https://github.com/wqking/eventpp

eventpp is an open source C++ event library that provides tools that allow your application components to communicate with each other by dispatching events and listening to them. With eventpp you can implement signal/slot mechanism, or observer pattern, very easily.

Facts and features

• Powerful
  • Supports both synchronous event dispatching and asynchronous event queue.
  • Configurable and extensible with policies and mixins.
  • Supports event filter via mixins.
• Robust
  • Supports nested event. During handling an event a listener can safely dispatch event, append/prepend/insert/remove other listeners.
  • Thread safety. Supports multiple threading.
  • Exception safety. Most operations guarantee strong exception safety.
  • Well tested. Backed by unit tests.
• Fast
  • The EventQueue can process 10M events in 1 second (10K events per millisecond).
  • The CallbackList can invoke 100M callbacks in 1 second (100K callbacks per millisecond).
  • The CallbackList can add/remove 5M callbacks in 1 second (5K callbacks per millisecond).
• Flexible and easy to use
  • The listeners and events can be any type, no need to inherit from any base class.
  • Header only, no source file, no need to build. No dependencies on other libraries.
  • Requires C++ 11 (tested with MSVC 2017, MSVC 2015, MinGW (Msys) gcc 7.2, and Ubuntu gcc 5.4).
  • Written in portable and standard C++, no hacks or quirks.

License

Apache License, Version 2.0

Version 0.1.0

eventpp is currently usable and near stable.

Quick start

Namespace

eventpp

Using CallbackList

#include "eventpp/callbacklist.h"
eventpp::CallbackList<void (const std::string &, const bool)> callbackList;
callbackList.append([](const std::string & s, const bool b) {
	std::cout << std::boolalpha << "Got callback 1, s is " << s << " b is " << b << std::endl;
});
callbackList.append([](std::string s, int b) {
	std::cout << std::boolalpha << "Got callback 2, s is " << s << " b is " << b << std::endl;
});
callbackList("Hello world", true);

Using EventDispatcher

#include "eventpp/eventdispatcher.h"
eventpp::EventDispatcher<int, void ()> dispatcher;
dispatcher.appendListener(3, []() {
	std::cout << "Got event 3." << std::endl;
});
dispatcher.appendListener(5, []() {
	std::cout << "Got event 5." << std::endl;
});
dispatcher.appendListener(5, []() {
	std::cout << "Got another event 5." << std::endl;
});
// dispatch event 3
dispatcher.dispatch(3);
// dispatch event 5
dispatcher.dispatch(5);

Using EventQueue

eventpp::EventQueue<int, void (const std::string &, const bool)> queue;

dispatcher.appendListener(3, [](const std::string s, bool b) {
	std::cout << std::boolalpha << "Got event 3, s is " << s << " b is " << b << std::endl;
});
dispatcher.appendListener(5, [](const std::string s, bool b) {
	std::cout << std::boolalpha << "Got event 5, s is " << s << " b is " << b << std::endl;
});

// The listeners are not triggered during enqueue.
queue.enqueue(3, "Hello", true);
queue.enqueue(5, "World", false);

// Process the event queue, dispatch all queued events.
queue.process();

Please check Github for the source code and documentations.

https://github.com/wqking/eventpp