How to get body_entered callback in Area2D inheriting class in gdextension c++?

Godot Version

v4.2.1 stable


I have a c++ class called “Projectile” which inherits from Area2D. I would like my callback function on_body_entered to fire whenever a body enters the area of “Projectile”. Currently I am using get_overlapping_bodies() in my process function, which works fine (also with collision layer/mask), but I wanted to try and set it up with a callback because that seems like the intended way to handle collisions.

I see in the editor that Area2D has a signal called “body_entered(body: Node2D)” but I have no clue how to link that to my callback function. This is what the relevant parts of my class look like:

class Projectile : public Area2D {
    GDCLASS(Projectile, Area2D)

    static void _bind_methods() {
        // Attempt 3
        ClassDB::bind_method(D_METHOD("body_entered"), &Projectile::on_body_entered);

        // Attempt 4
        ClassDB::bind_method(D_METHOD("body_entered", "body"), &Projectile::on_body_entered);

    Projectile() {
         // Attempt 1
         connect("body_entered", Callable(this, "on_body_entered"));

         // Attempt 2
         this->connect("body_entered", Callable(this, "on_body_entered"));

    void on_body_entered(Node2D *body) {
        UtilityFunctions::print("Entered Body");

I cannot get my callback to fire on hitting objects, while get_overlapping_bodies() does work on them. Printing does work, I use it in this class and all over. What am I doing wrong? Am I being a dumbdumb?

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