How to use the same C++ code for Android and iOS?

Question

Android with NDK has support to C/C++ code and iOS with Objective-C++ has support too, so how can I write applications with native C/C++ code shared between Android and iOS?

Answer 1

Approach described in the excellent answer above can be completely automated by Scapix Language Bridge which generates wrapper code on the fly directly from C++ headers. Here is an example:

Define your class in C++:

#include 

class contact : public scapix::bridge::object
{
public:
    std::string name();
    void send_message(const std::string& msg, std::shared_ptr from);
    void add_tags(const std::vector& tags);
    void add_friends(std::vector> friends);
};

And call it from Swift:

class ViewController: UIViewController {
    func send(friend: Contact) {
        let c = Contact()

        contact.sendMessage("Hello", friend)
        contact.addTags(["a","b","c"])
        contact.addFriends([friend])
    }
}

And from Java:

class View {
    private contact = new Contact;

    public void send(Contact friend) {
        contact.sendMessage("Hello", friend);
        contact.addTags({"a","b","c"});
        contact.addFriends({friend});
    }
}