Use move_only_function and move implementation to cpp.

app/aspire/main.cpp

@@ -17,6 +17,9 @@ auto main() -> int
 	window->setWidth(defaultWidth);
 	window->setHeight(defaultHeight);
 	window->setTitle("Aspire");
+	window->setColor(sf::Color::Green);
+
+	auto root = std::make_unique<aspire::scene::Node>();
 
 	auto rect = std::make_unique<aspire::scene::Rectangle>();
 	rect->setPosition({80, 80});
@@ -27,7 +30,9 @@ auto main() -> int
 	subrect->setColor(sf::Color::Red);
 	subrect->setRotation(30);
 	rect->addChild(std::move(subrect));
-	window->setRootNode(std::move(rect));
+
+	root->addChild(std::move(rect));
+	window->setRootNode(std::move(root));
 
 	kernel.addService(std::move(window));
 

include/aspire/core/Object.h

@@ -58,25 +58,14 @@ namespace aspire::core
 		/// @return True if this object has been processed. Otherwise, false.
 		auto isStartup() -> bool;
 
-		template <typename T>
-		auto onChildAdded(T x)
-		{
-			return this->signalChildAdded.connect(std::forward<T>(x));
-		}
-
-		template <typename T>
-		auto onChildRemoved(T x)
-		{
-			return this->signalChildRemoved.connect(std::forward<T>(x));
-		}
+		auto onChildAdded(std::move_only_function<void(Object*)> x) -> sigslot::connection;
+		auto onChildRemoved(std::move_only_function<void(Object*)> x) -> sigslot::connection;
 
 	protected:
 		virtual auto onStartup() -> void;
+		auto kernel() -> Kernel&;
 
 	private:
-		sigslot::signal<Object*> signalChildAdded;
-		sigslot::signal<Object*> signalChildRemoved;
-
 		struct Impl;
 		Pimpl<Impl> pimpl;
 	};

src/core/Object.cpp

@@ -7,6 +7,10 @@ using aspire::core::Object;
 struct Object::Impl
 {
 	std::vector<std::unique_ptr<Object>> children;
+
+	sigslot::signal<Object*> childRemoved;
+	sigslot::signal<Object*> childAdded;
+
 	Object* parent{};
 	std::string name;
 	bool isStartup{false};
@@ -41,7 +45,7 @@ auto Object::addChild(std::unique_ptr<Object> x) -> void
 	x->pimpl->parent = this;
 	this->pimpl->children.emplace_back(std::move(x));
 
-	this->signalChildAdded(temp);
+	this->pimpl->childAdded(temp);
 
 	// Once the object has been started, we need to invoke any new objects that get added dynamically after the fact.
 	if(this->isStartup() && !temp->isStartup())
@@ -68,7 +72,7 @@ auto Object::remove() -> std::unique_ptr<Object>
 	this->pimpl->parent->pimpl->children.erase(beg, end);
 	node->pimpl->parent = nullptr;
 
-	this->signalChildRemoved(node.get());
+	this->pimpl->childRemoved(node.get());
 
 	return node;
 }
@@ -104,6 +108,16 @@ auto Object::isStartup() -> bool
 	return this->pimpl->isStartup;
 }
 
+auto Object::onChildAdded(std::move_only_function<void(Object*)> x) -> sigslot::connection
+{
+	return this->pimpl->childAdded.connect(std::move(x));
+}
+
+auto Object::onChildRemoved(std::move_only_function<void(Object*)> x) -> sigslot::connection
+{
+	return this->pimpl->childRemoved.connect(std::move(x));
+}
+
 auto Object::onStartup() -> void
 {
 }