Move nav back button outside of ReceiverView.

firmware/application/ui_navigation.cpp

@@ -40,14 +40,29 @@ namespace ui {
 
 SystemStatusView::SystemStatusView() {
 	add_children({ {
+		&button_back,
 		&portapack,
 		&sd_card_status_view,
 	} });
 	sd_card_status_view.set_parent_rect({ 28 * 8, 0 * 16,  2 * 8, 1 * 16 });
+
+	button_back.on_select = [this](Button&){
+		if( this->on_back ) {
+			this->on_back();
+		}
+	};
+}
+
+void SystemStatusView::set_back_visible(bool new_value) {
+	button_back.hidden(!new_value);
 }
 
 /* Navigation ************************************************************/
 
+bool NavigationView::is_top() const {
+	return view_stack.size() == 1;
+}
+
 View* NavigationView::push_view(std::unique_ptr<View> new_view) {
 	free_view();
 
@@ -80,6 +95,10 @@ void NavigationView::update_view() {
 	new_view->set_parent_rect({ {0, 0}, size() });
 	focus();
 	set_dirty();
+
+	if( on_view_changed ) {
+		on_view_changed();
+	}
 }
 
 Widget* NavigationView::view() const {
@@ -148,12 +167,18 @@ SystemView::SystemView(
 		{ 0, 0 },
 		{ parent_rect.width(), status_view_height }
 	});
+	status_view.on_back = [this]() {
+		this->navigation_view.pop();
+	};
 
 	add_child(&navigation_view);
 	navigation_view.set_parent_rect({
 		{ 0, status_view_height },
 		{ parent_rect.width(), static_cast<ui::Dim>(parent_rect.height() - status_view_height) }
 	});
+	navigation_view.on_view_changed = [this]() {
+		this->status_view.set_back_visible(!this->navigation_view.is_top());
+	};
 
 	// Initial view.
 	// TODO: Restore from non-volatile memory?

firmware/application/ui_navigation.hpp

@@ -39,11 +39,20 @@ namespace ui {
 
 class SystemStatusView : public View {
 public:
+	std::function<void(void)> on_back;
+
 	SystemStatusView();
 
+	void set_back_visible(bool new_value);
+
 private:
+	Button button_back {
+		{ 0 * 8, 0 * 16, 3 * 8, 16 },
+		" < ",
+	};
+
 	Text portapack {
-		{ 0, 0, 9 * 8, 1 * 16 },
+		{ 3 * 8, 0, 9 * 8, 1 * 16 },
 		"PortaPack",
 	};
 
@@ -52,11 +61,15 @@ private:
 
 class NavigationView : public View {
 public:
+	std::function<void(void)> on_view_changed;
+
 	NavigationView() { }
 
 	NavigationView(const NavigationView&) = delete;
 	NavigationView(NavigationView&&) = delete;
 
+	bool is_top() const;
+
 	template<class T, class... Args>
 	T* push(Args&&... args) {
 		return reinterpret_cast<T*>(push_view(std::unique_ptr<View>(new T(*this, std::forward<Args>(args)...))));

firmware/application/ui_receiver.cpp

@@ -369,7 +369,6 @@ ReceiverView::ReceiverView(
 		&rssi,
 		&channel,
 		&audio,
-		&button_done,
 		&field_frequency,
 		&field_lna,
 		//&options_baseband_bandwidth,
@@ -381,10 +380,6 @@ ReceiverView::ReceiverView(
 		&view_rf_gain_options,
 	} });
 
-	button_done.on_select = [&nav](Button&){
-		nav.pop();
-	};
-
 	field_frequency.set_value(receiver_model.tuning_frequency());
 	field_frequency.set_step(receiver_model.frequency_step());
 	field_frequency.on_change = [this](rf::Frequency f) {
@@ -480,7 +475,7 @@ void ReceiverView::on_hide() {
 }
 
 void ReceiverView::focus() {
-	button_done.focus();
+	field_frequency.focus();
 }
 
 void ReceiverView::on_tuning_frequency_changed(rf::Frequency f) {

firmware/application/ui_receiver.hpp

@@ -375,11 +375,6 @@ private:
 		{ 19 * 8, 10, 11 * 8, 4 },
 	};
 
-	Button button_done {
-		{ 0 * 8, 0 * 16, 3 * 8, 16 },
-		" < ",
-	};
-
 	FrequencyField field_frequency {
 		{ 0 * 8, 1 * 16 },
 	};