ash/shelf/shelf_layout_manager.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ash/shelf/shelf_layout_manager.h"
   6
   7 #include <algorithm>
   8 #include <cmath>
   9 #include <cstring>
  10 #include <string>
  11 #include <vector>
  12
  13 #include "ash/accelerators/accelerator_commands.h"
  14 #include "ash/ash_switches.h"
  15 #include "ash/root_window_controller.h"
  16 #include "ash/screen_util.h"
  17 #include "ash/session/session_state_delegate.h"
  18 #include "ash/shelf/shelf.h"
  19 #include "ash/shelf/shelf_bezel_event_filter.h"
  20 #include "ash/shelf/shelf_constants.h"
  21 #include "ash/shelf/shelf_layout_manager_observer.h"
  22 #include "ash/shelf/shelf_widget.h"
  23 #include "ash/shell.h"
  24 #include "ash/shell_window_ids.h"
  25 #include "ash/system/status_area_widget.h"
  26 #include "ash/wm/gestures/shelf_gesture_handler.h"
  27 #include "ash/wm/lock_state_controller.h"
  28 #include "ash/wm/mru_window_tracker.h"
  29 #include "ash/wm/window_animations.h"
  30 #include "ash/wm/window_state.h"
  31 #include "ash/wm/window_util.h"
  32 #include "ash/wm/workspace_controller.h"
  33 #include "base/auto_reset.h"
  34 #include "base/command_line.h"
  35 #include "base/command_line.h"
  36 #include "base/i18n/rtl.h"
  37 #include "base/strings/string_number_conversions.h"
  38 #include "base/strings/string_util.h"
  39 #include "ui/aura/client/cursor_client.h"
  40 #include "ui/aura/window_event_dispatcher.h"
  41 #include "ui/base/ui_base_switches.h"
  42 #include "ui/compositor/layer.h"
  43 #include "ui/compositor/layer_animation_observer.h"
  44 #include "ui/compositor/layer_animator.h"
  45 #include "ui/compositor/scoped_layer_animation_settings.h"
  46 #include "ui/events/event.h"
  47 #include "ui/events/event_handler.h"
  48 #include "ui/gfx/screen.h"
  49 #include "ui/keyboard/keyboard_util.h"
  50 #include "ui/views/widget/widget.h"
  51 #include "ui/wm/public/activation_client.h"
  52
  53 namespace ash {
  54 namespace {
  55
  56 // Delay before showing the shelf. This is after the mouse stops moving.
  57 const int kAutoHideDelayMS = 200;
  58
  59 // To avoid hiding the shelf when the mouse transitions from a message bubble
  60 // into the shelf, the hit test area is enlarged by this amount of pixels to
  61 // keep the shelf from hiding.
  62 const int kNotificationBubbleGapHeight = 6;
  63
  64 // The maximum size of the region on the display opposing the shelf managed by
  65 // this ShelfLayoutManager which can trigger showing the shelf.
  66 // For instance:
  67 // - Primary display is left of secondary display.
  68 // - Shelf is left aligned
  69 // - This ShelfLayoutManager manages the shelf for the secondary display.
  70 // |kMaxAutoHideShowShelfRegionSize| refers to the maximum size of the region
  71 // from the right edge of the primary display which can trigger showing the
  72 // auto hidden shelf. The region is used to make it easier to trigger showing
  73 // the auto hidden shelf when the shelf is on the boundary between displays.
  74 const int kMaxAutoHideShowShelfRegionSize = 10;
  75
  76 ui::Layer* GetLayer(views::Widget* widget) {
  77   return widget->GetNativeView()->layer();
  78 }
  79
  80 }  // namespace
  81
  82 // static
  83 const int ShelfLayoutManager::kWorkspaceAreaVisibleInset = 2;
  84
  85 // static
  86 const int ShelfLayoutManager::kWorkspaceAreaAutoHideInset = 5;
  87
  88 // static
  89 const int ShelfLayoutManager::kAutoHideSize = 3;
  90
  91 // static
  92 const int ShelfLayoutManager::kShelfItemInset = 3;
  93
  94 // ShelfLayoutManager::AutoHideEventFilter -------------------------------------
  95
  96 // Notifies ShelfLayoutManager any time the mouse moves.
  97 class ShelfLayoutManager::AutoHideEventFilter : public ui::EventHandler {
  98  public:
  99   explicit AutoHideEventFilter(ShelfLayoutManager* shelf);
 100   ~AutoHideEventFilter() override;
 101
 102   // Returns true if the last mouse event was a mouse drag.
 103   bool in_mouse_drag() const { return in_mouse_drag_; }
 104
 105   // Overridden from ui::EventHandler:
 106   void OnMouseEvent(ui::MouseEvent* event) override;
 107   void OnGestureEvent(ui::GestureEvent* event) override;
 108
 109  private:
 110   ShelfLayoutManager* shelf_;
 111   bool in_mouse_drag_;
 112   ShelfGestureHandler gesture_handler_;
 113   DISALLOW_COPY_AND_ASSIGN(AutoHideEventFilter);
 114 };
 115
 116 ShelfLayoutManager::AutoHideEventFilter::AutoHideEventFilter(
 117     ShelfLayoutManager* shelf)
 118     : shelf_(shelf),
 119       in_mouse_drag_(false) {
 120   Shell::GetInstance()->AddPreTargetHandler(this);
 121 }
 122
 123 ShelfLayoutManager::AutoHideEventFilter::~AutoHideEventFilter() {
 124   Shell::GetInstance()->RemovePreTargetHandler(this);
 125 }
 126
 127 void ShelfLayoutManager::AutoHideEventFilter::OnMouseEvent(
 128     ui::MouseEvent* event) {
 129   // This also checks IsShelfWindow() to make sure we don't attempt to hide the
 130   // shelf if the mouse down occurs on the shelf.
 131   in_mouse_drag_ = (event->type() == ui::ET_MOUSE_DRAGGED ||
 132                     (in_mouse_drag_ && event->type() != ui::ET_MOUSE_RELEASED &&
 133                      event->type() != ui::ET_MOUSE_CAPTURE_CHANGED)) &&
 134       !shelf_->IsShelfWindow(static_cast<aura::Window*>(event->target()));
 135   if (event->type() == ui::ET_MOUSE_MOVED)
 136     shelf_->UpdateAutoHideState();
 137   return;
 138 }
 139
 140 void ShelfLayoutManager::AutoHideEventFilter::OnGestureEvent(
 141     ui::GestureEvent* event) {
 142   aura::Window* target_window = static_cast<aura::Window*>(event->target());
 143   if (shelf_->IsShelfWindow(target_window)) {
 144     if (gesture_handler_.ProcessGestureEvent(*event, target_window))
 145       event->StopPropagation();
 146   }
 147 }
 148
 149 // ShelfLayoutManager:UpdateShelfObserver --------------------------------------
 150
 151 // UpdateShelfObserver is used to delay updating the background until the
 152 // animation completes.
