Attempt implement menu (unresolved symbol error)

Menu.cpp

@@ -0,0 +1,50 @@
+#include <GL\freeglut.h>
+#include "Menu.h"
+
+Menu::Menu()
+{
+	cursor = Cursor::getInstance();
+}
+
+
+Menu::~Menu()
+{
+}
+
+void Menu::draw(void)
+{
+	//Switch view to Ortho
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+	glOrtho(0, 1000, 1000, 0, -10, 10);
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+
+	glDisable(GL_LIGHTING);
+	glDisable(GL_DEPTH_TEST);
+	glDisable(GL_TEXTURE_2D);
+
+
+	for (MenuElement* e : elements)
+	{
+		e->draw();
+	}
+
+	cursor->draw();
+
+	glEnable(GL_LIGHTING);
+	glEnable(GL_DEPTH_TEST);
+}
+
+void Menu::update()
+{
+	for (MenuElement* e : elements)
+	{
+		e->update(cursor->mousePosition.x, cursor->mousePosition.y);
+	}
+}
+
+void Menu::AddMenuElement(MenuElement * e)
+{
+	elements.push_back(e);
+}