1 files changed, 47 insertions, 0 deletions
diff --git a/include/cru/ui/model/IListChangeNotify.h b/include/cru/ui/model/IListChangeNotify.h
new file mode 100644
index 00000000..a9fcd65b
--- /dev/null
+++ b/include/cru/ui/model/IListChangeNotify.h
@@ -0,0 +1,47 @@
+#pragma once
+#include "../Base.h"
+#include "cru/common/Base.h"
+#include "cru/common/Event.h"
+
+namespace cru::ui::model {
+enum ListChangeType {
+  kItemAdd,
+  kItemRemove,
+  kItemSet,
+  kItemMove,
+  kClear,
+};
+
+struct CRU_UI_API ListChange {
+  ListChangeType type;
+  union {
+    Index position;
+  };
+  union {
+    Index count;
+    Index new_position;
+  };
+
+  constexpr static ListChange ItemAdd(Index index, Index count = 1) {
+    return {ListChangeType::kItemAdd, index, count};
+  }
+
+  constexpr static ListChange ItemRemove(Index index, Index count = 1) {
+    return {ListChangeType::kItemRemove, index, count};
+  }
+
+  constexpr static ListChange ItemSet(Index index, Index count = 1) {
+    return {ListChangeType::kItemSet, index, count};
+  }
+
+  constexpr static ListChange ItemMove(Index position, Index new_position) {
+    return {ListChangeType::kItemMove, position, new_position};
+  }
+
+  constexpr static ListChange Clear() { return {ListChangeType::kClear}; }
+};
+
+struct CRU_UI_API IListChangeNotify : virtual Interface {
+  virtual IEvent<ListChange>* ListChangeEvent() = 0;
+};
+}  // namespace cru::ui::model