 153 class ShelfLayoutManager::UpdateShelfObserver
 154     : public ui::ImplicitAnimationObserver {
 155  public:
 156   explicit UpdateShelfObserver(ShelfLayoutManager* shelf) : shelf_(shelf) {
 157     shelf_->update_shelf_observer_ = this;
 158   }
 159
 160   void Detach() {
 161     shelf_ = NULL;
 162   }
 163
 164   void OnImplicitAnimationsCompleted() override {
 165     if (shelf_)
 166       shelf_->UpdateShelfBackground(BACKGROUND_CHANGE_ANIMATE);
 167     delete this;
 168   }
 169
 170  private:
 171   ~UpdateShelfObserver() override {
 172     if (shelf_)
 173       shelf_->update_shelf_observer_ = NULL;
 174   }
 175
 176   // Shelf we're in. NULL if deleted before we're deleted.
 177   ShelfLayoutManager* shelf_;
 178
 179   DISALLOW_COPY_AND_ASSIGN(UpdateShelfObserver);
 180 };
 181
 182 // ShelfLayoutManager ----------------------------------------------------------
 183
 184 ShelfLayoutManager::ShelfLayoutManager(ShelfWidget* shelf)
 185     : SnapToPixelLayoutManager(shelf->GetNativeView()->parent()),
 186       root_window_(shelf->GetNativeView()->GetRootWindow()),
 187       updating_bounds_(false),
 188       auto_hide_behavior_(SHELF_AUTO_HIDE_BEHAVIOR_NEVER),
 189       alignment_(SHELF_ALIGNMENT_BOTTOM),
 190       shelf_(shelf),
 191       workspace_controller_(NULL),
 192       window_overlaps_shelf_(false),
 193       mouse_over_shelf_when_auto_hide_timer_started_(false),
 194       bezel_event_filter_(new ShelfBezelEventFilter(this)),
 195       gesture_drag_status_(GESTURE_DRAG_NONE),
 196       gesture_drag_amount_(0.f),
 197       gesture_drag_auto_hide_state_(SHELF_AUTO_HIDE_SHOWN),
 198       update_shelf_observer_(NULL),
 199       duration_override_in_ms_(0) {
 200   Shell::GetInstance()->AddShellObserver(this);
 201   Shell::GetInstance()->lock_state_controller()->AddObserver(this);
 202   aura::client::GetActivationClient(root_window_)->AddObserver(this);
 203   Shell::GetInstance()->session_state_delegate()->AddSessionStateObserver(this);
 204 }
 205
 206 ShelfLayoutManager::~ShelfLayoutManager() {
 207   if (update_shelf_observer_)
 208     update_shelf_observer_->Detach();
 209
 210   FOR_EACH_OBSERVER(ShelfLayoutManagerObserver, observers_, WillDeleteShelf());
 211   Shell::GetInstance()->RemoveShellObserver(this);
 212   Shell::GetInstance()->lock_state_controller()->RemoveObserver(this);
 213   Shell::GetInstance()->
 214       session_state_delegate()->RemoveSessionStateObserver(this);
 215 }
 216
 217 void ShelfLayoutManager::SetAutoHideBehavior(ShelfAutoHideBehavior behavior) {
 218   if (auto_hide_behavior_ == behavior)
 219     return;
 220   auto_hide_behavior_ = behavior;
 221   UpdateVisibilityState();
 222   FOR_EACH_OBSERVER(ShelfLayoutManagerObserver, observers_,
 223                     OnAutoHideBehaviorChanged(root_window_,
 224                                               auto_hide_behavior_));
 225 }
 226
 227 void ShelfLayoutManager::PrepareForShutdown() {
 228   // Clear all event filters, otherwise sometimes those filters may catch
 229   // synthesized mouse event and cause crashes during the shutdown.
 230   set_workspace_controller(NULL);
 231   auto_hide_event_filter_.reset();
 232   bezel_event_filter_.reset();
 233   // Stop observing window change, otherwise we can attempt to update a
 234   // partially destructed shelf.
 235   aura::client::GetActivationClient(root_window_)->RemoveObserver(this);
 236 }
 237
 238 bool ShelfLayoutManager::IsVisible() const {
 239   // status_area_widget() may be NULL during the shutdown.
 240   return shelf_->status_area_widget() &&
 241       shelf_->status_area_widget()->IsVisible() &&
 242       (state_.visibility_state == SHELF_VISIBLE ||
 243        (state_.visibility_state == SHELF_AUTO_HIDE &&
 244         state_.auto_hide_state == SHELF_AUTO_HIDE_SHOWN));
 245 }
 246
 247 bool ShelfLayoutManager::SetAlignment(ShelfAlignment alignment) {
 248   if (alignment_ == alignment)
 249     return false;
 250
 251   alignment_ = alignment;
 252   // The shelf will itself move to the bottom while locked or obscured by user
 253   // login. If a request is sent to move while being obscured, we postpone the
 254   // move until the user session is resumed.
 255   if (IsAlignmentLocked())
 256     return false;
 257
 258   // This should not be called during the lock screen transitions.
 259   shelf_->SetAlignment(alignment);
 260   LayoutShelf();
 261   return true;
 262 }
 263
 264 ShelfAlignment ShelfLayoutManager::GetAlignment() const {
 265   // When the screen is locked or a user gets added, the shelf is forced into
 266   // bottom alignment.
 267   if (IsAlignmentLocked())
 268     return SHELF_ALIGNMENT_BOTTOM;
 269   return alignment_;
 270 }
 271
 272 gfx::Rect ShelfLayoutManager::GetIdealBounds() {
 273   gfx::Rect bounds(
 274       ScreenUtil::GetDisplayBoundsInParent(shelf_->GetNativeView()));
 275   int width = 0, height = 0;
 276   GetShelfSize(&width, &height);
 277   return SelectValueForShelfAlignment(
 278       gfx::Rect(bounds.x(), bounds.bottom() - height, bounds.width(), height),
 279       gfx::Rect(bounds.x(), bounds.y(), width, bounds.height()),
 280       gfx::Rect(bounds.right() - width, bounds.y(), width, bounds.height()),
 281       gfx::Rect(bounds.x(), bounds.y(), bounds.width(), height));
 282 }
 283
 284 void ShelfLayoutManager::LayoutShelf() {
 285   TargetBounds target_bounds;
 286   CalculateTargetBounds(state_, &target_bounds);
 287   UpdateBoundsAndOpacity(target_bounds, false, NULL);
 288
 289   if (shelf_->shelf()) {
 290     // This is not part of UpdateBoundsAndOpacity() because
 291     // SetShelfViewBounds() sets the bounds immediately and does not animate.
 292     // The height of the ShelfView for a horizontal shelf and the width of
 293     // the ShelfView for a vertical shelf are set when |shelf_|'s bounds
 294     // are changed via UpdateBoundsAndOpacity(). This sets the origin and the
 295     // dimension in the other direction.
 296     shelf_->shelf()->SetShelfViewBounds(
 297         target_bounds.shelf_bounds_in_shelf);
 298     // Update insets in ShelfWindowTargeter when shelf bounds change.
 299     FOR_EACH_OBSERVER(ShelfLayoutManagerObserver, observers_,
 300                       WillChangeVisibilityState(visibility_state()));
 301   }
 302 }
 303
 304 ShelfVisibilityState ShelfLayoutManager::CalculateShelfVisibility() {
 305   switch(auto_hide_behavior_) {
 306     case SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS:
 307 #if defined(OS_WIN)
 308       // Disable shelf auto-hide behavior on screen sides in Metro mode.
