fix some struct

example/layers/ui_layer/ui_layer.cpp

@@ -2,7 +2,7 @@
 
 #include "utils.hpp"
 
-namespace sandbox
+namespace example
 {
   void ui_layer::on_attach() 
   {
@@ -13,11 +13,17 @@ namespace sandbox
 
   void ui_layer::render()
   {
-    // VE::WinPos(m_pos);
-    // VE::WinSize(m_pos);
+    ImGui::SetNextWindowPos(m_pos);
+    ImGui::SetNextWindowSize(m_size);
 
-    VE::Begin("name", m_pos, m_size, m_win_flags);
-    VE::End();
+    if (!ImGui::Begin(VE_NAME("Test signal"), nullptr, m_win_flags)) ImGui::End();
+
+    VE_PUSH_FONT(REGULAR, 20);
+    if (ImGui::Button("Test signal", ImVec2(128, 130))) 
+      VE::EMIT(test_event::TEST_EVEN, std::string("test event message"));
+    VE_POP_FONT();
+
+    ImGui::End();
   }
 
   void ui_layer::on_event(VE::event e)