Event Manager

Single-header C++ Event System.

Aim
Future
Requirements
API
Installation

Aim

Easy to use external API
- Simple, intuitive syntax
- No binding or passing in lambdas required
Events are simple PODS
- No inheritance of a base Event class
- No explicit registering of events
Efficient operation
- Suitable for real-time applications

Future

Delayed event queues
- Fired events can be pushed to a queue for deferred execution
Asynchronous events

Requirements

C++17

API

Registering Function Callbacks

#include "EventManager.h"

const int key_w = 87;

struct KeyPressEvent
{
    int key_code;
}

void on_key_press(KeyPressEvent* event)
{
    // ...
}

int main()
{
    EventManager::listen<KeyPressEvent>(&on_key_press);
    EventManager::fire<KeyPressEvent>(key_w);
}

Registering Member Callbacks

#include "EventManager.h"

const int key_w = 87;

struct KeyPressEvent
{
    int key_code;
}

class InputHandler
{
public:
    InputHandler()
    {
        EventManager::listen<KeyPressEvent>(this, &InputHandler::on_key_press);
    }
private:
    void on_key_press(KeyPressEvent* event)
    {
         // ...
    }
}

int main()
{
    InputHandler input_handler;
    EventManager::fire<KeyPressEvent>(key_w);
}

Unregister Callbacks

A ListenerHandle is returned to the user upon registering an event callback, and each callback function is uniquely associated with its given handle.

#include "EventManager.h"

const int key_w = 87;

struct KeyPressEvent
{
    int key_code;
}

void on_key_press(KeyPressEvent* event)
{
    // ...
}

int main()
{
    ListenerHandle handle = EventManager::listen<KeyPressEvent>(&on_key_press);
    EventManager::remove_listener(handle);
}

Installation

Event Manager is a single-header library so no build is required. You can either clone or directly download the repository and place EventManager.h in your include folder.

From here it is as simple as #include "EventManager.h" and you're ready to go.

Kainev/EventManager