Develop basic functions of ScrollControl.

1 files changed, 79 insertions, 8 deletions

diff --git a/src/ui/controls/scroll_control.hpp b/src/ui/controls/scroll_control.hpp
index c39b18f4..faf192ad 100644
--- a/src/ui/controls/scroll_control.hpp
+++ b/src/ui/controls/scroll_control.hpp
@@ -1,17 +1,34 @@
 #pragma once
 
+#include <optional>
+#include <initializer_list>
+
 #include "ui/control.hpp"
 
 namespace cru::ui::controls
 {
     // Done: OnMeasureContent
     // Done: OnLayoutContent
-    // TODO: HitTest
-    // TODO: Draw
-    // TODO: ScrollBar
+    // Done: HitTest(no need)
+    // Done: Draw(no need)
+    // Done: API
+    // Done: ScrollBar
     // TODO: MouseEvent
     class ScrollControl : public Control
     {
+    private:
+        struct ScrollBarInfo
+        {
+            Rect border = Rect();
+            Rect bar = Rect();
+        };
+
+        enum class Orientation
+        {
+            Horizontal,
+            Vertical
+        };
+
     public:
         enum class ScrollBarVisibility
         {
@@ -20,6 +37,16 @@ namespace cru::ui::controls
             Always
         };
 
+        static ScrollControl* Create(const std::initializer_list<Control*>& children = std::initializer_list<Control*>{})
+        {
+            const auto control = new ScrollControl(true);
+            for (auto child : children)
+                control->AddChild(child);
+            return control;
+        }
+
+        static constexpr auto control_type = L"ScrollControl";
+
     protected:
         explicit ScrollControl(bool container);
     public:
@@ -29,6 +56,7 @@ namespace cru::ui::controls
         ScrollControl& operator=(ScrollControl&& other) = delete;
         ~ScrollControl() override;
 
+        StringView GetControlType() const override final;
 
         bool IsHorizontalScrollEnabled() const
         {
@@ -45,14 +73,20 @@ namespace cru::ui::controls
         void SetVerticalScrollEnabled(bool enable);
 
 
-        ScrollBarVisibility GetHorizontalScrollBarVisibility() const;
+        ScrollBarVisibility GetHorizontalScrollBarVisibility() const
+        {
+            return horizontal_scroll_bar_visibility_;
+        }
+
         void SetHorizontalScrollBarVisibility(ScrollBarVisibility visibility);
-        ScrollBarVisibility GetVerticalScrollBarVisibility() const;
-        void SetVerticalScrollBarVisibility(ScrollBarVisibility visibility);
 
-        Control* HitTest(const Point& point) override final;
+        ScrollBarVisibility GetVerticalScrollBarVisibility() const
+        {
+            return vertical_scroll_bar_visibility_;
+        }
+
+        void SetVerticalScrollBarVisibility(ScrollBarVisibility visibility);
 
-    protected:
         float GetViewWidth() const
         {
             return view_width_;
@@ -63,12 +97,40 @@ namespace cru::ui::controls
             return view_height_;
         }
 
+        float GetScrollOffsetX() const
+        {
+            return offset_x_;
+        }
+
+        float GetScrollOffsetY() const
+        {
+            return offset_y_;
+        }
+
+        // nullopt for not set. value is auto-coerced.
+        void SetScrollOffset(std::optional<float> x, std::optional<float> y);
+
+    protected:
         void SetViewWidth(float length);
         void SetViewHeight(float length);
 
         Size OnMeasureContent(const Size& available_size) override final;
         void OnLayoutContent(const Rect& rect) override final;
 
+        void AfterLayoutSelf() override;
+
+        void OnDrawForeground(ID2D1DeviceContext* device_context) override;
+
+        void OnMouseDownCore(events::MouseButtonEventArgs& args) override final;
+        void OnMouseMoveCore(events::MouseEventArgs& args) override final;
+        void OnMouseUpCore(events::MouseButtonEventArgs& args) override final;
+
+    private:
+        void CoerceAndSetOffsets(float offset_x, float offset_y, bool update_children = true);
+        void UpdateScrollBarVisibility();
+        void UpdateScrollBarBorderInfo();
+        void UpdateScrollBarBarInfo();
+
     private:
         bool horizontal_scroll_enabled_ = true;
         bool vertical_scroll_enabled_ = true;
@@ -76,10 +138,19 @@ namespace cru::ui::controls
         ScrollBarVisibility horizontal_scroll_bar_visibility_ = ScrollBarVisibility::Auto;
         ScrollBarVisibility vertical_scroll_bar_visibility_ = ScrollBarVisibility::Auto;
 
+        bool is_horizontal_scroll_bar_visible_ = false;
+        bool is_vertical_scroll_bar_visible_ = false;
+
         float offset_x_ = 0.0f;
         float offset_y_ = 0.0f;
 
         float view_width_ = 0.0f;
         float view_height_ = 0.0f;
+
+        ScrollBarInfo horizontal_bar_info_;
+        ScrollBarInfo vertical_bar_info_;
+
+        std::optional<Orientation> is_pressing_scroll_bar_ = std::nullopt;
+        float pressing_delta_ = 0.0f;
     };
 }