Split Screen mode implementation.

athena/wm/window_manager_impl.cc

Index: athena/wm/window_manager_impl.cc
diff --git a/athena/wm/window_manager_impl.cc b/athena/wm/window_manager_impl.cc
index 560252aec02a3f9e8a8e69a9a040acbae2b47870..37daf437242a9a79c8a042e3c4521cf90b0632a1 100644
--- a/athena/wm/window_manager_impl.cc
+++ b/athena/wm/window_manager_impl.cc
@@ -10,6 +10,7 @@
 #include "athena/input/public/accelerator_manager.h"
 #include "athena/screen/public/screen_manager.h"
 #include "athena/wm/bezel_controller.h"
+#include "athena/wm/mru_window_tracker.h"
 #include "athena/wm/public/window_manager_observer.h"
 #include "athena/wm/split_view_controller.h"
 #include "athena/wm/title_drag_controller.h"
@@ -41,6 +42,8 @@ class WindowManagerImpl : public WindowManager,
   // WindowManager:
   virtual void ToggleOverview() OVERRIDE;
 
+  virtual bool IsOverviewModeActive() OVERRIDE;
+
  private:
   enum Command {
     CMD_TOGGLE_OVERVIEW,
@@ -74,6 +77,7 @@ class WindowManagerImpl : public WindowManager,
   virtual void OnTitleDragCanceled(aura::Window* window) OVERRIDE;
 
   scoped_ptr<aura::Window> container_;
+  scoped_ptr<MruWindowTracker> mru_window_tracker_;
   scoped_ptr<WindowOverviewMode> overview_;
   scoped_ptr<BezelController> bezel_controller_;
   scoped_ptr<SplitViewController> split_view_controller_;
@@ -112,8 +116,10 @@ WindowManagerImpl::WindowManagerImpl() {
   container_.reset(ScreenManager::Get()->CreateDefaultContainer(params));
   container_->SetLayoutManager(new AthenaContainerLayoutManager);
   container_->AddObserver(this);
+  mru_window_tracker_.reset(new MruWindowTracker(container_.get()));
   bezel_controller_.reset(new BezelController(container_.get()));
-  split_view_controller_.reset(new SplitViewController());
+  split_view_controller_.reset(new SplitViewController(
+      container_.get(), mru_window_tracker_.get(), this));
   bezel_controller_->set_left_right_delegate(split_view_controller_.get());
   container_->AddPreTargetHandler(bezel_controller_.get());
   title_drag_controller_.reset(new TitleDragController(container_.get(), this));
@@ -127,6 +133,7 @@ WindowManagerImpl::WindowManagerImpl() {
 
 WindowManagerImpl::~WindowManagerImpl() {
   overview_.reset();
+  mru_window_tracker_.reset();
   if (container_) {
     container_->RemoveObserver(this);
     container_->RemovePreTargetHandler(bezel_controller_.get());
@@ -154,15 +161,26 @@ void WindowManagerImpl::ToggleOverview() {
   SetInOverview(overview_.get() == NULL);
 }
 
+bool WindowManagerImpl::IsOverviewModeActive() {
+  return overview_;
+}
+
 void WindowManagerImpl::SetInOverview(bool active) {
   bool in_overview = !!overview_;
   if (active == in_overview)
     return;
 
   if (active) {
-    overview_ = WindowOverviewMode::Create(container_.get(), this);
     FOR_EACH_OBSERVER(WindowManagerObserver, observers_,
                       OnOverviewModeEnter());
+    // Re-stack all windows in the order defined by mru_window_tracker_.
+    aura::Window::Windows window_list = mru_window_tracker_->GetWindowList();
+    aura::Window::Windows::iterator it;
+    for (it = window_list.begin(); it != window_list.end(); ++it)
+      container_->StackChildAtTop(*it);
+    overview_ = WindowOverviewMode::Create(container_.get(),
+                                           mru_window_tracker_.get(),
+                                           this);
   } else {
     overview_.reset();
     FOR_EACH_OBSERVER(WindowManagerObserver, observers_,
@@ -188,8 +206,7 @@ void WindowManagerImpl::RemoveObserver(WindowManagerObserver* observer) {
 }
 
 void WindowManagerImpl::OnSelectWindow(aura::Window* window) {
-  CHECK_EQ(container_.get(), window->parent());
-  container_->StackChildAtTop(window);
+  mru_window_tracker_->MoveToFront(window);
   wm::ActivateWindow(window);
   SetInOverview(false);
 }