From e630316a059244cf1e8ac139f52a6799eef835ce Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Thu, 10 Mar 2022 12:21:17 +0300
Subject: [PATCH] Add ui::single_container for wrapper elements

---
 .../include/psemek/ui/event_interceptor.hpp   | 11 ++--------
 libs/ui/include/psemek/ui/frame.hpp           | 11 ++--------
 libs/ui/include/psemek/ui/scroller.hpp        | 11 ++--------
 .../ui/include/psemek/ui/single_container.hpp | 21 +++++++++++++++++++
 libs/ui/source/event_interceptor.cpp          | 12 -----------
 libs/ui/source/frame.cpp                      | 12 -----------
 libs/ui/source/scroller.cpp                   | 12 -----------
 libs/ui/source/single_container.cpp           | 18 ++++++++++++++++
 8 files changed, 45 insertions(+), 63 deletions(-)
 create mode 100644 libs/ui/include/psemek/ui/single_container.hpp
 create mode 100644 libs/ui/source/single_container.cpp

diff --git a/libs/ui/include/psemek/ui/event_interceptor.hpp b/libs/ui/include/psemek/ui/event_interceptor.hpp
index 00972803..d027a2bc 100644
--- a/libs/ui/include/psemek/ui/event_interceptor.hpp
+++ b/libs/ui/include/psemek/ui/event_interceptor.hpp
@@ -1,6 +1,6 @@
 #pragma once
 
-#include <psemek/ui/element.hpp>
+#include <psemek/ui/single_container.hpp>
 
 #include <functional>
 
@@ -8,12 +8,8 @@ namespace psemek::ui
 {
 
 	struct event_interceptor
-		: element
+		: single_container
 	{
-		children_range children() const override { return children_; }
-
-		virtual std::shared_ptr<element> set_child(std::shared_ptr<element> c);
-
 		geom::box<float, 2> size_constraints() const override;
 
 		struct shape const & shape() const override;
@@ -32,9 +28,6 @@ namespace psemek::ui
 		void draw(painter &) const override {}
 
 	private:
-		std::shared_ptr<element> child_;
-		element * children_[1]{nullptr};
-
 		bool mouseover_ = false;
 
 		std::function<bool(mouse_move const &)> mouse_move_callback_;
diff --git a/libs/ui/include/psemek/ui/frame.hpp b/libs/ui/include/psemek/ui/frame.hpp
index 0012b55a..938d12a6 100644
--- a/libs/ui/include/psemek/ui/frame.hpp
+++ b/libs/ui/include/psemek/ui/frame.hpp
@@ -1,17 +1,13 @@
 #pragma once
 
-#include <psemek/ui/element.hpp>
+#include <psemek/ui/single_container.hpp>
 
 namespace psemek::ui
 {
 
 	struct frame
-		: element
+		: single_container
 	{
-		children_range children() const override { return children_; }
-
-		virtual std::shared_ptr<element> set_child(std::shared_ptr<element> c);
-
 		virtual void set_min_size(std::optional<geom::vector<float, 2>> const & size);
 		virtual void set_max_size(std::optional<geom::vector<float, 2>> const & size);
 		virtual void set_fixed_size(geom::vector<float, 2> const & size);
@@ -24,9 +20,6 @@ namespace psemek::ui
 	private:
 		std::optional<geom::vector<float, 2>> min_size_;
 		std::optional<geom::vector<float, 2>> max_size_;
-
-		std::shared_ptr<element> child_;
-		element * children_[1]{nullptr};
 	};
 
 }
diff --git a/libs/ui/include/psemek/ui/scroller.hpp b/libs/ui/include/psemek/ui/scroller.hpp
index debcc3bb..6192ede7 100644
--- a/libs/ui/include/psemek/ui/scroller.hpp
+++ b/libs/ui/include/psemek/ui/scroller.hpp
@@ -1,18 +1,14 @@
 #pragma once
 
-#include <psemek/ui/element.hpp>
+#include <psemek/ui/single_container.hpp>
 #include <psemek/ui/box_shape.hpp>
 
 namespace psemek::ui
 {
 
 	struct scroller
-		: element
+		: single_container
 	{
-		children_range children() const override { return children_; }
-
-		virtual std::shared_ptr<element> set_child(std::shared_ptr<element> c);
-
 		enum class direction
 		{
 			horizontal,
@@ -77,9 +73,6 @@ namespace psemek::ui
 		geom::vector<float, 2> shift_{0.f, 0.f};
 		geom::vector<float, 2> shift_tgt_{0.f, 0.f};
 
