Qt 的 PointerToMemberFunction 在哪里定义的?
Where is Qt’s PointerToMemberFunction defined?
在 中,我能够适应 QObject
方法
QMetaObject::Connection
QObject::connect(const QObject * sender,
const char * signal,
const QObject * receiver,
const char * method,
Qt::ConnectionType type = Qt::AutoConnection)
变成接受 QSharedPointer
而不是 QObject*
作为第一个参数的变体:
template<class T> QMetaObject::Connection
connect_from_pointer(const QSharedPointer<T> &sender,
const char *signal,
const QObject *receiver,
const char *method,
Qt::ConnectionType type = Qt::AutoConnection)
我想对采用函数指针的版本做同样的事情,
QMetaObject::Connection
QObject::connect(const QObject * sender,
PointerToMemberFunction signal,
const QObject * receiver,
PointerToMemberFunction method,
Qt::ConnectionType type = Qt::AutoConnection)
但是我不知道PointerToMemberFunction
是什么,也不知道它是在哪里定义的!这是什么类型?
它只是 "sugar" 文档,您可以在 qobject.h
(Qt 源代码)中找到真正的定义:
static QMetaObject::Connection connect(const QObject *sender, const char *signal,
const QObject *receiver, const char *member, Qt::ConnectionType = Qt::AutoConnection);
static QMetaObject::Connection connect(const QObject *sender, const QMetaMethod &signal,
const QObject *receiver, const QMetaMethod &method,
Qt::ConnectionType type = Qt::AutoConnection);
inline QMetaObject::Connection connect(const QObject *sender, const char *signal,
const char *member, Qt::ConnectionType type = Qt::AutoConnection) const;
#ifdef Q_QDOC
static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method, Qt::ConnectionType type = Qt::AutoConnection);
static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, Functor functor);
static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, const QObject *context, Functor functor, Qt::ConnectionType type = Qt::AutoConnection);
#else
//Connect a signal to a pointer to qobject member function
template <typename Func1, typename Func2>
static inline QMetaObject::Connection connect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal,
const typename QtPrivate::FunctionPointer<Func2>::Object *receiver, Func2 slot,
Qt::ConnectionType type = Qt::AutoConnection)
{
typedef QtPrivate::FunctionPointer<Func1> SignalType;
typedef QtPrivate::FunctionPointer<Func2> SlotType;
Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<typename SignalType::Object>::Value,
"No Q_OBJECT in the class with the signal");
//compilation error if the arguments does not match.
Q_STATIC_ASSERT_X(int(SignalType::ArgumentCount) >= int(SlotType::ArgumentCount),
"The slot requires more arguments than the signal provides.");
Q_STATIC_ASSERT_X((QtPrivate::CheckCompatibleArguments<typename SignalType::Arguments, typename SlotType::Arguments>::value),
"Signal and slot arguments are not compatible.");
Q_STATIC_ASSERT_X((QtPrivate::AreArgumentsCompatible<typename SlotType::ReturnType, typename SignalType::ReturnType>::value),
"Return type of the slot is not compatible with the return type of the signal.");
const int *types = 0;
if (type == Qt::QueuedConnection || type == Qt::BlockingQueuedConnection)
types = QtPrivate::ConnectionTypes<typename SignalType::Arguments>::types();
return connectImpl(sender, reinterpret_cast<void **>(&signal),
receiver, reinterpret_cast<void **>(&slot),
new QtPrivate::QSlotObject<Func2, typename QtPrivate::List_Left<typename SignalType::Arguments, SlotType::ArgumentCount>::Value,
typename SignalType::ReturnType>(slot),
type, types, &SignalType::Object::staticMetaObject);
}
在 QObject
方法
QMetaObject::Connection
QObject::connect(const QObject * sender,
const char * signal,
const QObject * receiver,
const char * method,
Qt::ConnectionType type = Qt::AutoConnection)
变成接受 QSharedPointer
而不是 QObject*
作为第一个参数的变体:
template<class T> QMetaObject::Connection
connect_from_pointer(const QSharedPointer<T> &sender,
const char *signal,
const QObject *receiver,
const char *method,
Qt::ConnectionType type = Qt::AutoConnection)
我想对采用函数指针的版本做同样的事情,
QMetaObject::Connection
QObject::connect(const QObject * sender,
PointerToMemberFunction signal,
const QObject * receiver,
PointerToMemberFunction method,
Qt::ConnectionType type = Qt::AutoConnection)
但是我不知道PointerToMemberFunction
是什么,也不知道它是在哪里定义的!这是什么类型?
它只是 "sugar" 文档,您可以在 qobject.h
(Qt 源代码)中找到真正的定义:
static QMetaObject::Connection connect(const QObject *sender, const char *signal,
const QObject *receiver, const char *member, Qt::ConnectionType = Qt::AutoConnection);
static QMetaObject::Connection connect(const QObject *sender, const QMetaMethod &signal,
const QObject *receiver, const QMetaMethod &method,
Qt::ConnectionType type = Qt::AutoConnection);
inline QMetaObject::Connection connect(const QObject *sender, const char *signal,
const char *member, Qt::ConnectionType type = Qt::AutoConnection) const;
#ifdef Q_QDOC
static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method, Qt::ConnectionType type = Qt::AutoConnection);
static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, Functor functor);
static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, const QObject *context, Functor functor, Qt::ConnectionType type = Qt::AutoConnection);
#else
//Connect a signal to a pointer to qobject member function
template <typename Func1, typename Func2>
static inline QMetaObject::Connection connect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal,
const typename QtPrivate::FunctionPointer<Func2>::Object *receiver, Func2 slot,
Qt::ConnectionType type = Qt::AutoConnection)
{
typedef QtPrivate::FunctionPointer<Func1> SignalType;
typedef QtPrivate::FunctionPointer<Func2> SlotType;
Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<typename SignalType::Object>::Value,
"No Q_OBJECT in the class with the signal");
//compilation error if the arguments does not match.
Q_STATIC_ASSERT_X(int(SignalType::ArgumentCount) >= int(SlotType::ArgumentCount),
"The slot requires more arguments than the signal provides.");
Q_STATIC_ASSERT_X((QtPrivate::CheckCompatibleArguments<typename SignalType::Arguments, typename SlotType::Arguments>::value),
"Signal and slot arguments are not compatible.");
Q_STATIC_ASSERT_X((QtPrivate::AreArgumentsCompatible<typename SlotType::ReturnType, typename SignalType::ReturnType>::value),
"Return type of the slot is not compatible with the return type of the signal.");
const int *types = 0;
if (type == Qt::QueuedConnection || type == Qt::BlockingQueuedConnection)
types = QtPrivate::ConnectionTypes<typename SignalType::Arguments>::types();
return connectImpl(sender, reinterpret_cast<void **>(&signal),
receiver, reinterpret_cast<void **>(&slot),
new QtPrivate::QSlotObject<Func2, typename QtPrivate::List_Left<typename SignalType::Arguments, SlotType::ArgumentCount>::Value,
typename SignalType::ReturnType>(slot),
type, types, &SignalType::Object::staticMetaObject);
}