 309       if (GetAlignment() != SHELF_ALIGNMENT_BOTTOM)
 310         return SHELF_VISIBLE;
 311 #endif
 312       return SHELF_AUTO_HIDE;
 313     case SHELF_AUTO_HIDE_BEHAVIOR_NEVER:
 314       return SHELF_VISIBLE;
 315     case SHELF_AUTO_HIDE_ALWAYS_HIDDEN:
 316       return SHELF_HIDDEN;
 317   }
 318   return SHELF_VISIBLE;
 319 }
 320
 321 void ShelfLayoutManager::UpdateVisibilityState() {
 322   // Bail out early when there is no |workspace_controller_|, which happens
 323   // during shutdown after PrepareForShutdown.
 324   if (!workspace_controller_)
 325     return;
 326
 327   if (state_.is_screen_locked || state_.is_adding_user_screen) {
 328     SetState(SHELF_VISIBLE);
 329   } else {
 330     // TODO(zelidrag): Verify shelf drag animation still shows on the device
 331     // when we are in SHELF_AUTO_HIDE_ALWAYS_HIDDEN.
 332     WorkspaceWindowState window_state(workspace_controller_->GetWindowState());
 333     switch (window_state) {
 334       case WORKSPACE_WINDOW_STATE_FULL_SCREEN: {
 335         const aura::Window* fullscreen_window = GetRootWindowController(
 336             root_window_)->GetWindowForFullscreenMode();
 337         if (fullscreen_window && wm::GetWindowState(fullscreen_window)->
 338                 hide_shelf_when_fullscreen()) {
 339           SetState(SHELF_HIDDEN);
 340         } else {
 341           // The shelf is sometimes not hidden when in immersive fullscreen.
 342           // Force the shelf to be auto hidden in this case.
 343           SetState(SHELF_AUTO_HIDE);
 344         }
 345         break;
 346       }
 347
 348       case WORKSPACE_WINDOW_STATE_MAXIMIZED:
 349         SetState(CalculateShelfVisibility());
 350         break;
 351
 352       case WORKSPACE_WINDOW_STATE_WINDOW_OVERLAPS_SHELF:
 353       case WORKSPACE_WINDOW_STATE_DEFAULT:
 354         SetState(CalculateShelfVisibility());
 355         SetWindowOverlapsShelf(window_state ==
 356                                WORKSPACE_WINDOW_STATE_WINDOW_OVERLAPS_SHELF);
 357         break;
 358     }
 359   }
 360 }
 361
 362 void ShelfLayoutManager::UpdateAutoHideState() {
 363   ShelfAutoHideState auto_hide_state =
 364       CalculateAutoHideState(state_.visibility_state);
 365   if (auto_hide_state != state_.auto_hide_state) {
 366     if (auto_hide_state == SHELF_AUTO_HIDE_HIDDEN) {
 367       // Hides happen immediately.
 368       SetState(state_.visibility_state);
 369     } else {
 370       if (!auto_hide_timer_.IsRunning()) {
 371         mouse_over_shelf_when_auto_hide_timer_started_ =
 372             shelf_->GetWindowBoundsInScreen().Contains(
 373                 Shell::GetScreen()->GetCursorScreenPoint());
 374       }
 375       auto_hide_timer_.Start(
 376           FROM_HERE,
 377           base::TimeDelta::FromMilliseconds(kAutoHideDelayMS),
 378           this, &ShelfLayoutManager::UpdateAutoHideStateNow);
 379     }
 380   } else {
 381     StopAutoHideTimer();
 382   }
 383 }
 384
 385 void ShelfLayoutManager::SetWindowOverlapsShelf(bool value) {
 386   window_overlaps_shelf_ = value;
 387   UpdateShelfBackground(BACKGROUND_CHANGE_ANIMATE);
 388 }
 389
 390 void ShelfLayoutManager::AddObserver(ShelfLayoutManagerObserver* observer) {
 391   observers_.AddObserver(observer);
 392 }
 393
 394 void ShelfLayoutManager::RemoveObserver(ShelfLayoutManagerObserver* observer) {
 395   observers_.RemoveObserver(observer);
 396 }
 397
 398 ////////////////////////////////////////////////////////////////////////////////
 399 // ShelfLayoutManager, Gesture functions:
 400
 401 void ShelfLayoutManager::OnGestureEdgeSwipe(const ui::GestureEvent& gesture) {
 402   if (visibility_state() == SHELF_AUTO_HIDE) {
 403     gesture_drag_auto_hide_state_ = SHELF_AUTO_HIDE_SHOWN;
 404     gesture_drag_status_ = GESTURE_DRAG_COMPLETE_IN_PROGRESS;
 405     UpdateVisibilityState();
 406     gesture_drag_status_ = GESTURE_DRAG_NONE;
 407   }
 408 }
 409
 410 void ShelfLayoutManager::StartGestureDrag(const ui::GestureEvent& gesture) {
 411   gesture_drag_status_ = GESTURE_DRAG_IN_PROGRESS;
 412   gesture_drag_amount_ = 0.f;
 413   gesture_drag_auto_hide_state_ = visibility_state() == SHELF_AUTO_HIDE ?
 414       auto_hide_state() : SHELF_AUTO_HIDE_SHOWN;
 415   UpdateShelfBackground(BACKGROUND_CHANGE_ANIMATE);
 416 }
 417
 418 void ShelfLayoutManager::UpdateGestureDrag(
 419     const ui::GestureEvent& gesture) {
 420   bool horizontal = IsHorizontalAlignment();
 421   gesture_drag_amount_ += horizontal ? gesture.details().scroll_y() :
 422                                        gesture.details().scroll_x();
 423   LayoutShelf();
 424 }
 425
 426 void ShelfLayoutManager::CompleteGestureDrag(const ui::GestureEvent& gesture) {
 427   bool horizontal = IsHorizontalAlignment();
 428   bool should_change = false;
 429   if (gesture.type() == ui::ET_GESTURE_SCROLL_END) {
 430     // The visibility of the shelf changes only if the shelf was dragged X%
 431     // along the correct axis. If the shelf was already visible, then the
 432     // direction of the drag does not matter.
 433     const float kDragHideThreshold = 0.4f;
 434     gfx::Rect bounds = GetIdealBounds();
 435     float drag_ratio = fabs(gesture_drag_amount_) /
 436                        (horizontal ?  bounds.height() : bounds.width());
 437     if (gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_SHOWN) {
 438       should_change = drag_ratio > kDragHideThreshold;
 439     } else {
 440       bool correct_direction = false;
 441       switch (GetAlignment()) {
 442         case SHELF_ALIGNMENT_BOTTOM:
 443         case SHELF_ALIGNMENT_RIGHT:
 444           correct_direction = gesture_drag_amount_ < 0;
 445           break;
 446         case SHELF_ALIGNMENT_LEFT:
 447         case SHELF_ALIGNMENT_TOP:
 448           correct_direction = gesture_drag_amount_ > 0;
 449           break;
 450       }
 451       should_change = correct_direction && drag_ratio > kDragHideThreshold;
 452     }
 453   } else if (gesture.type() == ui::ET_SCROLL_FLING_START) {
 454     if (gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_SHOWN) {
 455       should_change = horizontal ? fabs(gesture.details().velocity_y()) > 0 :
 456                                    fabs(gesture.details().velocity_x()) > 0;
 457     } else {
 458       should_change = SelectValueForShelfAlignment(
 459           gesture.details().velocity_y() < 0,
 460           gesture.details().velocity_x() > 0,
 461           gesture.details().velocity_x() < 0,
 462           gesture.details().velocity_y() > 0);
 463     }
 464   } else {
 465     NOTREACHED();
 466   }
 467
 468   if (!should_change) {
 469     CancelGestureDrag();
 470     return;
 471   }
 472   if (shelf_) {
 473     shelf_->Deactivate();
 474     shelf_->status_area_widget()->Deactivate();
 475   }
 476   gesture_drag_auto_hide_state_ =
 477       gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_SHOWN ?
