[Escher] Responder can get a pointer to the parent App

We assume the root parent is the App. This works well because each view
controller is a Responder.

Change-Id: I5d90053949a4ffbdb78746cc85430a15138e48e7

apps/graph/graph/graph_controller.cpp

@@ -1,7 +1,7 @@
 #include "graph_controller.h"
 
-GraphController::GraphController() :
-  ViewController(),
+GraphController::GraphController(Responder * parentResponder) :
+  ViewController(parentResponder),
   m_view(GraphView())
 {
 }

apps/graph/graph/graph_controller.h

@@ -6,7 +6,7 @@
 
 class GraphController : public ViewController {
 public:
-  GraphController();
+  GraphController(Responder * parentResponder);
   View * view() override;
   const char * title() const override;
   void setFocused(bool focused) override;

apps/graph/graph_app.cpp

@@ -2,9 +2,9 @@
 
 GraphApp::GraphApp() :
   App(),
-  m_listController(ListController()),
-  m_graphController(GraphController()),
-  m_tabViewController(&m_listController, &m_graphController)
+  m_listController(ListController(nullptr)),
+  m_graphController(GraphController(nullptr)),
+  m_tabViewController(this, &m_listController, &m_graphController)
 {
 }
 

apps/graph/list/function_cell.cpp

@@ -2,6 +2,7 @@
 
 FunctionCell::FunctionCell() :
   ChildlessView(),
+  Responder(nullptr),
   m_focused(false),
   m_even(false)
 {

apps/graph/list/list_controller.cpp

@@ -8,8 +8,8 @@ static const char * sMessages[] = {
   "PPP15", "QQQ16", "RRR17", "SSS18", "TTT19"
 };
 
-ListController::ListController() :
-  ViewController(),
+ListController::ListController(Responder * parentResponder) :
+  ViewController(parentResponder),
   m_tableView(TableView(this)),
   m_activeCell(0),
   m_manualScrolling(0)

apps/graph/list/list_controller.h

@@ -6,7 +6,7 @@
 
 class ListController : public ViewController, public TableViewDataSource {
 public:
-  ListController();
+  ListController(Responder * parentResponder);
 
   void setActiveCell(int index);
 

escher/include/escher/app.h

@@ -4,7 +4,7 @@
 #include <escher/responder.h>
 #include <escher/view_controller.h>
 
-class App {
+class App : public Responder {
 public:
   App();
   static App * runningApp();

escher/include/escher/responder.h

@@ -5,13 +5,16 @@ extern "C" {
 #include <ion.h>
 }
 
+class App;
+
 class Responder {
 public:
-  Responder();
+  Responder(Responder * parentResponder);
   virtual bool handleEvent(ion_event_t event); // Default implementation does nothing
   virtual void setFocused(bool focused); // Default implementation does nothing. Used by subclasses to know when active or not
-  Responder * parentResponder();
+  Responder * parentResponder() const;
   void setParentResponder(Responder * responder);
+  App * app();
 private:
   Responder * m_parentResponder;
 };

escher/include/escher/tab_view_controller.h

@@ -6,7 +6,7 @@
 
 class TabViewController : public ViewController {
 public:
-  TabViewController(ViewController * one, ViewController * two);
+  TabViewController(Responder * parentResponder, ViewController * one, ViewController * two);
   //TabViewController(ViewController ** children, uint8_t numberOfChildren);
   View * view() override;
   void handleKeyEvent(int key) override;

escher/include/escher/text_field.h

@@ -7,7 +7,7 @@
 
 class TextField : public ChildlessView, public Responder {
 public:
-  TextField(char * textBuffer, size_t textBufferSize);
+  TextField(Responder * parentResponder, char * textBuffer, size_t textBufferSize);
   // View
   void drawRect(KDContext * ctx, KDRect rect) const override;
   // Responder

escher/include/escher/view_controller.h

@@ -16,7 +16,7 @@ extern "C" {
 
 class ViewController : public Responder {
 public:
-  ViewController();
+  ViewController(Responder * parentResponder);
   virtual const char * title() const;
   virtual void handleKeyEvent(int key);
   virtual View * view() = 0;

escher/src/app.cpp

@@ -7,6 +7,7 @@ extern "C" {
 static App * sRunningApp = nullptr;
 
 App::App() :
+  Responder(nullptr),
   m_focusedResponder(nullptr)
 {
 }

escher/src/responder.cpp

@@ -1,11 +1,11 @@
 #include <escher/responder.h>
 
-Responder::Responder() :
-  m_parentResponder(nullptr)
+Responder::Responder(Responder * parentResponder) :
+  m_parentResponder(parentResponder)
 {
 }
 
-Responder * Responder::parentResponder() {
+Responder * Responder::parentResponder() const {
   return m_parentResponder;
 }
 
@@ -19,3 +19,15 @@ bool Responder::handleEvent(ion_event_t event) {
 
 void Responder::setFocused(bool focused) {
 }
+
+/* We assume the app is the root parent. */
+App * Responder::app() {
+  Responder * rootResponder = this;
+  while (rootResponder->parentResponder() != nullptr) {
+    rootResponder = rootResponder->parentResponder();
+  }
+  /* If we used RTTI we could use a dynamic_cast, which would be a lot more
+   * safe, as such:
+   * return dynamic_cast<App *>(rootResponder); */
+  return (App *)rootResponder;
+}

escher/src/tab_view_controller.cpp

@@ -53,8 +53,8 @@ const char * TabViewController::ContentView::className() const {
 }
 #endif
 
-TabViewController::TabViewController(ViewController * one, ViewController * two) :
-  ViewController(),
+TabViewController::TabViewController(Responder * parentResponder, ViewController * one, ViewController * two) :
+  ViewController(parentResponder),
   m_numberOfChildren(2),
   m_activeChildIndex(-1)
 {

escher/src/text_field.cpp

@@ -1,6 +1,7 @@
 #include <escher/text_field.h>
 
-TextField::TextField(char * textBuffer, size_t textBufferSize) :
+TextField::TextField(Responder * parentResponder, char * textBuffer, size_t textBufferSize) :
+  Responder(parentResponder),
   ChildlessView(),
   m_textBuffer(textBuffer),
   m_textBufferSize(textBufferSize),

escher/src/view_controller.cpp

@@ -1,7 +1,8 @@
 #include <escher/view_controller.h>
 
-ViewController::ViewController() :
-  Responder() {
+ViewController::ViewController(Responder * parentResponder) :
+  Responder(parentResponder)
+{
 }
 
 const char * ViewController::title() const {