Done.

1 files changed, 58 insertions, 4 deletions

diff --git a/src/ui/controls/frame_layout.cpp b/src/ui/controls/frame_layout.cpp
index 32d25edc..d68bc338 100644
--- a/src/ui/controls/frame_layout.cpp
+++ b/src/ui/controls/frame_layout.cpp
@@ -2,10 +2,7 @@
 
 namespace cru::ui::controls
 {
-    FrameLayout::FrameLayout() : Control(true)
-    {
-
-    }
+    FrameLayout::FrameLayout() = default;
 
     FrameLayout::~FrameLayout() = default;
 
@@ -13,4 +10,61 @@ namespace cru::ui::controls
     {
         return control_type;
     }
+
+    Size FrameLayout::OnMeasureContent(const Size& available_size, const AdditionalMeasureInfo& additional_info)
+    {
+        auto max_child_size = Size::Zero();
+        for (auto control: GetChildren())
+        {
+            control->Measure(available_size, additional_info);
+            const auto&& size = control->GetDesiredSize();
+            if (max_child_size.width < size.width)
+                max_child_size.width = size.width;
+            if (max_child_size.height < size.height)
+                max_child_size.height = size.height;
+        }
+
+        // coerce size fro stretch.
+        for (auto control: GetChildren())
+        {
+            auto size = control->GetDesiredSize();
+            const auto layout_params = control->GetLayoutParams();
+            if (layout_params->width.mode == MeasureMode::Stretch)
+                size.width = max_child_size.width;
+            if (layout_params->height.mode == MeasureMode::Stretch)
+                size.height = max_child_size.height;
+            control->SetDesiredSize(size);
+        }
+
+        return max_child_size;
+    }
+
+    void FrameLayout::OnLayoutContent(const Rect& rect, const AdditionalLayoutInfo& additional_info)
+    {
+        for (auto control: GetChildren())
+        {
+            const auto layout_params = control->GetLayoutParams();
+            const auto size = control->GetDesiredSize();
+
+            auto&& calculate_anchor = [](const float anchor, const Alignment alignment, const float layout_length, const float control_length) -> float
+            {
+                switch (alignment)
+                {
+                case Alignment::Center:
+                    return anchor + (layout_length - control_length) / 2;
+                case Alignment::Start:
+                    return anchor;
+                case Alignment::End:
+                    return anchor + layout_length - control_length;
+                default:
+                    UnreachableCode();
+                }
+            };
+
+            control->Layout(Rect(Point(
+                calculate_anchor(rect.left, layout_params->width.alignment, rect.width, size.width),
+                calculate_anchor(rect.top, layout_params->height.alignment, rect.height, size.height)
+            ), size), additional_info);
+        }
+    }
 }