cpp_launchpad/compile/code/observable.h

89 lines
2.0 KiB
C++

#ifndef CODE_OBSERVABLE
#define CODE_OBSERVABLE
#include "code/return.h"
#include <vector>
template<class V> class observer_t {
public:
virtual void on_change(
V* value_p
) = 0;
};
template<class V> class observable_t {
public:
enum class error_t {
none,
unknown,
not_observing
};
struct configuration_t {
V* value_m;
};
observable_t(
configuration_t* configuration_p
) {
configuration_m = configuration_p;
}
void_t<error_t> observe(
observer_t<V>* observer_p
) {
observer_p->on_change(configuration_m->value_m);
observers_m.push_back(observer_p);
}
void_t<error_t> unobserve(
observer_t<V>* observer_p
) {
observable_t::error_t error_l = observable_t::error_t::not_observing;
for (int i = 0; i < observers_m.size(); i++) {
if (observers_m[i] == observer_p) {
observers_m.erase(i);
error_l = observable_t::error_t::none;
break;
}
}
void_t<observable_t::error_t> void_l;
void_l.error_m = error_l;
return void_l;
}
V* get_value() {
return value_m;
}
void_t<error_t> change(
V* value_p
) {
configuration_m->value_m = value_p;
for (int i = 0; i < observers_m.size(); i++) {
observer_m = observers_m[i];
observer_m->on_change(configuration_m->value_m);
}
void_t<observable_t::error_t> void_l;
void_l.error_m = observable_t::error_t::none;
return void_l;
}
private:
std::vector<observer_t<V>*> observers_m;
configuration_t* configuration_m;
};
template <class V> class observable_factory_t : public observable_t<V> {
public:
return_t<observable_t::error_t, observable_t<V> *> create(
observable_t::configuration_t configuration_p
) {
observable_t<V>* observable_l = new observable_t<V>(
configuration_p
);
return_t<observable_t::error_t, observable_t*> return_l;
return_l.error_m = observable_t::error_t::none;
return_l.value_m = observable_l;
return return_l;
}
void_t<observable_t::error_t> dispose(
observable_t<V>* observable_p
) {
delete observable_p;
void_t<observable_t::error_t> void_l;
void_l.error_m = observable_t::error_t::none;
return void_l;
}
};
#endif