 478       SHELF_AUTO_HIDE_HIDDEN : SHELF_AUTO_HIDE_SHOWN;
 479   ShelfAutoHideBehavior new_auto_hide_behavior =
 480       gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_SHOWN ?
 481       SHELF_AUTO_HIDE_BEHAVIOR_NEVER : SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS;
 482
 483   // When in fullscreen and the shelf is forced to be auto hidden, the auto hide
 484   // behavior affects neither the visibility state nor the auto hide state. Set
 485   // |gesture_drag_status_| to GESTURE_DRAG_COMPLETE_IN_PROGRESS to set the auto
 486   // hide state to |gesture_drag_auto_hide_state_|.
 487   gesture_drag_status_ = GESTURE_DRAG_COMPLETE_IN_PROGRESS;
 488   if (auto_hide_behavior_ != new_auto_hide_behavior)
 489     SetAutoHideBehavior(new_auto_hide_behavior);
 490   else
 491     UpdateVisibilityState();
 492   gesture_drag_status_ = GESTURE_DRAG_NONE;
 493 }
 494
 495 void ShelfLayoutManager::CancelGestureDrag() {
 496   gesture_drag_status_ = GESTURE_DRAG_CANCEL_IN_PROGRESS;
 497   UpdateVisibilityState();
 498   gesture_drag_status_ = GESTURE_DRAG_NONE;
 499 }
 500
 501 void ShelfLayoutManager::SetAnimationDurationOverride(
 502     int duration_override_in_ms) {
 503   duration_override_in_ms_ = duration_override_in_ms;
 504 }
 505
 506 ////////////////////////////////////////////////////////////////////////////////
 507 // ShelfLayoutManager, aura::LayoutManager implementation:
 508
 509 void ShelfLayoutManager::OnWindowResized() {
 510   LayoutShelf();
 511 }
 512
 513 void ShelfLayoutManager::SetChildBounds(aura::Window* child,
 514                                         const gfx::Rect& requested_bounds) {
 515   SnapToPixelLayoutManager::SetChildBounds(child, requested_bounds);
 516   // We may contain other widgets (such as frame maximize bubble) but they don't
 517   // effect the layout in anyway.
 518   if (!updating_bounds_ &&
 519       ((shelf_->GetNativeView() == child) ||
 520        (shelf_->status_area_widget()->GetNativeView() == child))) {
 521     LayoutShelf();
 522   }
 523 }
 524
 525 void ShelfLayoutManager::OnLockStateChanged(bool locked) {
 526   // Force the shelf to layout for alignment (bottom if locked, restore
 527   // the previous alignment otherwise).
 528   state_.is_screen_locked = locked;
 529   UpdateShelfVisibilityAfterLoginUIChange();
 530 }
 531
 532 void ShelfLayoutManager::OnWindowActivated(
 533     aura::client::ActivationChangeObserver::ActivationReason reason,
 534     aura::Window* gained_active,
 535     aura::Window* lost_active) {
 536   UpdateAutoHideStateNow();
 537 }
 538
 539 bool ShelfLayoutManager::IsHorizontalAlignment() const {
 540   return GetAlignment() == SHELF_ALIGNMENT_BOTTOM ||
 541          GetAlignment() == SHELF_ALIGNMENT_TOP;
 542 }
 543
 544 // static
 545 ShelfLayoutManager* ShelfLayoutManager::ForShelf(aura::Window* window) {
 546   ShelfWidget* shelf = RootWindowController::ForShelf(window)->shelf();
 547   return shelf ? shelf->shelf_layout_manager() : NULL;
 548 }
 549
 550 ////////////////////////////////////////////////////////////////////////////////
 551 // ShelfLayoutManager, private:
 552
 553 ShelfLayoutManager::TargetBounds::TargetBounds() : opacity(0.0f) {}
 554 ShelfLayoutManager::TargetBounds::~TargetBounds() {}
 555
 556 void ShelfLayoutManager::SetState(ShelfVisibilityState visibility_state) {
 557   if (!shelf_->GetNativeView())
 558     return;
 559
 560   State state;
 561   state.visibility_state = visibility_state;
 562   state.auto_hide_state = CalculateAutoHideState(visibility_state);
 563   state.window_state = workspace_controller_ ?
 564       workspace_controller_->GetWindowState() : WORKSPACE_WINDOW_STATE_DEFAULT;
 565   // Preserve the log in screen states.
 566   state.is_adding_user_screen = state_.is_adding_user_screen;
 567   state.is_screen_locked = state_.is_screen_locked;
 568
 569   // Force an update because gesture drags affect the shelf bounds and we
 570   // should animate back to the normal bounds at the end of a gesture.
 571   bool force_update =
 572       (gesture_drag_status_ == GESTURE_DRAG_CANCEL_IN_PROGRESS ||
 573        gesture_drag_status_ == GESTURE_DRAG_COMPLETE_IN_PROGRESS);
 574
 575   if (!force_update && state_.Equals(state))
 576     return;  // Nothing changed.
 577
 578   FOR_EACH_OBSERVER(ShelfLayoutManagerObserver, observers_,
 579                     WillChangeVisibilityState(visibility_state));
 580
 581   if (state.visibility_state == SHELF_AUTO_HIDE) {
 582     // When state is SHELF_AUTO_HIDE we need to track when the mouse is over the
 583     // shelf to unhide it. AutoHideEventFilter does that for us.
 584     if (!auto_hide_event_filter_)
 585       auto_hide_event_filter_.reset(new AutoHideEventFilter(this));
 586   } else {
 587     auto_hide_event_filter_.reset(NULL);
 588   }
 589
 590   StopAutoHideTimer();
 591
 592   State old_state = state_;
 593   state_ = state;
 594
 595   BackgroundAnimatorChangeType change_type = BACKGROUND_CHANGE_ANIMATE;
 596   bool delay_background_change = false;
 597
 598   // Do not animate the background when:
 599   // - Going from a hidden / auto hidden shelf in fullscreen to a visible shelf
 600   //   in maximized mode.
 601   // - Going from an auto hidden shelf in maximized mode to a visible shelf in
 602   //   maximized mode.
 603   if (state.visibility_state == SHELF_VISIBLE &&
 604       state.window_state == WORKSPACE_WINDOW_STATE_MAXIMIZED &&
 605       old_state.visibility_state != SHELF_VISIBLE) {
 606     change_type = BACKGROUND_CHANGE_IMMEDIATE;
 607   } else {
 608     // Delay the animation when the shelf was hidden, and has just been made
 609     // visible (e.g. using a gesture-drag).
