From cfb830ca263defc307f9cfac74fb6771f6b7bfc6 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 17 Sep 2019 22:38:04 +0300
Subject: [PATCH] Implement next/previous navigation in Panel

The order is the one widgets were added in, which I think should produce
a sensible result in common scenarios.
---
 source/panel.cpp | 31 ++++++++++++++++++++++++++++++-
 source/panel.h   |  1 +
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/source/panel.cpp b/source/panel.cpp
index a9d581f..97e13a2 100644
--- a/source/panel.cpp
+++ b/source/panel.cpp
@@ -1,4 +1,4 @@
-#include <algorithm>
+#include <msp/core/algorithm.h>
 #include <msp/core/maputils.h>
 #include <msp/core/refptr.h>
 #include "button.h"
@@ -104,6 +104,28 @@ bool Panel::navigate(Navigation nav)
 			return true;
 		}
 	}
+	else if(nav==NAV_NEXT || nav==NAV_PREVIOUS)
+	{
+		vector<Widget *>::iterator i = find(nav_order, input_focus);
+
+		if(nav==NAV_NEXT)
+		{
+			if(i!=nav_order.end())
+				++i;
+			if(i==nav_order.end())
+				i = nav_order.begin();
+		}
+		else
+		{
+			if(i==nav_order.begin())
+				i = nav_order.end();
+			--i;
+		}
+
+		set_input_focus(*i);
+
+		return true;
+	}
 
 	return false;
 }
@@ -159,6 +181,9 @@ void Panel::on_geometry_change()
 
 void Panel::on_child_added(Widget &wdg)
 {
+	if(wdg.get_input_type()!=INPUT_NONE)
+		nav_order.push_back(&wdg);
+
 	if(layout)
 	{
 		layout->add_widget(wdg);
@@ -168,6 +193,10 @@ void Panel::on_child_added(Widget &wdg)
 
 void Panel::on_child_removed(Widget &wdg)
 {
+	vector<Widget *>::iterator i = std::remove(nav_order.begin(), nav_order.end(), &wdg);
+	if(i!=nav_order.end())
+		nav_order.erase(i, nav_order.end());
+
 	if(layout)
 	{
 		layout->remove_widget(wdg);
diff --git a/source/panel.h b/source/panel.h
index 8d67d14..756108a 100644
--- a/source/panel.h
+++ b/source/panel.h
@@ -58,6 +58,7 @@ private:
 	};
 
 protected:
+	std::vector<Widget *> nav_order;
 	Layout *layout;
 
 	Panel(const Panel &);
-- 
2.43.0