...

9 files changed, 130 insertions, 23 deletions

diff --git a/include/cru/ui/render/BorderRenderObject.hpp b/include/cru/ui/render/BorderRenderObject.hpp
index c3031f59..45df89f9 100644
--- a/include/cru/ui/render/BorderRenderObject.hpp
+++ b/include/cru/ui/render/BorderRenderObject.hpp
@@ -67,9 +67,9 @@ class BorderRenderObject : public RenderObject {
   RenderObject* HitTest(const Point& point) override;
 
  protected:
-  void OnMeasureCore(const Size& available_size) override;
-  void OnLayoutCore(const Rect& rect) override;
-  Size OnMeasureContent(const Size& available_size) override;
+  Size OnMeasureCore(const MeasureRequirement& requirement) override;
+  void OnLayoutCore(const Size& size) override;
+  Size OnMeasureContent(const MeasureRequirement& requirement) override;
   void OnLayoutContent(const Rect& content_rect) override;
 
   void OnAfterLayout() override;
@@ -85,7 +85,7 @@ class BorderRenderObject : public RenderObject {
   bool is_border_enabled_ = false;
 
   std::shared_ptr<platform::graph::IBrush> border_brush_;
-  platform::Thickness border_thickness_;
+  Thickness border_thickness_;
   CornerRadius border_radius_;
 
   std::shared_ptr<platform::graph::IBrush> foreground_brush_;
diff --git a/include/cru/ui/render/CanvasRenderObject.hpp b/include/cru/ui/render/CanvasRenderObject.hpp
index ba50a985..402302cb 100644
--- a/include/cru/ui/render/CanvasRenderObject.hpp
+++ b/include/cru/ui/render/CanvasRenderObject.hpp
@@ -28,7 +28,7 @@ class CanvasRenderObject : public RenderObject {
   IEvent<CanvasPaintEventArgs>* PaintEvent() { return &paint_event_; }
 
  protected:
-  Size OnMeasureContent(const Size& available_size) override;
+  Size OnMeasureContent(const MeasureRequirement& requirement) override;
   void OnLayoutContent(const Rect& content_rect) override;
 
  private:
diff --git a/include/cru/ui/render/FlexLayoutRenderObject.hpp b/include/cru/ui/render/FlexLayoutRenderObject.hpp
index bc43141d..217ca6cb 100644
--- a/include/cru/ui/render/FlexLayoutRenderObject.hpp
+++ b/include/cru/ui/render/FlexLayoutRenderObject.hpp
@@ -31,7 +31,7 @@ class FlexLayoutRenderObject : public LayoutRenderObject<FlexChildLayoutData> {
   }
 
  protected:
-  Size OnMeasureContent(const Size& available_size) override;
+  Size OnMeasureContent(const MeasureRequirement& requirement) override;
   void OnLayoutContent(const Rect& content_rect) override;
 