 610     if (state.visibility_state == SHELF_VISIBLE &&
 611         old_state.visibility_state == SHELF_AUTO_HIDE &&
 612         old_state.auto_hide_state == SHELF_AUTO_HIDE_HIDDEN) {
 613       delay_background_change = true;
 614     }
 615   }
 616
 617   if (delay_background_change) {
 618     if (update_shelf_observer_)
 619       update_shelf_observer_->Detach();
 620     // UpdateShelfBackground deletes itself when the animation is done.
 621     update_shelf_observer_ = new UpdateShelfObserver(this);
 622   } else {
 623     UpdateShelfBackground(change_type);
 624   }
 625
 626   shelf_->SetDimsShelf(
 627       state.visibility_state == SHELF_VISIBLE &&
 628       state.window_state == WORKSPACE_WINDOW_STATE_MAXIMIZED);
 629
 630   TargetBounds target_bounds;
 631   CalculateTargetBounds(state_, &target_bounds);
 632   UpdateBoundsAndOpacity(target_bounds, true,
 633       delay_background_change ? update_shelf_observer_ : NULL);
 634
 635   // OnAutoHideStateChanged Should be emitted when:
 636   //  - firstly state changed to auto-hide from other state
 637   //  - or, auto_hide_state has changed
 638   if ((old_state.visibility_state != state_.visibility_state &&
 639        state_.visibility_state == SHELF_AUTO_HIDE) ||
 640       old_state.auto_hide_state != state_.auto_hide_state) {
 641     FOR_EACH_OBSERVER(ShelfLayoutManagerObserver, observers_,
 642                       OnAutoHideStateChanged(state_.auto_hide_state));
 643   }
 644 }
 645
 646 void ShelfLayoutManager::UpdateBoundsAndOpacity(
 647     const TargetBounds& target_bounds,
 648     bool animate,
 649     ui::ImplicitAnimationObserver* observer) {
 650   base::AutoReset<bool> auto_reset_updating_bounds(&updating_bounds_, true);
 651   {
 652     ui::ScopedLayerAnimationSettings shelf_animation_setter(
 653         GetLayer(shelf_)->GetAnimator());
 654     ui::ScopedLayerAnimationSettings status_animation_setter(
 655         GetLayer(shelf_->status_area_widget())->GetAnimator());
 656     if (animate) {
 657       int duration = duration_override_in_ms_ ? duration_override_in_ms_ :
 658                                                 kCrossFadeDurationMS;
 659       shelf_animation_setter.SetTransitionDuration(
 660           base::TimeDelta::FromMilliseconds(duration));
 661       shelf_animation_setter.SetTweenType(gfx::Tween::EASE_OUT);
 662       shelf_animation_setter.SetPreemptionStrategy(
 663           ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 664       status_animation_setter.SetTransitionDuration(
 665           base::TimeDelta::FromMilliseconds(duration));
 666       status_animation_setter.SetTweenType(gfx::Tween::EASE_OUT);
 667       status_animation_setter.SetPreemptionStrategy(
 668           ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 669     } else {
 670       StopAnimating();
 671       shelf_animation_setter.SetTransitionDuration(base::TimeDelta());
 672       status_animation_setter.SetTransitionDuration(base::TimeDelta());
 673     }
 674     if (observer)
 675       status_animation_setter.AddObserver(observer);
 676
 677     GetLayer(shelf_)->SetOpacity(target_bounds.opacity);
 678     shelf_->SetBounds(ScreenUtil::ConvertRectToScreen(
 679         shelf_->GetNativeView()->parent(),
 680         target_bounds.shelf_bounds_in_root));
 681
 682     GetLayer(shelf_->status_area_widget())->SetOpacity(
 683         target_bounds.status_opacity);
 684
 685     // Having a window which is visible but does not have an opacity is an
 686     // illegal state. We therefore hide the shelf here if required.
 687     if (!target_bounds.status_opacity)
 688       shelf_->status_area_widget()->Hide();
 689     // Setting visibility during an animation causes the visibility property to
 690     // animate. Override the animation settings to immediately set the
 691     // visibility property. Opacity will still animate.
 692
 693     // TODO(harrym): Once status area widget is a child view of shelf
 694     // this can be simplified.
 695     gfx::Rect status_bounds = target_bounds.status_bounds_in_shelf;
 696     status_bounds.set_x(status_bounds.x() +
 697                         target_bounds.shelf_bounds_in_root.x());
 698     status_bounds.set_y(status_bounds.y() +
 699                         target_bounds.shelf_bounds_in_root.y());
 700     shelf_->status_area_widget()->SetBounds(
 701         ScreenUtil::ConvertRectToScreen(
 702             shelf_->status_area_widget()->GetNativeView()->parent(),
 703             status_bounds));
 704     if (!state_.is_screen_locked) {
 705       gfx::Insets insets;
 706       // If user session is blocked (login to new user session or add user to
 707       // the existing session - multi-profile) then give 100% of work area only
 708       // if keyboard is not shown.
 709       if (!state_.is_adding_user_screen || !keyboard_bounds_.IsEmpty()) {
 710         insets = target_bounds.work_area_insets;
 711       }
 712       Shell::GetInstance()->SetDisplayWorkAreaInsets(root_window_, insets);
 713     }
 714   }
 715
 716   // Setting visibility during an animation causes the visibility property to
 717   // animate. Set the visibility property without an animation.
 718   if (target_bounds.status_opacity)
 719     shelf_->status_area_widget()->Show();
 720 }
 721
 722 void ShelfLayoutManager::StopAnimating() {
 723   GetLayer(shelf_)->GetAnimator()->StopAnimating();
 724   GetLayer(shelf_->status_area_widget())->GetAnimator()->StopAnimating();
 725 }
 726
 727 void ShelfLayoutManager::GetShelfSize(int* width, int* height) {
 728   *width = *height = 0;
 729   gfx::Size status_size(
 730       shelf_->status_area_widget()->GetWindowBoundsInScreen().size());
 731   if (IsHorizontalAlignment())
 732     *height = kShelfSize;
 733   else
 734     *width = kShelfSize;
 735 }
 736
 737 void ShelfLayoutManager::AdjustBoundsBasedOnAlignment(int inset,
 738                                                       gfx::Rect* bounds) const {
 739   bounds->Inset(SelectValueForShelfAlignment(
 740       gfx::Insets(0, 0, inset, 0),
 741       gfx::Insets(0, inset, 0, 0),
 742       gfx::Insets(0, 0, 0, inset),
 743       gfx::Insets(inset, 0, 0, 0)));
 744 }
 745
 746 void ShelfLayoutManager::CalculateTargetBounds(
 747     const State& state,
 748     TargetBounds* target_bounds) {
 749   gfx::Rect available_bounds =
 750       ScreenUtil::GetShelfDisplayBoundsInScreen(root_window_);
 751   available_bounds =
 752       ScreenUtil::ConvertRectFromScreen(root_window_, available_bounds);
 753
 754   gfx::Rect status_size(
 755       shelf_->status_area_widget()->GetWindowBoundsInScreen().size());
 756   int shelf_width = 0, shelf_height = 0;
 757   GetShelfSize(&shelf_width, &shelf_height);
 758   if (IsHorizontalAlignment())
 759     shelf_width = available_bounds.width();
 760   else
 761     shelf_height = available_bounds.height();
 762
 763   if (state.visibility_state == SHELF_AUTO_HIDE &&
 764       state.auto_hide_state == SHELF_AUTO_HIDE_HIDDEN) {
 765     // Auto-hidden shelf always starts with the default size. If a gesture-drag
 766     // is in progress, then the call to UpdateTargetBoundsForGesture() below
 767     // takes care of setting the height properly.
