Hi
How to connect method with more arguments (pointers) to signal using e.g.
boost::bind?
The code below works, but if I eliminate Data_type class from desing, and try
to work directly on _two_ pointers I have a problem with connection methods
to signal slots.
Could anyone tell me how to do that?
Best regards.
#include
#include
#include <iostream>
#include <utility>
// some class
class Test {
public:
explicit Test(int x) : x_ (x) {}
int const x() const { return x_; }
operator int() { return x_; }
private:
int x_;
};
// class wrap references
class Data_type {
public:
Data_type(double & d, Test & t) : d_ (d), t_ (t) {}
double & d() const { return d_; }
Test & t() const { return t_; }
private:
double & d_;
Test & t_;
};
// class react on signals
class some_class {
public:
bool some_function(Data_type & dt) {
bool test = (dt.d() > 3.14);
std::cout << std::boolalpha << "Check " << dt.d()
<< " > 3.14 " << test << " and " << dt.t().x() << '\n';
return test;
}
bool another_function(Data_type & dt) {
bool test = (dt.d() > 3.14);
std::cout << std::boolalpha << "Check " << dt.d()
<< " > 3.14 " << test << " and " << dt.t().x() << '\n';
return test;
}
};
// signal source
class Caller {
public:
Caller() : sig0(), sig1() {}
~Caller(){}
typedef boost::signal signal_type;
typedef signal_type::slot_type slot_type;
signal_type sig0;
signal_type sig1;
void emit (double & d, Test & t) {
// conversion from 2 parameters to 1
Data_type tmp (d, t);
sig0 (tmp);
sig1 (tmp);
}
boost::signals::connection connect_to_sig0 (slot_type const & s) {
return sig0.connect (s);
}
boost::signals::connection connect_to_sig1 (slot_type const & s) {
return sig1.connect (s);
}
};
int main() {
using std::cout;
using namespace boost;
some_class sc;
Caller c;
// if I will eliminate Data_type class
// and change methods that they could take 2 arguments
// then bind can not meet requirements of slot_type
c.connect_to_sig0 (bind (&some_class::some_function, &sc, _1));
c.connect_to_sig1 (bind (&some_class::another_function, &sc, _1));
Test * t = new Test (4);
double * d = new double (3.14);
c.emit (*d, *t);
}
--
|\/\/| Seweryn Habdank-Wojewódzki
\/\/