-		std::shared_ptr<element> child_;
-		element * children_[1]{nullptr};
-
 		void clamp_shift();
 	};
 
diff --git a/libs/ui/include/psemek/ui/single_container.hpp b/libs/ui/include/psemek/ui/single_container.hpp
new file mode 100644
index 00000000..62720603
--- /dev/null
+++ b/libs/ui/include/psemek/ui/single_container.hpp
@@ -0,0 +1,21 @@
+#pragma once
+
+#include <psemek/ui/element.hpp>
+
+namespace psemek::ui
+{
+
+	struct single_container
+		: element
+	{
+		children_range children() const override { return children_; }
+
+		virtual std::shared_ptr<element> set_child(std::shared_ptr<element> c);
+		virtual std::shared_ptr<element> child() { return child_; }
+
+	protected:
+		std::shared_ptr<element> child_;
+		element * children_[1]{nullptr};
+	};
+
+}
diff --git a/libs/ui/source/event_interceptor.cpp b/libs/ui/source/event_interceptor.cpp
index 1f36b2e9..9a171375 100644
--- a/libs/ui/source/event_interceptor.cpp
+++ b/libs/ui/source/event_interceptor.cpp
@@ -4,18 +4,6 @@
 namespace psemek::ui
 {
 
-	std::shared_ptr<element> event_interceptor::set_child(std::shared_ptr<element> c)
-	{
-		auto old = std::move(child_);
-		if (old) old->set_parent(nullptr);
-
-		child_ = std::move(c);
-		if (child_) child_->set_parent(this);
-		children_[0] = child_.get();
-
-		return old;
-	}
-
 	geom::box<float, 2> event_interceptor::size_constraints() const
 	{
 		if (child_)
diff --git a/libs/ui/source/frame.cpp b/libs/ui/source/frame.cpp
index cfe56a98..3b05cd99 100644
--- a/libs/ui/source/frame.cpp
+++ b/libs/ui/source/frame.cpp
@@ -3,18 +3,6 @@
 namespace psemek::ui
 {
 
-	std::shared_ptr<element> frame::set_child(std::shared_ptr<element> c)
-	{
-		auto old = std::move(child_);
-		if (old) old->set_parent(nullptr);
-
-		child_ = std::move(c);
-		if (child_) child_->set_parent(this);
-		children_[0] = child_.get();
-
-		return old;
-	}
-
 	void frame::set_min_size(std::optional<geom::vector<float, 2>> const & size)
 	{
 		min_size_ = size;
diff --git a/libs/ui/source/scroller.cpp b/libs/ui/source/scroller.cpp
index 6487d4b4..443eb46b 100644
--- a/libs/ui/source/scroller.cpp
+++ b/libs/ui/source/scroller.cpp
@@ -5,18 +5,6 @@
 namespace psemek::ui
 {
 
-	std::shared_ptr<element> scroller::set_child(std::shared_ptr<element> c)
-	{
-		auto old = std::move(child_);
-		if (old) old->set_parent(nullptr);
-
-		child_ = std::move(c);
-		if (child_) child_->set_parent(this);
-		children_[0] = child_.get();
-
-		return old;
-	}
-
 	void scroller::set_preferred_direction(direction d)
 	{
 		preferred_direction_ = d;
diff --git a/libs/ui/source/single_container.cpp b/libs/ui/source/single_container.cpp
new file mode 100644
index 00000000..8184a6df
--- /dev/null
+++ b/libs/ui/source/single_container.cpp
@@ -0,0 +1,18 @@
+#include <psemek/ui/single_container.hpp>
+
+namespace psemek::ui
+{
+
+	std::shared_ptr<element> single_container::set_child(std::shared_ptr<element> c)
+	{
+		auto old = std::move(child_);
+		if (old) old->set_parent(nullptr);
+
+		child_ = std::move(c);
+		if (child_) child_->set_parent(this);
+		children_[0] = child_.get();
+
+		return old;
+	}
+
+}