ui rendering works now

src/Engine/UI/Elements/CMakeLists.txt

@@ -1,4 +1,6 @@
 target_sources(Engine
     PRIVATE
         Element.h
-        Element.cpp)
+        Element.cpp
+        Panel.h
+        Panel.cpp)

src/Engine/UI/Elements/Element.cpp

@@ -1,5 +1,6 @@
 #include "Element.h"
 #include "UI/System.h"
+#include "Graphics/Graphics.h"
 
 using namespace Seele;
 using namespace Seele::UI;

src/Engine/UI/Elements/Element.h

@@ -36,7 +36,6 @@ protected:
     PSystem system;
     PElement parent;
     Array<PElement> children;
-    friend class Layout;
     friend class RenderElement;
 };
 DEFINE_REF(Element)

src/Engine/UI/Elements/Panel.cpp

@@ -0,0 +1,15 @@
+#include "Panel.h"
+#include "UI/Layout.h"
+
+using namespace Seele;
+using namespace Seele::UI;
+
+Panel::Panel()
+{
+    
+}
+
+Panel::~Panel()
+{
+    
+}

src/Engine/UI/Elements/Panel.h

@@ -5,12 +5,16 @@ namespace Seele
 {
 namespace UI
 {
+DECLARE_REF(Layout)
 class Panel : Element
 {
 public:
     Panel();
     virtual ~Panel();
+private:
+    PLayout activeLayout;
 };
+
 DEFINE_REF(Panel);
 } // namespace UI
 } // namespace Seele