C++: creating an event repeatedly called by timer - c++

Question

I wanted to redo a Conway's Game of Life thing I did in Java, but this time use ncurses and C++. Obviously I need a timed event so I can run out the simulation at a rate which it can be viewed. Turns out it is a hell of a lot harder to make a timed event in C++ than it is in Java. I am not as experienced in C++ than I am in Java. I have already looked around online, and what I found led me to the code I have below. Upon executing it produces no result in the terminal. What exactly am I doing wrong?
main.cpp:
#include <iostream>
#include <functional>
#include <chrono>
#include <future>
#include <cstdio>
using namespace std;
class callBackTimer //no idea how this works, got it from Stack Overflow thread
{
public:
callBackTimer()
:_execute(false)
{}
void start(int interval, std::function<void(void)> func)
{
_execute = true;
std::thread([=]()
{
while (_execute)
{
func();
std::this_thread::sleep_for(
std::chrono::milliseconds(interval));
}
}).detach();
}
void stop()
{
_execute = false;
}
private:
bool _execute;
};
void timerExec()
{
cout << "SNAFU" << endl;
}
int main(int argc, const char * argv[])
{
callBackTimer timer; //declare the timer
std::function<void(void)> exec = timerExec; //declare a pointer to timerExec
timer.start(25, std::bind(exec)); //start the timer
return 0;
}

Answer 1

You need to wait for the thread to finish what it is doing, which is usually accomplished by calling join(). So maybe something like this:
#include <iostream>
#include <functional>
#include <chrono>
#include <future>
#include <cstdio>
using namespace std;
class callBackTimer //no idea how this works, got it from Stack Overflow thread
{
public:
callBackTimer()
:_execute(false)
{}
void setup(int interval, std::function<void(void)> func)
{
_execute = true;
thread = std::thread([=]()
{
// while (_execute)
for (int steps = 0; steps < 100; ++steps)
{
func();
std::this_thread::sleep_for(std::chrono::milliseconds(interval));
}
});
}
void stop()
{
_execute = false;
}
void run()
{
thread.join();
}
private:
bool _execute;
std::thread thread;
};
void timerExec()
{
cout << "SNAFU" << endl;
}
int main(int argc, const char * argv[])
{
callBackTimer timer; //declare the timer
std::function<void(void)> exec = timerExec; //declare a pointer to timerExec
timer.setup(25, std::bind(exec)); //start the timer
timer.run();
return 0;
}
Calling detach() is OK, but you have to make main() wait for the thread manually. You also need a condition to break out of the while loop, otherwise it will go on forever. Hope that helps!