ash: Extract animator from PowerButtonController

ash/wm/session_state_animator.h

+// Copyright (c) 2012 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 ASH_WM_SESSION_STATE_ANIMATOR_H_
+#define ASH_WM_SESSION_STATE_ANIMATOR_H_
+
+#include "ash/ash_export.h"
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/time.h"
+#include "base/timer.h"
+#include "ui/aura/root_window_observer.h"
+#include "ui/aura/window.h"
+
+namespace gfx {
+class Rect;
+class Size;
+}
+
+namespace ui {
+class Layer;
+}
+
+namespace ash {

[Daniel Erat, 2012/09/28 15:00:43]

nit: can this go inside of ash::internal?

+
+// Displays onscreen animations for session state changes (lock/unlock, sign
+// out, shut down).
+class ASH_EXPORT SessionStateAnimator : public aura::RootWindowObserver {

[Daniel Erat, 2012/09/28 15:00:43]

nit: is ASH_EXPORT actually needed here?  (i'm not sure one way or the other;
maybe it is for tests)

+ public:
+  // Animations that can be applied to groups of containers.
+  enum AnimationType {
+    ANIMATION_SLOW_CLOSE = 0,
+    ANIMATION_UNDO_SLOW_CLOSE,
+    ANIMATION_FAST_CLOSE,
+    ANIMATION_FADE_IN,
+    ANIMATION_HIDE,
+    ANIMATION_RESTORE,
+  };
+
+  // Specific containers or groups of containers that can be animated.
+  enum Container {
+    DESKTOP_BACKGROUND = 1 << 0,
+
+    // All user session related containers including system background but
+    // not including desktop background (wallpaper).
+    NON_LOCK_SCREEN_CONTAINERS = 1 << 1,
+
+    // Desktop wallpaper is moved to this layer when screen is locked.
+    // This layer is excluded from lock animation so that wallpaper stays as is,
+    // user session windows are hidden and lock UI is shown on top of it.
+    // This layer is included in shutdown animation.
+    LOCK_SCREEN_BACKGROUND = 1 << 2,
+
+    // Lock screen and lock screen modal containers.
+    LOCK_SCREEN_CONTAINERS = 1 << 3,
+
+    // Multiple system layers belong here like status, menu, tooltip
+    // and overlay layers.
+    LOCK_SCREEN_RELATED_CONTAINERS = 1 << 4,
+  };
+
+  // Helper class used by tests to access internal state.
+  class ASH_EXPORT TestApi {
+   public:
+    explicit TestApi(SessionStateAnimator* animator)
+        : animator_(animator) {}
+
+    bool hide_black_layer_timer_is_running() const {
+      return animator_->hide_black_layer_timer_.IsRunning();
+    }
+
+    void TriggerHideBlackLayerTimeout();
+
+    // Returns true if containers of a given |container_mask|
+    // were last animated with |type| (probably; the analysis is fairly ad-hoc).
+    // |container_mask| is a bitfield of a Container.
+    bool ContainersAreAnimated(int container_mask, AnimationType type) const;
+
+    // Returns true if |black_layer_| is non-NULL and visible.
+    bool BlackLayerIsVisible() const;
+
+    // Returns |black_layer_|'s bounds, or an empty rect if the layer is
+    // NULL.
+    gfx::Rect GetBlackLayerBounds() const;
+
+   private:
+    SessionStateAnimator* animator_;  // not owned
+
+    DISALLOW_COPY_AND_ASSIGN(TestApi);
+  };
+
+  // Helper method that returns a bitfield mask of all containers.
+  static int GetAllContainersMask();

[Daniel Erat, 2012/09/28 15:00:43]

nit: instead of static methods, this and GetAllLockScreenContainersMask() seem
like they can just be static constant variables, e.g. kAllContainersMask and
kAllLockScreenContainersMask

+
+  // Helper method that returns a bitfield mask including LOCK_SCREEN_WALLPAPER,
+  // LOCK_SCREEN_CONTAINERS, and LOCK_SCREEN_RELATED_CONTAINERS.
+  static int GetAllLockScreenContainersMask();
+
+  SessionStateAnimator();
+  virtual ~SessionStateAnimator();
+
+  // Shows or hides |black_layer_|.  The show method creates and
+  // initializes the layer if it doesn't already exist.
+  void ShowBlackLayer();
+  void DropBlackLayer();
+
+  // Drops back layer after |UNDO_SLOW_CLOSE| animation delay.
+  void ScheduleDropBlackLayer();
+
+   // Apply animation |type| to all containers included in |container_mask|.
+  void StartAnimation(int container_mask,
+                      AnimationType type);
+
+  // Fills |containers| with the containers included in |container_mask|.
+  void GetContainers(int container_mask,
+                     aura::Window::Windows* containers);
+
+  // aura::RootWindowObserver overrides:
+  virtual void OnRootWindowResized(const aura::RootWindow* root,
+                                   const gfx::Size& old_size) OVERRIDE;

[Daniel Erat, 2012/09/28 15:00:43]

nit: add a blank line after this

+ private:
+  // Layer that's stacked under all of the root window's children to provide a
+  // black background when we're scaling all of the other windows down.
+  // TODO(derat): Remove this in favor of having the compositor only clear the
+  // viewport when there are regions not covered by a layer:
+  // http://crbug.com/113445
+  scoped_ptr<ui::Layer> black_layer_;
+
+  // Started when we abort the pre-lock state.  When it fires, we hide
+  // |black_layer_|, as the desktop background is now covering the whole
+  // screen.
+  base::OneShotTimer<SessionStateAnimator> hide_black_layer_timer_;
+
+  DISALLOW_COPY_AND_ASSIGN(SessionStateAnimator);
+};
+
+}  // namespace ash
+
+#endif  // ASH_WM_SESSION_STATE_ANIMATOR_H_