Add loop posting utilities in ui::element

libs/ui/include/psemek/ui/element.hpp

@@ -51,6 +51,9 @@ namespace psemek::ui
 
 		virtual ~element() {}
 
+		virtual void post(std::function<void()> f);
+		virtual void post_reshape();
+
 	private:
 		element * parent_ = nullptr;
 		async::executor * loop_ = nullptr;

libs/ui/source/button.cpp

@@ -47,7 +47,7 @@ namespace psemek::ui
 			{
 				state_ = state_t::mousedown;
 				if (callback_)
-					root()->loop()->post(callback_);
+					post(callback_);
 				on_state_changed();
 				return true;
 			}

libs/ui/source/element.cpp

@@ -1,5 +1,7 @@
 #include <psemek/ui/element.hpp>
 
+#include <psemek/log/log.hpp>
+
 namespace psemek::ui
 {
 
@@ -34,4 +36,22 @@ namespace psemek::ui
 		return st;
 	}
 
+	void element::post(std::function<void()> f)
+	{
+		auto l = root()->loop();
+		if (l)
+			l->post(std::move(f));
+		else
+			log::warning() << "posting ui event while not attached to event loop";
+	}
+
+	void element::post_reshape()
+	{
+		auto weak_self = weak_from_this();
+		post([weak_self]{
+			if (auto self = weak_self.lock())
+				self->root()->reshape();
+		});
+	}
+
 }