athena: A simpler implementation of WindowListProvider.

athena/wm/split_view_controller.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ATHENA_WM_SPLIT_VIEW_CONTROLLER_H_
 #define ATHENA_WM_SPLIT_VIEW_CONTROLLER_H_
 
 #include "athena/athena_export.h"
 #include "athena/wm/bezel_controller.h"
-#include "athena/wm/public/window_manager_observer.h"
-#include "athena/wm/window_overview_mode.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 
 namespace gfx {
 class Transform;
 }
 
 namespace athena {
 class WindowListProvider;
-class WindowManager;
-class WindowOverviewModeDelegate;
 
 // Responsible for entering split view mode, exiting from split view mode, and
 // laying out the windows in split view mode.
 class ATHENA_EXPORT SplitViewController
-    : public BezelController::ScrollDelegate,
-    public WindowManagerObserver {
+    : public BezelController::ScrollDelegate {
  public:
   SplitViewController(aura::Window* container,
-                      WindowListProvider* window_list_provider,
-                      WindowManager* window_manager);
+                      WindowListProvider* window_list_provider);
 
   virtual ~SplitViewController();
 
   bool IsSplitViewModeActive() const;
 
   // Activates split-view mode with |left| and |right| windows. If |left| and/or
   // |right| is NULL, then the first window in the window-list (which is neither
   // |left| nor |right|) is selected instead.
   void ActivateSplitMode(aura::Window* left, aura::Window* right);
 
+  // Resets the internal state to an inactive state. Calling this does not
+  // change the window bounds/transforms etc. The caller must take care of
+  // making any necessary changes.
+  void DeactivateSplitMode();
+
   aura::Window* left_window() { return left_window_; }
   aura::Window* right_window() { return right_window_; }
 
  private:
   enum State {
     // Split View mode is not active. |left_window_| and |right_window| are
     // NULL.
     INACTIVE,
     // Two windows |left_window_| and |right_window| are shown side by side and
     // there is a horizontal scroll in progress which is dragging the separator
     // between the two windows.
     SCROLLING,
     // Split View mode is active with |left_window_| and |right_window| showing
     // side by side each occupying half the screen. No scroll in progress.
     ACTIVE
   };
 
   void UpdateLayout(bool animate);
 
   void SetWindowTransform(aura::Window* left_window,
                           const gfx::Transform& transform,
                           bool animate);
 
   void OnAnimationCompleted(aura::Window* window);
 
   void UpdateSeparatorPositionFromScrollDelta(float delta);
 
-  // Returns the current activity shown to the user. Persists through the
-  // SCROLLING and ACTIVE states and gets updated if the current activity goes
-  // off screen when the user switches between activities.
-  aura::Window* GetCurrentActivityWindow();
-
-  // BezelController::ScrollDelegate overrides.
+  // BezelController::ScrollDelegate:
   virtual void ScrollBegin(BezelController::Bezel bezel, float delta) OVERRIDE;
   virtual void ScrollEnd() OVERRIDE;
   virtual void ScrollUpdate(float delta) OVERRIDE;
   virtual bool CanScroll() OVERRIDE;
 
-  // WindowManagerObserver
-  virtual void OnOverviewModeEnter() OVERRIDE;
-  virtual void OnOverviewModeExit() OVERRIDE;
-
   State state_;
 
   aura::Window* container_;
 
-  // Window Manager which owns this SplitViewController. The window manager must
-  // be alive for the duration of the lifetime of the SplitViewController.
-  // Can be NULL (in tests).
-  WindowManager* window_manager_;
-
   // Provider of the list of windows to cycle through. Not owned.
   WindowListProvider* window_list_provider_;
 
-  // Keeps track of the current activity shown as the user switches between
-  // activities. Persists through the SCROLLING and ACTIVE states. Gets reset
-  // to NULL when overview mode is activated.
-  aura::Window* current_activity_window_;
-
   // Windows for the left and right activities shown in SCROLLING and ACTIVE
   // states. In INACTIVE state these are NULL.
   aura::Window* left_window_;
   aura::Window* right_window_;
 
   // Position of the separator between left_window_ and right_window_ in
   // container_ coordinates (along the x axis).
   int separator_position_;
 
   base::WeakPtrFactory<SplitViewController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SplitViewController);
 };
 
 }  // namespace athena
 
 #endif  // ATHENA_WM_SPLIT_VIEW_CONTROLLER_H_