[C++] 信号

前言

信号与槽是QT的一个概念，原版C++里并没有

使用

先声明一些类
Receiver负责接收信号，Emitter2则是负责发送

class Receiver : public ntl::Reflectible
{
public:void received(int num){std::cout << "received:" << num << std::endl;}
};class Emitter2 : public ntl::Signalable
{
public:Emitter2(){m_signals.insert(ntl::Signalable::SignalMap::value_type("signal",ntl::Signal(1)));}public:void emit_signal(){emit("signal", 123);}
};

接着连接信号
说明一下信号的名称、接收对象与方法

emitter2.connect("signal", "receiver", &receiver, &Receiver::received);

最后发送信号

emitter2.emit_signal();

没错的话应该输出以下字符

received:123

说明Receiver成功接收到了Emitter2发出的信号

代码

此物需要借助上篇文章的力量
并位于github之中，尔等可观赏其细节

Slot

Slot需要与对象绑定
用void*说明对象的位置
NonStaticMethod如其名，是一个用于调用的非静态方法

	/// @brief 槽class NTL_ALIGN Slot : public BasicObject{public:using SelfType = Slot;using ParentType = BasicObject;protected:/// @brief 槽的对象void *m_object = nullptr;/// @brief 方法NonStaticMethod m_method;public:Slot() = default;explicit Slot(void *object, const NonStaticMethod &method);explicit Slot(const SelfType &from) = default;~Slot() = default;public:SelfType &operator=(const SelfType &from) = default;public:void *get_object() const;const NonStaticMethod &get_method() const;public:template <typename... ArgsType>void received(ArgsType &&...args) const;};

Signal

Signal可以连接多个Slot，并允许删改

	/// @brief 信号class NTL_ALIGN Signal : public BasicObject{public:using SelfType = Signal;using ParentType = BasicObject;/// @brief 槽容器using SlotContainer = std::map<String, Slot>;protected:/// @brief 槽SlotContainer m_slots;/// @brief 参数总数SizeT m_args_count = 0;public:Signal() = default;explicit Signal(SizeT args_count);explicit Signal(const SelfType &from) = default;~Signal() = default;public:SelfType &operator=(const SelfType &from) = default;public:const SlotContainer &get_slots() const;SizeT get_args_count() const;bool has_slot(const String &name) const;public:template <typename MethodType>void connect(const String &name, void *object, MethodType method);void connect(const String &name, const Slot &slot);void disconnect(const String &name);template <typename... ArgsType>void emit(ArgsType &&...args) const;};

Signalable

Signalable是一个可以发送/接收信号的对象，继承自Reflectible

	/// @brief 可发送/接收信号的对象class NTL_ALIGN Signalable : public Reflectible{public:using SelfType = Signalable;using ParentType = Reflectible;/// @brief 信号列表using SignalMap = std::map<String, Signal>;protected:/// @brief 信号列表SignalMap m_signals;public:Signalable() = default;explicit Signalable(const SelfType &from) = default;~Signalable() = default;public:SelfType &operator=(const SelfType &from) = default;public:const SignalMap &get_signals() const;bool has_signal(const String &signal) const;public:template <typename MethodType>void connect(const String &signal, const String &name, void *object, MethodType method);void connect(const String &signal, const String &name, const Slot &slot);void disconnect(const String &signal, const String &name);template <typename... ArgsType>void emit(const String &signal, ArgsType &&...args) const;public:static OutOfRangeException unable_to_find_signal(const String &signal, const String &where);};