C++ Constructors and static members

Question

I was trying something out and i don't know what is going on with the code. I have a class which has a static member and the default constructor and an overloaded one.

class Remote
{
public:
    static std::vector<Remote*> channels;

    static void interrupt() {
        for (Remote* r : channels) {
            r->ProcessInterrupt();
        };
    }

    void ProcessInterrupt() {
        std::cout << "ProcessInterrupt called.";
    };

    Remote(const int a) {
        std::cout << "Remote(const int a) called.\n";
        channels.push_back(this);
    }
    Remote() {
        Remote(1);
        std::cout << "Remote() called.\n";
    }
    ~Remote() {
        std::vector<Remote *>::iterator ch = std::find(channels.begin(), channels.end(), this);
        if (ch != channels.end()) {
            channels.erase(ch);
        };
    }
};

In main.cpp i declare two instances of the class Remote. What i now notice is that if i instantiate them with the default constructor the pointers are not added to the vector. Then i tried using the overloaded constructor and it does add it to the vector.

Remote r1 = Remote();
Remote r2 = Remote(1);
std::cout << Remote::channels.size() << "\n";
Remote::interrupt();

I would expect that since i'm calling the overloaded constructor it would still add the pointer to the vector. This, however, is clearly not happening.

Could anyone explain what is happening?

Kind regards,

Bob

Answer 1

The constructor

Remote() {
    Remote(1);
    std::cout << "Remote() called.\n";
}

Doesn't add anything to the channels vector. Remote(1) in this context , is not a delegating constructor.

Try this instead:

Remote() : Remote(1) {
    std::cout << "Remote() called.\n";
}

See an example here: https://ideone.com/ahauPV