JTEvent

Overview

Qt Event like, without Qt essential support.

Features

• Fast for coding, fast for performance
• Object method callback
• Strong type constraints
• Support for compilers as vs/g++/llvm/clang
• Automatic disconnect, no need to concern about disconnect

Usage

All you need

• Event<T>
• EventTarget has a Method which implement *void foo(T)
• connect EventTarget and Method to Event
• trigger the Event

Event<T>

Event<int> onChange;

EventTarget

class Number : public JT::EventTarget {
public:
    /* some code we don't care about */
    
    //this is the slot to event which we just made
    void onChangedSlot(int newVal)
    {
    	if (newVal == m_val) return;
        m_val = newVal;
    }
}

Connection

Event<int> onChange;
Number* number = new Number;
onChange.connect(number, EVENT_SLOT(Number::onChangedSlot, int));

Trigger the Event

//call the Event just like normal function
onChange(1);

Full sample

#include <iostream>
#include "JTEvent.h"

class Number : public JT::EventTarget {
public:
    Number() : m_val(0) {}
    ~Number() {}

    void setValue(int newVal)
    {
        if (newVal == m_val) return;

        m_val = newVal;
        onChange(m_val);
    }

    int getValue(void)
    {
        return m_val;
    }

    void onSliderChangedSlot(int newVal)
    {
        std::cout << "Number::onSliderChangedSlot: " << newVal << std::endl;
        setValue(newVal);
    }

    JT::Event<int> onChange;

private:
    int m_val;
};

class Slider : public Number {
public:
    Slider() {}
    ~Slider() {}

    void onNumberChangedSlot(int newVal)
    {
        std::cout << "Slider::onNumberChangedSlot: " << newVal << std::endl;
        setValue(newVal);
    }
};

int main() {
    Slider* slider = new Slider;
    Number* number = new Number;

    /* test connected events */
    slider->onChange.connect(number, EVENT_SLOT(Number::onSliderChangedSlot, int));
    number->onChange.connect(slider, EVENT_SLOT(Slider::onNumberChangedSlot, int));

    slider->setValue(10);
    std::cout << "slider value: " << slider->getValue() << std::endl;
    std::cout << "number value: " << number->getValue() << std::endl;

    number->setValue(20);
    std::cout << "slider value: " << slider->getValue() << std::endl;
    std::cout << "number value: " << number->getValue() << std::endl;

    /* automatic disconnect while EventTarget deleted */
    delete number;
    slider->setValue(10);

    delete slider;

    return 0;
}

Running Tests

$ cd test
$ make
$ output/test