMetaMethod(); } /*! \since 4.6 Returns the index of the property change notifying signal if one was specified, otherwise returns -1. \sa hasNotifySignal() */ int QMetaProperty::notifySignalIndex() const { 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; } } /*! Returns true if this property is writable; otherwise returns false. \sa isReadable(), write() */ bool QMetaProperty::isWritable() const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Writable; } /*! Returns true if this property is designable for the given \a object; otherwise returns false. If no \a object is given, the function returns false if the \c{Q_PROPERTY()}'s \c DESIGNABLE attribute is false; otherwise returns true (if the attribute is true or is a function or expression). \sa isScriptable(), isStored() */ bool QMetaProperty::isDesignable(const QObject *object) const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; bool b = flags & Designable; if (object) { void *argv[] = { &b }; QMetaObject::metacall(const_cast(object), QMetaObject::QueryPropertyDesignable, idx + mobj->propertyOffset(), argv); } return b; } /*! Returns true if the property is scriptable for the given \a object; otherwise returns false. If no \a object is given, the function returns false if the \c{Q_PROPERTY()}'s \c SCRIPTABLE attribute is false; otherwise returns true (if the attribute is true or is a function or expression). \sa isDesignable(), isStored() */ bool QMetaProperty::isScriptable(const QObject *object) const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; bool b = flags & Scriptable; if (object) { void *argv[] = { &b }; QMetaObject::metacall(const_cast(object), QMetaObject::QueryPropertyScriptable, idx + mobj->propertyOffset(), argv); } return b; } /*! Returns true if the property is stored for \a object; otherwise returns false. If no \a object is given, the function returns false if the \c{Q_PROPERTY()}'s \c STORED attribute is false; otherwise returns true (if the attribute is true or is a function or expression). \sa isDesignable(), isScriptable() */ bool QMetaProperty::isStored(const QObject *object) const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; bool b = flags & Stored; if (object) { void *argv[] = { &b }; QMetaObject::metacall(const_cast(object), QMetaObject::QueryPropertyStored, idx + mobj->propertyOffset(), argv); } return b; } /*! Returns true if this property is designated as the \c USER property, i.e., the one that the user can edit for \a object or that is significant in some other way. Otherwise it returns false. e.g., the \c text property is the \c USER editable property of a QLineEdit. If \a object is null, the function returns false if the \c {Q_PROPERTY()}'s \c USER attribute is false. Otherwise it returns true. \sa QMetaObject::userProperty(), isDesignable(), isScriptable() */ bool QMetaProperty::isUser(const QObject *object) const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; bool b = flags & User; if (object) { void *argv[] = { &b }; QMetaObject::metacall(const_cast(object), QMetaObject::QueryPropertyUser, idx + mobj->propertyOffset(), argv); } return b; } /*! \since 4.6 Returns true if the property is constant; otherwise returns false. A property is constant if the \c{Q_PROPERTY()}'s \c CONSTANT attribute is set. */ bool QMetaProperty::isConstant() const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Constant; } /*! \since 4.6 Returns true if the property is final; otherwise returns false. A property is final if the \c{Q_PROPERTY()}'s \c FINAL attribute is set. */ bool QMetaProperty::isFinal() const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; return flags & Final; } /*! \obsolete 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 \c{Q_PROPERTY()}'s \c EDITABLE attribute is false; otherwise returns true (if the attribute is true or is a function or expression). \sa isDesignable(), isScriptable(), isStored() */ bool QMetaProperty::isEditable(const QObject *object) const { if (!mobj) return false; int flags = mobj->d.data[handle + 2]; bool b = flags & Editable; if (object) { void *argv[] = { &b }; QMetaObject::metacall(const_cast(object), QMetaObject::QueryPropertyEditable, idx + mobj->propertyOffset(), argv); } return b; } /*! \class QMetaClassInfo \brief The QMetaClassInfo class provides additional information about a class. \ingroup objectmodel Class information items are simple \e{name}--\e{value} pairs that are specified using Q_CLASSINFO() in the source code. The information can be retrieved using name() and value(). For example: \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp 5 This mechanism is free for you to use in your Qt applications. Qt doesn't use it for any of its classes. \sa QMetaObject */ /*! \fn QMetaClassInfo::QMetaClassInfo() \internal */ /*! \fn const QMetaObject *QMetaClassInfo::enclosingMetaObject() const \internal */ /*! Returns the name of this item. \sa value() */ const char *QMetaClassInfo::name() const { if (!mobj) return 0; return mobj->d.stringdata + mobj->d.data[handle]; } /*! Returns the value of this item. \sa name() */ const char* QMetaClassInfo::value() const { if (!mobj) return 0; return mobj->d.stringdata + mobj->d.data[handle + 1]; } /*! \macro QGenericArgument Q_ARG(Type, const Type &value) \relates QMetaObject This macro takes a \a Type and a \a value of that type and returns a \l QGenericArgument object that can be passed to QMetaObject::invokeMethod(). \sa Q_RETURN_ARG() */ /*! \macro QGenericReturnArgument Q_RETURN_ARG(Type, Type &value) \relates QMetaObject This macro takes a \a Type and a non-const reference to a \a value of that type and returns a QGenericReturnArgument object that can be passed to QMetaObject::invokeMethod(). \sa Q_ARG() */ /*! \class QGenericArgument \brief The QGenericArgument class is an internal helper class for marshalling arguments. This class should never be used directly. Please use the \l Q_ARG() macro instead. \sa Q_ARG(), QMetaObject::invokeMethod(), QGenericReturnArgument */ /*! \fn QGenericArgument::QGenericArgument(const char *name, const void *data) Constructs a QGenericArgument object with the given \a name and \a data. */ /*! \fn QGenericArgument::data () const Returns the data set in the constructor. */ /*! \fn QGenericArgument::name () const Returns the name set in the constructor. */ /*! \class QGenericReturnArgument \brief The QGenericReturnArgument class is an internal helper class for marshalling arguments. This class should never be used directly. Please use the Q_RETURN_ARG() macro instead. \sa Q_RETURN_ARG(), QMetaObject::invokeMethod(), QGenericArgument */ /*! \fn QGenericReturnArgument::QGenericReturnArgument(const char *name, void *data) Constructs a QGenericReturnArgument object with the given \a name and \a data. */ /*! \internal If the local_method_index is a cloned method, return the index of the original. Example: if the index of "destroyed()" is passed, the index of "destroyed(QObject*)" is returned */ int QMetaObjectPrivate::originalClone(const QMetaObject *mobj, int local_method_index) { Q_ASSERT(local_method_index < get(mobj)->methodCount); int handle = get(mobj)->methodData + 5 * local_method_index; while (mobj->d.data[handle + 4] & MethodCloned) { Q_ASSERT(local_method_index > 0); handle -= 5; local_method_index--; } return local_method_index; } QT_END_NAMESPACE