1 files changed, 86 insertions, 0 deletions
diff --git a/include/cru/ui/render/LayoutRenderObject.h b/include/cru/ui/render/LayoutRenderObject.h
new file mode 100644
index 00000000..42a3aa55
--- /dev/null
+++ b/include/cru/ui/render/LayoutRenderObject.h
@@ -0,0 +1,86 @@
+#pragma once
+#include "RenderObject.h"
+
+#include "cru/platform/graphics/util/Painter.h"
+
+namespace cru::ui::render {
+template <typename TChildLayoutData>
+class CRU_UI_API LayoutRenderObject : public RenderObject {
+ public:
+  using ChildLayoutData = TChildLayoutData;
+
+ protected:
+  LayoutRenderObject() : RenderObject(ChildMode::Multiple) {}
+
+ public:
+  CRU_DELETE_COPY(LayoutRenderObject)
+  CRU_DELETE_MOVE(LayoutRenderObject)
+
+  ~LayoutRenderObject() override = default;
+
+  const std::vector<ChildLayoutData>& GetChildLayoutDataList() const {
+    return this->child_layout_data_;
+  }
+
+  void SetChildLayoutData(Index position, ChildLayoutData data) {
+    Expects(position >= 0 &&
+            position < static_cast<Index>(this->child_layout_data_.size()));
+    this->child_layout_data_[position] = std::move(data);
+    this->InvalidateLayout();
+  }
+
+  const ChildLayoutData& GetChildLayoutData(Index position) const {
+    Expects(position >= 0 &&
+            position < static_cast<Index>(this->child_layout_data_.size()));
+    return this->child_layout_data_[position];
+  }
+
+  RenderObject* HitTest(const Point& point) override;
+
+ protected:
+  void OnAddChild(RenderObject* new_child, Index position) override;
+  void OnRemoveChild(RenderObject* removed_child, Index position) override;
+
+ private:
+  std::vector<ChildLayoutData> child_layout_data_{};
+};
+
+template <typename TChildLayoutData>
+RenderObject* LayoutRenderObject<TChildLayoutData>::HitTest(
+    const Point& point) {
+  const auto& children = GetChildren();
+  for (auto i = children.crbegin(); i != children.crend(); ++i) {
+    auto offset = (*i)->GetOffset();
+    Point p{point.x - offset.x, point.y - offset.y};
+    const auto result = (*i)->HitTest(p);
+    if (result != nullptr) {
+      return result;
+    }
+  }
+
+  const auto margin = GetMargin();
+  const auto size = GetSize();
+  return Rect{margin.left, margin.top,
+              std::max(size.width - margin.GetHorizontalTotal(), 0.0f),
+              std::max(size.height - margin.GetVerticalTotal(), 0.0f)}
+                 .IsPointInside(point)
+             ? this
+             : nullptr;
+}  // namespace cru::ui::render
+
+template <typename TChildLayoutData>
+void LayoutRenderObject<TChildLayoutData>::OnAddChild(RenderObject* new_child,
+                                                      const Index position) {
+  CRU_UNUSED(new_child)
+
+  child_layout_data_.emplace(child_layout_data_.cbegin() + position);
+}
+
+template <typename TChildLayoutData>
+void LayoutRenderObject<TChildLayoutData>::OnRemoveChild(
+    RenderObject* removed_child, const Index position) {
+  CRU_UNUSED(removed_child)
+
+  child_layout_data_.erase(child_layout_data_.cbegin() + position);
+}
+}  // namespace cru::ui::render