  private:
diff --git a/include/cru/ui/render/MeasureRequirement.hpp b/include/cru/ui/render/MeasureRequirement.hpp
new file mode 100644
index 00000000..83de255d
--- /dev/null
+++ b/include/cru/ui/render/MeasureRequirement.hpp
@@ -0,0 +1,79 @@
+#pragma once
+#include "Base.hpp"
+
+#include <limits>
+
+namespace cru::ui::render {
+class MeasureLength {
+ public:
+  struct tag_infinate_t {};
+  constexpr static tag_infinate_t tag_infinate{};
+
+  constexpr MeasureLength() : MeasureLength(0) {}
+  constexpr MeasureLength(tag_infinate_t) : length_(-1) {}
+  constexpr MeasureLength(float length) : length_(length) {
+    Expects(length >= 0);
+  }
+
+  MeasureLength(const MeasureLength& other) = default;
+  MeasureLength& operator=(const MeasureLength& other) = default;
+  MeasureLength& operator=(float length) {
+    Expects(length >= 0);
+    length_ = length;
+    return *this;
+  }
+
+  ~MeasureLength() = default;
+
+  constexpr static MeasureLength Infinate() {
+    return MeasureLength{tag_infinate};
+  }
+
+  constexpr bool IsInfinate() const { return length_ < 0; }
+  constexpr float GetLength() const {
+    return length_ < 0 ? std::numeric_limits<float>::max() : length_;
+  }
+
+  constexpr bool operator==(MeasureLength other) const {
+    return (length_ < 0 && other.length_ < 0) || length_ == other.length_;
+  }
+
+  constexpr bool operator!=(MeasureLength other) const {
+    return !operator==(other);
+  }
+
+ private:
+  // -1 for infinate
+  float length_;
+};
+
+struct MeasureRequirement {
+  MeasureLength max_width;
+  MeasureLength max_height;
+
+  constexpr MeasureRequirement() = default;
+  constexpr MeasureRequirement(MeasureLength max_width,
+                               MeasureLength max_height)
+      : max_width(max_width), max_height(max_height) {}
+
+  constexpr MeasureRequirement(const Size& max_size)
+      : max_width(max_size.width), max_height(max_size.height) {}
+
+  constexpr bool Satisfy(const Size& size) const {
+    if (!max_width.IsInfinate() && max_width.GetLength() < size.width)
+      return false;
+    if (!max_height.IsInfinate() && max_height.GetLength() < size.height)
+      return false;
+    return true;
+  }
+
+  constexpr Size GetMaxSize() const {
+    return Size{max_width.GetLength(), max_height.GetLength()};
+  }
+
+  constexpr static MeasureRequirement Infinate() {
+    return MeasureRequirement{MeasureLength::Infinate(),
+                              MeasureLength::Infinate()};
+  }
+};
+}  // namespace cru::ui::render
diff --git a/include/cru/ui/render/RenderObject.hpp b/include/cru/ui/render/RenderObject.hpp
index 7cfa3883..9de2cc27 100644
--- a/include/cru/ui/render/RenderObject.hpp
+++ b/include/cru/ui/render/RenderObject.hpp
@@ -1,12 +1,22 @@
 #pragma once
 #include "Base.hpp"
 
+#include "MeasureRequirement.hpp"
 #include "cru/common/Event.hpp"
 
 namespace cru::ui::render {
+
 // Render object will not destroy its children when destroyed. Control must
 // manage lifecycle of its render objects. Since control will destroy its
 // children when destroyed, render objects will be destroyed along with it.
+//
+// To write a custom RenderObject, override following methods:
+// public:
+//  void Draw(platform::graph::IPainter* painter) override;
+//  RenderObject* HitTest(const Point& point) override;
+// protected:
+//  Size OnMeasureContent(const MeasureRequirement& requirement) override;
+//  void OnLayoutContent(const Rect& content_rect) override;
 class RenderObject : public Object {
   friend WindowRenderObject;
 
@@ -41,12 +51,12 @@ class RenderObject : public Object {
   void AddChild(RenderObject* render_object, Index position);
   void RemoveChild(Index position);
 
+  // Offset from parent's lefttop to lefttop of this render object. Margin is
+  // accounted for.
   Point GetOffset() const { return offset_; }
-  void SetOffset(const Point& offset) { offset_ = offset; }
+  Size GetSize() const { return size_; }
   Point GetTotalOffset() const;
   Point FromRootToContent(const Point& point) const;
-  Size GetSize() const { return size_; }
-  void SetSize(const Size& size) { size_ = size; }
 
   Thickness GetMargin() const { return margin_; }
   void SetMargin(const Thickness& margin) { margin_ = margin; }
@@ -54,16 +64,16 @@ class RenderObject : public Object {
   Thickness GetPadding() const { return padding_; }
   void SetPadding(const Thickness& padding) { padding_ = padding; }
 
-  Size GetPreferredSize() const { return preferred_size_; }
-  void SetPreferredSize(const Size& preferred_size) {
-    preferred_size_ = preferred_size;
-  }
+  Size GetMeasuredSize() const { return measured_size_; }
 
-  void Measure(const Size& available_size);
+  void Measure(const MeasureRequirement& requirement);
+  // Size of rect must not be negative.
   void Layout(const Rect& rect);
 
   virtual void Draw(platform::graph::IPainter* painter) = 0;
 
+  // Param point must be relative the lefttop of render object including margin.
+  // Add offset before pass point to children.
   virtual RenderObject* HitTest(const Point& point) = 0;
 
  public:
@@ -82,9 +92,23 @@ class RenderObject : public Object {
   // default is to invalidate both layout and paint
   virtual void OnRemoveChild(RenderObject* removed_child, Index position);
 
