From 18c4672ba26b38c94a04027283fabfbed2c0ebeb Mon Sep 17 00:00:00 2001
From: Jared Boone <jboone@earfeast.com>
Date: Mon, 14 Dec 2015 10:52:08 -0800
Subject: [PATCH] Clean up navigation stack alloc/delete sequence.

---
 firmware/application/ui_navigation.cpp | 44 ++++++++++++--------------
 firmware/application/ui_navigation.hpp |  3 +-
 2 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/firmware/application/ui_navigation.cpp b/firmware/application/ui_navigation.cpp
index afa1bc73..3f6a0a38 100644
--- a/firmware/application/ui_navigation.cpp
+++ b/firmware/application/ui_navigation.cpp
@@ -49,43 +49,41 @@ NavigationView::NavigationView()
 }
 
 void NavigationView::push_view(View* new_view) {
-	// TODO: Trap nullptr?
-	// TODO: Trap push of object already on stack?
+	free_view();
+
 	view_stack.push_back(new_view);
-	set_view(new_view);
+
+	update_view();
 }
 
 void NavigationView::pop() {
 	// Can't pop last item from stack.
 	if( view_stack.size() > 1 ) {
-		const auto old_view = view_stack.back();
+		free_view();
+
+		delete view_stack.back();
 		view_stack.pop_back();
-		const auto new_view = view_stack.back();
-		set_view(new_view);
-		delete old_view;
+
+		update_view();
 	}
 }
 
+void NavigationView::free_view() {
+	remove_child(view());
+}
+
+void NavigationView::update_view() {
+	const auto new_view = view_stack.back();
+	add_child(new_view);
+	new_view->set_parent_rect({ {0, 0}, size() });
+	focus();
+	set_dirty();
+}
+
 Widget* NavigationView::view() const {
 	return children_.empty() ? nullptr : children_[0];
 }
 
-void NavigationView::set_view(Widget* const new_view) {
-	const auto old_view = view();
-	if( old_view ) {
-		remove_child(old_view);
-	}
-
-	// TODO: Allow new_view == nullptr?!
-	if( new_view ) {
-		add_child(new_view);
-		new_view->set_parent_rect({ {0, 0}, size() });
-		focus();
-	}
-
-	set_dirty();
-}
-
 void NavigationView::focus() {
 	if( view() ) {
 		view()->focus();
diff --git a/firmware/application/ui_navigation.hpp b/firmware/application/ui_navigation.hpp
index 0e12438e..4d4cd2ad 100644
--- a/firmware/application/ui_navigation.hpp
+++ b/firmware/application/ui_navigation.hpp
@@ -72,8 +72,9 @@ private:
 	std::vector<View*> view_stack;
 
 	Widget* view() const;
-	void set_view(Widget* const new_view);
 
+	void free_view();
+	void update_view();
 	void push_view(View* new_view);
 };