 768     if (IsHorizontalAlignment())
 769       shelf_height = kAutoHideSize;
 770     else
 771       shelf_width = kAutoHideSize;
 772   } else if (state.visibility_state == SHELF_HIDDEN ||
 773       (!keyboard_bounds_.IsEmpty() && !keyboard::IsKeyboardOverscrollEnabled()))
 774   {
 775     if (IsHorizontalAlignment())
 776       shelf_height = 0;
 777     else
 778       shelf_width = 0;
 779   }
 780
 781   int bottom_shelf_vertical_offset = available_bounds.bottom();
 782   if (keyboard_bounds_.IsEmpty())
 783     bottom_shelf_vertical_offset -= shelf_height;
 784   else
 785     bottom_shelf_vertical_offset -= keyboard_bounds_.height();
 786
 787   target_bounds->shelf_bounds_in_root = SelectValueForShelfAlignment(
 788       gfx::Rect(available_bounds.x(), bottom_shelf_vertical_offset,
 789                     available_bounds.width(), shelf_height),
 790       gfx::Rect(available_bounds.x(), available_bounds.y(),
 791                     shelf_width, available_bounds.height()),
 792       gfx::Rect(available_bounds.right() - shelf_width, available_bounds.y(),
 793                     shelf_width, available_bounds.height()),
 794       gfx::Rect(available_bounds.x(), available_bounds.y(),
 795                     available_bounds.width(), shelf_height));
 796
 797   if (IsHorizontalAlignment())
 798     status_size.set_height(kShelfSize);
 799   else
 800     status_size.set_width(kShelfSize);
 801
 802   target_bounds->status_bounds_in_shelf = SelectValueForShelfAlignment(
 803       gfx::Rect(base::i18n::IsRTL() ? 0 : shelf_width - status_size.width(),
 804                     0, status_size.width(), status_size.height()),
 805       gfx::Rect(shelf_width - status_size.width(),
 806                     shelf_height - status_size.height(), status_size.width(),
 807                     status_size.height()),
 808       gfx::Rect(0, shelf_height - status_size.height(),
 809                     status_size.width(), status_size.height()),
 810       gfx::Rect(base::i18n::IsRTL() ? 0 : shelf_width - status_size.width(),
 811                     shelf_height - status_size.height(),
 812                     status_size.width(), status_size.height()));
 813
 814   target_bounds->work_area_insets = SelectValueForShelfAlignment(
 815       gfx::Insets(0, 0, GetWorkAreaSize(state, shelf_height), 0),
 816       gfx::Insets(0, GetWorkAreaSize(state, shelf_width), 0, 0),
 817       gfx::Insets(0, 0, 0, GetWorkAreaSize(state, shelf_width)),
 818       gfx::Insets(GetWorkAreaSize(state, shelf_height), 0, 0, 0));
 819
 820   // TODO(varkha): The functionality of managing insets for display areas
 821   // should probably be pushed to a separate component. This would simplify or
 822   // remove entirely the dependency on keyboard and dock.
 823
 824   if (!keyboard_bounds_.IsEmpty() && !keyboard::IsKeyboardOverscrollEnabled()) {
 825     // Also push in the work area inset for the keyboard if it is visible.
 826     gfx::Insets keyboard_insets(0, 0, keyboard_bounds_.height(), 0);
 827     target_bounds->work_area_insets += keyboard_insets;
 828   }
 829
 830   // Also push in the work area inset for the dock if it is visible.
 831   if (!dock_bounds_.IsEmpty()) {
 832     gfx::Insets dock_insets(
 833         0, (dock_bounds_.x() > 0 ? 0 : dock_bounds_.width()),
 834         0, (dock_bounds_.x() > 0 ? dock_bounds_.width() : 0));
 835     target_bounds->work_area_insets += dock_insets;
 836   }
 837
 838   target_bounds->opacity =
 839       (gesture_drag_status_ == GESTURE_DRAG_IN_PROGRESS ||
 840        state.visibility_state == SHELF_VISIBLE ||
 841        state.visibility_state == SHELF_AUTO_HIDE) ? 1.0f : 0.0f;
 842   target_bounds->status_opacity =
 843       (state.visibility_state == SHELF_AUTO_HIDE &&
 844        state.auto_hide_state == SHELF_AUTO_HIDE_HIDDEN &&
 845        gesture_drag_status_ != GESTURE_DRAG_IN_PROGRESS) ?
 846       0.0f : target_bounds->opacity;
 847
 848   if (gesture_drag_status_ == GESTURE_DRAG_IN_PROGRESS)
 849     UpdateTargetBoundsForGesture(target_bounds);
 850
 851   // This needs to happen after calling UpdateTargetBoundsForGesture(), because
 852   // that can change the size of the shelf.
 853   target_bounds->shelf_bounds_in_shelf = SelectValueForShelfAlignment(
 854       gfx::Rect(0, 0,
 855                 shelf_width - status_size.width(),
 856                 target_bounds->shelf_bounds_in_root.height()),
 857       gfx::Rect(0, 0, target_bounds->shelf_bounds_in_root.width(),
 858                 shelf_height - status_size.height()),
 859       gfx::Rect(0, 0, target_bounds->shelf_bounds_in_root.width(),
 860                 shelf_height - status_size.height()),
 861       gfx::Rect(0, 0,
 862                 shelf_width - status_size.width(),
 863                 target_bounds->shelf_bounds_in_root.height()));
 864
 865   user_work_area_bounds_ = available_bounds;
 866   user_work_area_bounds_.Subtract(target_bounds->shelf_bounds_in_root);
 867   user_work_area_bounds_.Subtract(keyboard_bounds_);
 868 }
 869
 870 void ShelfLayoutManager::UpdateTargetBoundsForGesture(
 871     TargetBounds* target_bounds) const {
 872   CHECK_EQ(GESTURE_DRAG_IN_PROGRESS, gesture_drag_status_);
 873   bool horizontal = IsHorizontalAlignment();
 874   const gfx::Rect& available_bounds(root_window_->bounds());
 875   int resistance_free_region = 0;
 876
 877   if (gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_HIDDEN &&
 878       visibility_state() == SHELF_AUTO_HIDE &&
 879       auto_hide_state() != SHELF_AUTO_HIDE_SHOWN) {
 880     // If the shelf was hidden when the drag started (and the state hasn't
 881     // changed since then, e.g. because the tray-menu was shown because of the
 882     // drag), then allow the drag some resistance-free region at first to make
 883     // sure the shelf sticks with the finger until the shelf is visible.
 884     resistance_free_region = kShelfSize - kAutoHideSize;
 885   }
 886
 887   bool resist = SelectValueForShelfAlignment(
 888       gesture_drag_amount_ < -resistance_free_region,
 889       gesture_drag_amount_ > resistance_free_region,
 890       gesture_drag_amount_ < -resistance_free_region,
 891       gesture_drag_amount_ > resistance_free_region);
 892
 893   float translate = 0.f;
 894   if (resist) {
 895     float diff = fabsf(gesture_drag_amount_) - resistance_free_region;
 896     diff = std::min(diff, sqrtf(diff));
 897     if (gesture_drag_amount_ < 0)
 898       translate = -resistance_free_region - diff;
 899     else
 900       translate = resistance_free_region + diff;
 901   } else {
 902     translate = gesture_drag_amount_;
 903   }
 904
 905   if (horizontal) {
 906     // Move and size the shelf with the gesture.