-  virtual void OnMeasureCore(const Size& available_size);
-  virtual void OnLayoutCore(const Rect& rect);
-  virtual Size OnMeasureContent(const Size& available_size) = 0;
+  // Size measure including margin and padding. Please reduce margin and padding
+  // or other custom things and pass the result content measure requirement to
+  // OnMeasureContent.
+  // Return value must not be negative and not bigger than requirement.
+  virtual Size OnMeasureCore(const MeasureRequirement& requirement);
+
+  // Size including margin and padding. Please reduce margin and padding or
+  // other custom things and pass the result content rect to OnLayoutContent.
+  // Parameter size are never negative.
+  virtual void OnLayoutCore(const Size& size);
+
+  // Do not consider margin or padding in this method because they are already
+  // considered in OnMeasureCore. Returned size should never be bigger than
+  // requirement.
+  virtual Size OnMeasureContent(const MeasureRequirement& requirement) = 0;
+
+  // Lefttop of content_rect should be added when calculated children's offset.
   virtual void OnLayoutContent(const Rect& content_rect) = 0;
 
   virtual void OnAfterLayout();
@@ -113,6 +137,6 @@ class RenderObject : public Object {
   Thickness margin_{};
   Thickness padding_{};
 
-  Size preferred_size_{};
+  Size measured_size_{};
 };
 }  // namespace cru::ui::render
diff --git a/include/cru/ui/render/ScrollRenderObject.hpp b/include/cru/ui/render/ScrollRenderObject.hpp
index dcf6dae6..924b8ca6 100644
--- a/include/cru/ui/render/ScrollRenderObject.hpp
+++ b/include/cru/ui/render/ScrollRenderObject.hpp
@@ -21,8 +21,12 @@ class ScrollRenderObject : public RenderObject {
   void SetScrollOffset(const Point& offset);
 
  protected:
-  void OnAddChild(RenderObject* new_child, Index position) override;
-  void OnRemoveChild(RenderObject* removed_child, Index position) override;
+  // Logic:
+  // If available size is bigger than child's preferred size, then child's
+  // preferred size is taken.
+  // If not, all available size is taken while forming a scroll area.
+  Size OnMeasureContent(const MeasureRequirement& requirement) override;
+  void OnLayoutContent(const Rect& content_rect) override;
 
  private:
   Point scroll_offset_;
diff --git a/include/cru/ui/render/StackLayoutRenderObject.hpp b/include/cru/ui/render/StackLayoutRenderObject.hpp
index a5bf9335..2320e1ca 100644
--- a/include/cru/ui/render/StackLayoutRenderObject.hpp
+++ b/include/cru/ui/render/StackLayoutRenderObject.hpp
@@ -11,7 +11,7 @@ class StackLayoutRenderObject
   ~StackLayoutRenderObject() = default;
 
  protected:
-  Size OnMeasureContent(const Size& available_size) override;
+  Size OnMeasureContent(const MeasureRequirement& requirement) override;
   void OnLayoutContent(const Rect& content_rect) override;
 };
 }  // namespace cru::ui::render
diff --git a/include/cru/ui/render/TextRenderObject.hpp b/include/cru/ui/render/TextRenderObject.hpp
index 7a81ba51..96bb5997 100644
--- a/include/cru/ui/render/TextRenderObject.hpp
+++ b/include/cru/ui/render/TextRenderObject.hpp
@@ -64,7 +64,7 @@ class TextRenderObject : public RenderObject {
   RenderObject* HitTest(const Point& point) override;
 
  protected:
-  Size OnMeasureContent(const Size& available_size) override;
+  Size OnMeasureContent(const MeasureRequirement& requirement) override;
   void OnLayoutContent(const Rect& content_rect) override;
 
   void OnAfterLayout() override;
diff --git a/include/cru/ui/render/WindowRenderObject.hpp b/include/cru/ui/render/WindowRenderObject.hpp
index 00bce29b..d993dc58 100644
--- a/include/cru/ui/render/WindowRenderObject.hpp
+++ b/include/cru/ui/render/WindowRenderObject.hpp
@@ -16,7 +16,7 @@ class WindowRenderObject : public RenderObject {
   RenderObject* HitTest(const Point& point) override;
 
  protected:
-  Size OnMeasureContent(const Size& available_size) override;
+  Size OnMeasureContent(const MeasureRequirement& requirement) override;
   void OnLayoutContent(const Rect& content_rect) override;
 
  private: