Added state event.

src/dawn/state/StateProperty.hpp

@@ -4,15 +4,23 @@
 // https://opensource.org/licenses/MIT
 
 #pragma once
-#include "StateOwner.hpp"
+#include "assert/assert.hpp"
 
 namespace Dawn {
+  class StateOwner;
+
   template<class V>
   class StateProperty {
     private:
       StateOwner *owner;
       V value;
       
+      /**
+       * Method that is invoked every time that the value of this state property
+       * is updated.
+       * 
+       * @param val Value that is to be used for this property.
+       */
       void setInternal(V val) {
         if(val == this->value) return;// TODO: can I omit this? kinda bad tbh.
         assertNotNull(this->owner);
@@ -44,6 +52,9 @@ namespace Dawn {
         return this->value;
       }
 
+      /**
+       * Destructor for StateProperty.
+       */
       ~StateProperty() {
         this->owner->_statePropertyDestroyed(this);
       }