[Escher] Add a Container that lets us run multiple apps

Change-Id: I674348ed0ff48934eb248dc48735f4ba13c34692

apps/Makefile

@@ -2,6 +2,7 @@ include apps/graph/Makefile
 #include apps/picview/Makefile
 
 app_objs += $(addprefix apps/,\
+  apps_container.o\
   main.o\
 )
 

apps/apps_container.cpp

@@ -0,0 +1,34 @@
+#include "apps_container.h"
+
+AppsContainer::AppsContainer() :
+  Container()
+{
+}
+
+bool AppsContainer::handleEvent(ion_event_t event) {
+  if (event == F1) {
+#if USE_PIC_VIEW_APP
+    if (activeApp() == &m_picViewApp) {
+      Container::switchTo(&m_graphApp);
+    } else {
+      Container::switchTo(&m_picViewApp);
+    }
+#endif
+    return true;
+  }
+  return false;
+}
+
+void AppsContainer::switchTo(AppId appId) {
+  Container::switchTo(appWithId(appId));
+}
+
+App * AppsContainer::appWithId(AppId appId) {
+  App * apps[] = {
+    &m_graphApp
+#if USE_PIC_VIEW_APP
+    , &m_picViewApp
+#endif
+  };
+  return apps[(int)appId];
+};

apps/apps_container.h

@@ -0,0 +1,27 @@
+#ifndef APPS_CONTAINER_H
+#define APPS_CONTAINER_H
+
+#include "graph/graph_app.h"
+#define USE_PIC_VIEW_APP 0
+#if USE_PIC_VIEW_APP
+#include "picview/picview_app.h"
+#endif
+
+class AppsContainer : public Container {
+public:
+  AppsContainer();
+  enum class AppId {
+    Graph = 0,
+    PicView = 1
+  };
+  void switchTo(AppId appId);
+  bool handleEvent(ion_event_t event) override;
+private:
+  App * appWithId(AppId appId);
+  GraphApp m_graphApp;
+#if USE_PIC_VIEW_APP
+  PicViewApp m_picViewApp;
+#endif
+};
+
+#endif

apps/main.cpp

@@ -1,15 +1,7 @@
-#include "graph/graph_app.h"
-
-#define USE_PIC_VIEW_APP 0
-#if USE_PIC_VIEW_APP
-#include "picview/picview_app.h"
-#endif
+#include "apps_container.h"
 
 void ion_app() {
-#if USE_PIC_VIEW_APP
-  PicViewApp picViewApp = PicViewApp();
-  picViewApp.run();
-#endif
-  GraphApp graphApp = GraphApp();
-  graphApp.run();
+  AppsContainer container;
+  container.switchTo(AppsContainer::AppId::Graph);
+  container.run();
 }

apps/picview/picview_app.cpp

@@ -2,7 +2,7 @@
 
 PicViewApp::PicViewApp() :
   App(),
-  m_picViewController(PicViewController())
+  m_picViewController(PicViewController(this))
 {
 }
 

apps/picview/picview_controller.cpp

@@ -1,7 +1,7 @@
 #include "picview_controller.h"
 
-PicViewController::PicViewController() :
-  ViewController(),
+PicViewController::PicViewController(Responder * parentResponder) :
+  ViewController(parentResponder),
   m_view(PicView())
 {
 }

apps/picview/picview_controller.h

@@ -6,7 +6,7 @@
 
 class PicViewController : public ViewController {
 public:
-  PicViewController();
+  PicViewController(Responder * parentResponder);
   View * view() override;
 private:
   PicView m_view;

escher/Makefile

@@ -3,6 +3,7 @@ SFLAGS += -Iescher/include
 objs += $(addprefix escher/src/,\
   app.o\
   childless_view.o\
+  container.o\
   responder.o\
   scroll_view.o\
   scroll_view_indicator.o\

escher/include/escher.h

@@ -2,6 +2,7 @@
 #define ESCHER_H
 
 #include <escher/app.h>
+#include <escher/container.h>
 #include <escher/responder.h>
 #include <escher/scroll_view.h>
 #include <escher/scroll_view_indicator.h>

escher/include/escher/app.h

@@ -4,26 +4,25 @@
 #include <escher/responder.h>
 #include <escher/view_controller.h>
 