 907     int shelf_height = target_bounds->shelf_bounds_in_root.height() - translate;
 908     shelf_height = std::max(shelf_height, kAutoHideSize);
 909     target_bounds->shelf_bounds_in_root.set_height(shelf_height);
 910     if (GetAlignment() == SHELF_ALIGNMENT_BOTTOM) {
 911       target_bounds->shelf_bounds_in_root.set_y(
 912           available_bounds.bottom() - shelf_height);
 913     }
 914
 915     target_bounds->status_bounds_in_shelf.set_y(0);
 916   } else {
 917     // Move and size the shelf with the gesture.
 918     int shelf_width = target_bounds->shelf_bounds_in_root.width();
 919     bool right_aligned = GetAlignment() == SHELF_ALIGNMENT_RIGHT;
 920     if (right_aligned)
 921       shelf_width -= translate;
 922     else
 923       shelf_width += translate;
 924     shelf_width = std::max(shelf_width, kAutoHideSize);
 925     target_bounds->shelf_bounds_in_root.set_width(shelf_width);
 926     if (right_aligned) {
 927       target_bounds->shelf_bounds_in_root.set_x(
 928           available_bounds.right() - shelf_width);
 929     }
 930
 931     if (right_aligned)
 932       target_bounds->status_bounds_in_shelf.set_x(0);
 933     else
 934       target_bounds->status_bounds_in_shelf.set_x(
 935           target_bounds->shelf_bounds_in_root.width() -
 936           kShelfSize);
 937   }
 938 }
 939
 940 void ShelfLayoutManager::UpdateShelfBackground(
 941     BackgroundAnimatorChangeType type) {
 942   const ShelfBackgroundType background_type(GetShelfBackgroundType());
 943   shelf_->SetPaintsBackground(background_type, type);
 944   FOR_EACH_OBSERVER(ShelfLayoutManagerObserver, observers_,
 945                     OnBackgroundUpdated(background_type, type));
 946 }
 947
 948 ShelfBackgroundType ShelfLayoutManager::GetShelfBackgroundType() const {
 949   if (state_.visibility_state != SHELF_AUTO_HIDE &&
 950       state_.window_state == WORKSPACE_WINDOW_STATE_MAXIMIZED) {
 951     return SHELF_BACKGROUND_MAXIMIZED;
 952   }
 953
 954   if (gesture_drag_status_ == GESTURE_DRAG_IN_PROGRESS ||
 955       (!state_.is_screen_locked && !state_.is_adding_user_screen &&
 956        window_overlaps_shelf_) ||
 957       (state_.visibility_state == SHELF_AUTO_HIDE)) {
 958     return SHELF_BACKGROUND_OVERLAP;
 959   }
 960
 961   return SHELF_BACKGROUND_DEFAULT;
 962 }
 963
 964 void ShelfLayoutManager::UpdateAutoHideStateNow() {
 965   SetState(state_.visibility_state);
 966
 967   // If the state did not change, the auto hide timer may still be running.
 968   StopAutoHideTimer();
 969 }
 970
 971 void ShelfLayoutManager::StopAutoHideTimer() {
 972   auto_hide_timer_.Stop();
 973   mouse_over_shelf_when_auto_hide_timer_started_ = false;
 974 }
 975
 976 gfx::Rect ShelfLayoutManager::GetAutoHideShowShelfRegionInScreen() const {
 977   gfx::Rect shelf_bounds_in_screen = shelf_->GetWindowBoundsInScreen();
 978   gfx::Vector2d offset = SelectValueForShelfAlignment(
 979       gfx::Vector2d(0, shelf_bounds_in_screen.height()),
 980       gfx::Vector2d(-kMaxAutoHideShowShelfRegionSize, 0),
 981       gfx::Vector2d(shelf_bounds_in_screen.width(), 0),
 982       gfx::Vector2d(0, -kMaxAutoHideShowShelfRegionSize));
 983
 984   gfx::Rect show_shelf_region_in_screen = shelf_bounds_in_screen;
 985   show_shelf_region_in_screen += offset;
 986   if (IsHorizontalAlignment())
 987     show_shelf_region_in_screen.set_height(kMaxAutoHideShowShelfRegionSize);
 988   else
 989     show_shelf_region_in_screen.set_width(kMaxAutoHideShowShelfRegionSize);
 990
 991   // TODO: Figure out if we need any special handling when the keyboard is
 992   // visible.
 993   return show_shelf_region_in_screen;
 994 }
 995
 996 ShelfAutoHideState ShelfLayoutManager::CalculateAutoHideState(
 997     ShelfVisibilityState visibility_state) const {
 998   if (visibility_state != SHELF_AUTO_HIDE || !shelf_)
 999     return SHELF_AUTO_HIDE_HIDDEN;
1000
1001   Shell* shell = Shell::GetInstance();
1002   // Unhide the shelf only on the active screen when the AppList is shown
1003   // (crbug.com/312445).
1004   if (shell->GetAppListTargetVisibility()) {
1005     aura::Window* active_window = wm::GetActiveWindow();
1006     aura::Window* shelf_window = shelf_->GetNativeWindow();
1007     if (active_window && shelf_window &&
1008         active_window->GetRootWindow() == shelf_window->GetRootWindow()) {
1009       return SHELF_AUTO_HIDE_SHOWN;
1010     }
1011   }
1012
1013   if (shelf_->status_area_widget() &&
1014       shelf_->status_area_widget()->ShouldShowShelf())
1015     return SHELF_AUTO_HIDE_SHOWN;
1016
1017   if (shelf_->shelf() && shelf_->shelf()->IsShowingMenu())
1018     return SHELF_AUTO_HIDE_SHOWN;
1019
1020   if (shelf_->shelf() && shelf_->shelf()->IsShowingOverflowBubble())
1021     return SHELF_AUTO_HIDE_SHOWN;
1022
1023   if (shelf_->IsActive() ||
1024       (shelf_->status_area_widget() &&
1025        shelf_->status_area_widget()->IsActive()))
1026     return SHELF_AUTO_HIDE_SHOWN;
1027
1028   const std::vector<aura::Window*> windows =
1029       shell->mru_window_tracker()->BuildWindowListIgnoreModal();
1030
1031   // Process the window list and check if there are any visible windows.
1032   bool visible_window = false;
1033   for (size_t i = 0; i < windows.size(); ++i) {
1034     if (windows[i] && windows[i]->IsVisible() &&
1035         !wm::GetWindowState(windows[i])->IsMinimized() &&
1036         root_window_ == windows[i]->GetRootWindow()) {
1037       visible_window = true;
1038       break;
1039     }
1040   }
1041   // If there are no visible windows do not hide the shelf.
1042   if (!visible_window)
1043     return SHELF_AUTO_HIDE_SHOWN;
1044
1045   if (gesture_drag_status_ == GESTURE_DRAG_COMPLETE_IN_PROGRESS)
1046     return gesture_drag_auto_hide_state_;
1047
1048   // Don't show if the user is dragging the mouse.
