From ae62c05fe97d341c4f219656cdce7aadf321991b Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Thu, 1 Sep 2016 10:46:57 +0300
Subject: [PATCH] Move navigation logic from Container to Panel

A number of widgets inherit from Container because they have internal
sub-widgets, but have their own navigation logic.  Panel is the user-
visible generic container.
---
 source/container.cpp | 64 +++-----------------------------------------
 source/panel.cpp     | 64 ++++++++++++++++++++++++++++++++++++++++++++
 source/panel.h       |  4 +++
 3 files changed, 72 insertions(+), 60 deletions(-)

diff --git a/source/container.cpp b/source/container.cpp
index b50bc29..c38509f 100644
--- a/source/container.cpp
+++ b/source/container.cpp
@@ -304,66 +304,10 @@ void Container::focus_out()
 
 bool Container::navigate(Navigation nav)
 {
-	if(input_focus && input_focus->navigate(nav))
-		return true;
-
-	if(nav==NAV_UP || nav==NAV_DOWN || nav==NAV_LEFT || nav==NAV_RIGHT)
-	{
-		int x = geom.w/2;
-		int y = geom.h/2;
-		if(input_focus)
-		{
-			const Geometry &fgeom = input_focus->get_geometry();
-			x = fgeom.x+fgeom.w/2;
-			y = fgeom.y+fgeom.h/2;
-		}
-		else if(nav==NAV_UP)
-			y = 0;
-		else if(nav==NAV_DOWN)
-			y = geom.h;
-		else if(nav==NAV_RIGHT)
-			x = 0;
-		else if(nav==NAV_LEFT)
-			x = geom.w;
-
-		Widget *sibling = 0;
-		int best_score = 0;
-		for(list<Child *>::const_iterator i=children.begin(); i!=children.end(); ++i)
-		{
-			if((*i)->widget==input_focus || !(*i)->widget->is_focusable())
-				continue;
-
-			const Geometry &cgeom = (*i)->widget->get_geometry();
-			int dx = cgeom.x+cgeom.w/2-x;
-			int dy = cgeom.y+cgeom.h/2-y;
-
-			int score = -1;
-			if(nav==NAV_UP && dy>0)
-				score = dy+abs(dx)*4;
-			else if(nav==NAV_DOWN && dy<0)
-				score = -dy+abs(dx)*4;
-			else if(nav==NAV_RIGHT && dx>0)
-				score = dx+abs(dy)*4;
-			else if(nav==NAV_LEFT && dx<0)
-				score = -dx+abs(dy)*4;
-
-			if(score>0 && (!sibling || score<best_score))
-			{
-				sibling = (*i)->widget;
-				best_score = score;
-			}
-		}
-
-		if(sibling)
-		{
-			set_input_focus(sibling);
-			if(Container *container = dynamic_cast<Container *>(sibling))
-				container->navigate(nav);
-			return true;
-		}
-	}
-
-	return false;
+	if(input_focus)
+		return input_focus->navigate(nav);
+	else
+		return false;
 }
 
 void Container::on_reparent()
diff --git a/source/panel.cpp b/source/panel.cpp
index c17fe4b..7e34c59 100644
--- a/source/panel.cpp
+++ b/source/panel.cpp
@@ -59,6 +59,70 @@ void Panel::render_special(const Part &part, GL::Renderer &renderer) const
 	}
 }
 
+bool Panel::navigate(Navigation nav)
+{
+	if(Container::navigate(nav))
+		return true;
+
+	if(nav==NAV_UP || nav==NAV_DOWN || nav==NAV_LEFT || nav==NAV_RIGHT)
+	{
+		int x = geom.w/2;
+		int y = geom.h/2;
+		if(input_focus)
+		{
+			const Geometry &fgeom = input_focus->get_geometry();
+			x = fgeom.x+fgeom.w/2;
+			y = fgeom.y+fgeom.h/2;
+		}
+		else if(nav==NAV_UP)
+			y = 0;
+		else if(nav==NAV_DOWN)
+			y = geom.h;
+		else if(nav==NAV_RIGHT)
+			x = 0;
+		else if(nav==NAV_LEFT)
+			x = geom.w;
+
+		Widget *sibling = 0;
+		int best_score = 0;
+		for(list<Child *>::const_iterator i=children.begin(); i!=children.end(); ++i)
+		{
+			if((*i)->widget==input_focus || !(*i)->widget->is_focusable())
+				continue;
+
+			const Geometry &cgeom = (*i)->widget->get_geometry();
+			int dx = cgeom.x+cgeom.w/2-x;
+			int dy = cgeom.y+cgeom.h/2-y;
+
+			int score = -1;
+			if(nav==NAV_UP && dy>0)
+				score = dy+abs(dx)*4;
+			else if(nav==NAV_DOWN && dy<0)
+				score = -dy+abs(dx)*4;
+			else if(nav==NAV_RIGHT && dx>0)
+				score = dx+abs(dy)*4;
+			else if(nav==NAV_LEFT && dx<0)
+				score = -dx+abs(dy)*4;
+
+			if(score>0 && (!sibling || score<best_score))
+			{
+				sibling = (*i)->widget;
+				best_score = score;
+			}
+		}
+
+		if(sibling)
+		{
+			set_input_focus(sibling);
+			if(Panel *panel = dynamic_cast<Panel *>(sibling))
+				panel->navigate(nav);
+			return true;
+		}
+	}
+
+	return false;
+}
+
 void Panel::on_geometry_change()
 {
 	if(layout)
diff --git a/source/panel.h b/source/panel.h
index e0eed01..ebe765d 100644
--- a/source/panel.h
+++ b/source/panel.h
@@ -71,6 +71,10 @@ protected:
 	virtual void autosize_special(const Part &, Geometry &) const;
 	virtual void render_special(const Part &, GL::Renderer &) const;
 
+public:
+	virtual bool navigate(Navigation);
+
+protected:
 	virtual void on_geometry_change();
 	virtual void on_child_added(Widget &);
 	virtual void on_child_removed(Widget &);
-- 
2.43.0