+/* An app is fed events and outputs drawing calls.
+ *
+ * To achieve this, it uses a View hierarchy, and modifies it according to the
+ * events received. The View hierarchy keeps a memory of the area that needs to
+ * be redrawn depending on how it's been modified.
+ *
+ * Multiple App can exist at once.
+ * */
+
 class App : public Responder {
 public:
   App();
-  void run();
+  void setWindow(Window * window);
   void focus(Responder * responder);
+  void processEvent(ion_event_t event);
 protected:
   virtual ViewController * rootViewController() = 0;
 private:
-  void dispatchEvent(ion_event_t event);
   Responder * m_focusedResponder;
 };
 
-/*
-
-void handleEvent(event) {
-  // BACK: I want to do stuff!
-   1/ Reset my text to what it was "before"
-   2/ dismiss
-   dismiss = app->focus(parentResponder());
-}
-*/
-
 #endif

escher/include/escher/container.h

@@ -0,0 +1,32 @@
+#ifndef ESCHER_CONTAINER_H
+#define ESCHER_CONTAINER_H
+
+/* Container is the entry point of a program using Escher.
+ *
+ * A container contains one or multiple App, and is responsible for running them
+ * together. Currently Container displays a single App fullscreen, but can
+ * switch to any other App.
+ *
+ * When writing an Escher program, you typically subclass Container, and your
+ * subclass owns one or more App. You then call "run()" on your container. */
+
+#include <escher/app.h>
+#include <escher/window.h>
+extern "C" {
+#include <ion.h>
+}
+
+class Container {
+public:
+  Container();
+  void run();
+  App * activeApp();
+  virtual bool handleEvent(ion_event_t event);
+protected:
+  void switchTo(App * app);
+private:
+  App * m_activeApp;
+  Window m_window;
+};
+
+#endif

escher/include/escher/tab_view_controller.h

@@ -40,7 +40,7 @@ private:
   static constexpr uint8_t k_maxNumberOfChildren = 4;
   ViewController * m_children[k_maxNumberOfChildren];
   uint8_t m_numberOfChildren;
-  uint8_t m_activeChildIndex;
+  int8_t m_activeChildIndex;
 };
 
 #endif

escher/src/app.cpp

@@ -2,6 +2,7 @@
 #include <escher/window.h>
 extern "C" {
 #include <ion.h>
+#include <assert.h>
 }
 
 App::App() :
@@ -10,26 +11,21 @@ App::App() :
 {
 }
 
-void App::run() {
-  Window window;
-  window.setFrame(KDRect(0, 0, ION_SCREEN_WIDTH, ION_SCREEN_HEIGHT));
-  View * rootView = rootViewController()->view();
-
-  focus(rootViewController());
-
-  window.setContentView(rootView);
-  rootView->setFrame(window.bounds());
-
-  window.redraw();
-
-  while (true) {
-    ion_event_t event = ion_get_event(); // This is a blocking call
-    dispatchEvent(event);
-    window.redraw();
+void App::setWindow(Window * window) {
+  ViewController * controller = rootViewController();
+  View * view = controller->view();
+  if (m_focusedResponder == nullptr) {
+    focus(controller);
   }
+  assert(controller->app() == this);
+
+  window->setContentView(view);
+  view->setFrame(window->bounds());
+
+  window->redraw();
 }
 
-void App::dispatchEvent(ion_event_t event) {
+void App::processEvent(ion_event_t event) {
   Responder * responder = m_focusedResponder;
   bool didHandleEvent = false;
   while (responder) {

escher/src/container.cpp

@@ -0,0 +1,37 @@
+#include <escher/container.h>
+extern "C" {
+#include <ion.h>
+}
+
+Container::Container() :
+  m_activeApp(nullptr)
+{
+}
+
+void Container::switchTo(App * app) {
+  m_activeApp = app;
+  m_activeApp->setWindow(&m_window);
+  m_window.redraw();
+}
+
+App * Container::activeApp() {
+  return m_activeApp;
+}
+
+bool Container::handleEvent(ion_event_t event) {
+  return false;
+}
+
+void Container::run() {
+  m_window.setFrame(KDRect(0, 0, ION_SCREEN_WIDTH, ION_SCREEN_HEIGHT));
+  m_window.redraw();
+
+  while (true) {
+    ion_event_t event = ion_get_event(); // This is a blocking call
+    if (handleEvent(event)) {
+      continue;
+    }
+    m_activeApp->processEvent(event);
+    m_window.redraw();
+  }
+}

escher/src/tab_view_controller.cpp

@@ -116,7 +116,9 @@ void TabViewController::setActiveTab(uint8_t i) {
 View * TabViewController::view() {
   // We're asked for a view!
   // Let's populate our tabview
-  setActiveTab(0);
+  if (m_activeChildIndex < 0) {
+    setActiveTab(0);
+  }
 
   return &m_view;
 }