1049   if (auto_hide_event_filter_.get() && auto_hide_event_filter_->in_mouse_drag())
1050     return SHELF_AUTO_HIDE_HIDDEN;
1051
1052   // Ignore the mouse position if mouse events are disabled.
1053   aura::client::CursorClient* cursor_client = aura::client::GetCursorClient(
1054       shelf_->GetNativeWindow()->GetRootWindow());
1055   if (!cursor_client->IsMouseEventsEnabled())
1056     return SHELF_AUTO_HIDE_HIDDEN;
1057
1058   gfx::Rect shelf_region = shelf_->GetWindowBoundsInScreen();
1059   if (shelf_->status_area_widget() &&
1060       shelf_->status_area_widget()->IsMessageBubbleShown() &&
1061       IsVisible()) {
1062     // Increase the the hit test area to prevent the shelf from disappearing
1063     // when the mouse is over the bubble gap.
1064     ShelfAlignment alignment = GetAlignment();
1065     shelf_region.Inset(alignment == SHELF_ALIGNMENT_RIGHT ?
1066                            -kNotificationBubbleGapHeight : 0,
1067                        alignment == SHELF_ALIGNMENT_BOTTOM ?
1068                            -kNotificationBubbleGapHeight : 0,
1069                        alignment == SHELF_ALIGNMENT_LEFT ?
1070                            -kNotificationBubbleGapHeight : 0,
1071                        alignment == SHELF_ALIGNMENT_TOP ?
1072                            -kNotificationBubbleGapHeight : 0);
1073   }
1074
1075   gfx::Point cursor_position_in_screen =
1076       Shell::GetScreen()->GetCursorScreenPoint();
1077   if (shelf_region.Contains(cursor_position_in_screen))
1078     return SHELF_AUTO_HIDE_SHOWN;
1079
1080   // When the shelf is auto hidden and the shelf is on the boundary between two
1081   // displays, it is hard to trigger showing the shelf. For instance, if a
1082   // user's primary display is left of their secondary display, it is hard to
1083   // unautohide a left aligned shelf on the secondary display.
1084   // It is hard because:
1085   // - It is hard to stop the cursor in the shelf "light bar" and not overshoot.
1086   // - The cursor is warped to the other display if the cursor gets to the edge
1087   //   of the display.
1088   // Show the shelf if the cursor started on the shelf and the user overshot the
1089   // shelf slightly to make it easier to show the shelf in this situation. We
1090   // do not check |auto_hide_timer_|.IsRunning() because it returns false when
1091   // the timer's task is running.
1092   if ((state_.auto_hide_state == SHELF_AUTO_HIDE_SHOWN ||
1093        mouse_over_shelf_when_auto_hide_timer_started_) &&
1094       GetAutoHideShowShelfRegionInScreen().Contains(
1095           cursor_position_in_screen)) {
1096     return SHELF_AUTO_HIDE_SHOWN;
1097   }
1098
1099   return SHELF_AUTO_HIDE_HIDDEN;
1100 }
1101
1102 bool ShelfLayoutManager::IsShelfWindow(aura::Window* window) {
1103   if (!window)
1104     return false;
1105   return (shelf_ && shelf_->GetNativeWindow()->Contains(window)) ||
1106       (shelf_->status_area_widget() &&
1107        shelf_->status_area_widget()->GetNativeWindow()->Contains(window));
1108 }
1109
1110 int ShelfLayoutManager::GetWorkAreaSize(const State& state, int size) const {
1111   if (state.visibility_state == SHELF_VISIBLE)
1112     return size;
1113   if (state.visibility_state == SHELF_AUTO_HIDE)
1114     return kAutoHideSize;
1115   return 0;
1116 }
1117
1118 void ShelfLayoutManager::OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) {
1119   bool keyboard_is_about_to_hide = false;
1120   if (new_bounds.IsEmpty() && !keyboard_bounds_.IsEmpty())
1121     keyboard_is_about_to_hide = true;
1122
1123   keyboard_bounds_ = new_bounds;
1124   OnWindowResized();
1125
1126   SessionStateDelegate* session_state_delegate =
1127       Shell::GetInstance()->session_state_delegate();
1128
1129   // On login screen if keyboard has been just hidden, update bounds just once
1130   // but ignore target_bounds.work_area_insets since shelf overlaps with login
1131   // window.
1132   if (session_state_delegate->IsUserSessionBlocked() &&
1133       keyboard_is_about_to_hide) {
1134     Shell::GetInstance()->SetDisplayWorkAreaInsets(root_window_, gfx::Insets());
1135   }
1136 }
1137
1138 void ShelfLayoutManager::OnDockBoundsChanging(
1139     const gfx::Rect& dock_bounds,
1140     DockedWindowLayoutManagerObserver::Reason reason) {
1141   // Skip shelf layout in case docked notification originates from this class.
1142   if (reason == DISPLAY_INSETS_CHANGED)
1143     return;
1144   if (dock_bounds_ != dock_bounds) {
1145     dock_bounds_ = dock_bounds;
1146     OnWindowResized();
1147     UpdateVisibilityState();
1148     UpdateShelfBackground(BACKGROUND_CHANGE_ANIMATE);
1149   }
1150 }
1151
1152 void ShelfLayoutManager::OnLockStateEvent(LockStateObserver::EventType event) {
1153   if (event == EVENT_LOCK_ANIMATION_STARTED) {
1154     // Enter the screen locked state and update the visibility to avoid an odd
1155     // animation when transitioning the orientation from L/R to bottom.
1156     state_.is_screen_locked = true;
1157     UpdateShelfVisibilityAfterLoginUIChange();
1158   }
1159 }
1160
1161 void ShelfLayoutManager::SessionStateChanged(
1162     SessionStateDelegate::SessionState state) {
1163   // Check transition changes to/from the add user to session and change the
1164   // shelf alignment accordingly
1165   bool add_user = state == SessionStateDelegate::SESSION_STATE_LOGIN_SECONDARY;
1166   if (add_user != state_.is_adding_user_screen) {
1167     state_.is_adding_user_screen = add_user;
1168     UpdateShelfVisibilityAfterLoginUIChange();
1169     return;
1170   }
1171   TargetBounds target_bounds;
1172   CalculateTargetBounds(state_, &target_bounds);
1173   UpdateBoundsAndOpacity(target_bounds, true, NULL);
1174   UpdateVisibilityState();
1175 }
1176
1177 void ShelfLayoutManager::UpdateShelfVisibilityAfterLoginUIChange() {
1178   shelf_->SetAlignment(GetAlignment());
1179   UpdateVisibilityState();
1180   LayoutShelf();
1181 }
1182
1183 bool ShelfLayoutManager::IsAlignmentLocked() const {
1184   if (state_.is_screen_locked)
1185     return true;
1186   // The session state becomes active at the start of transitioning to a user
1187   // session, however the session is considered blocked until the full UI is
1188   // ready. Exit early to allow for proper layout.
1189   SessionStateDelegate* session_state_delegate =
1190       Shell::GetInstance()->session_state_delegate();
1191   if (session_state_delegate->GetSessionState() ==
1192       SessionStateDelegate::SESSION_STATE_ACTIVE) {
1193     return false;
1194   }
1195   if (session_state_delegate->IsUserSessionBlocked() ||
1196       state_.is_adding_user_screen) {
1197     return true;
1198   }
1199   return false;
1200 }
1201
1202 }  // namespace ash