ash: Start/stop observing KeyboardController via ShellObserver

ash/common/wm/workspace/workspace_layout_manager.cc

 // 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.
 
 #include "ash/common/wm/workspace/workspace_layout_manager.h"
 
 #include <algorithm>
 
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shelf/wm_shelf.h"
@@ skipping 22 matching lines @@
 #include "ui/wm/public/activation_client.h"
 
 namespace ash {
 
 WorkspaceLayoutManager::WorkspaceLayoutManager(WmWindow* window)
     : window_(window),
       root_window_(window->GetRootWindow()),
       root_window_controller_(root_window_->GetRootWindowController()),
       shell_(window_->GetShell()),
       work_area_in_parent_(wm::GetDisplayWorkAreaBoundsInParent(window_)),
-      is_fullscreen_(wm::GetWindowForFullscreenMode(window) != nullptr) {
+      is_fullscreen_(wm::GetWindowForFullscreenMode(window) != nullptr),
+      keyboard_observer_(this) {
   Shell::GetInstance()->AddShellObserver(this);
   Shell::GetInstance()->activation_client()->AddObserver(this);
   root_window_->aura_window()->AddObserver(this);
   display::Screen::GetScreen()->AddObserver(this);
   DCHECK(window->aura_window()->GetProperty(kSnapChildrenToPixelBoundary));
 }
 
 WorkspaceLayoutManager::~WorkspaceLayoutManager() {
   if (root_window_)
     root_window_->aura_window()->RemoveObserver(this);
@@ skipping 117 matching lines @@
     }
   } else if (window_state->HasRestoreBounds()) {
     // Keyboard hidden, restore original bounds if they exist. If the user has
     // resized or dragged the window in the meantime, WorkspaceWindowResizer
     // will have cleared the restore bounds and this code will not accidentally
     // override user intent.
     window_state->SetAndClearRestoreBounds();
   }
 }
 
-void WorkspaceLayoutManager::OnKeyboardClosed() {}
+void WorkspaceLayoutManager::OnKeyboardClosed() {
+  keyboard_observer_.RemoveAll();
+}
 
 //////////////////////////////////////////////////////////////////////////////
 // WorkspaceLayoutManager, aura::WindowObserver implementation:
 
 void WorkspaceLayoutManager::OnWindowHierarchyChanged(
     const HierarchyChangeParams& params) {
   if (!wm::GetWindowState(params.target)->IsActive())
     return;
   // If the window is already tracked by the workspace this update would be
   // redundant as the fullscreen and shelf state would have been handled in
@@ skipping 128 matching lines @@
     // On exiting from pinned mode, if the workspace is still in fullscreen
     // mode, then this event does not trigger the restoring yet. On exiting
     // from fullscreen, the temporarily disabled always-on-top property will be
     // restored.
     return;
   }
 
   UpdateAlwaysOnTop(WmShell::Get()->IsPinned() ? pinned_window : nullptr);
 }
 
+void WorkspaceLayoutManager::OnVirtualKeyboardStateChanged(
+    bool activated,
+    WmWindow* root_window) {
+  if (root_window != root_window_)

[sky, 2017/03/14 03:23:50]

As this code exists in a handful of places, WDYT of a function like:

UpdateKeyboardObserverFromStateChanged(bool activated,
WmWindow* keyboard_root_window,
WmWindow* root_window,
keyboard_observer).

All the overrides would have the single call to
UpdateKeyboardObserverFromStateChanged, eg:
UpdateKeyboardObserverFromStated(activated, root_window, root_window_,
&keyboard_observer);

And UpdateKeyboardObserverFromStateChanged would go in the file
keyboard_observer_register?

[xiyuan, 2017/03/14 21:25:55]

Good idea. Done.

+    return;
+
+  keyboard::KeyboardController* const keyboard_controller =
+      keyboard::KeyboardController::GetInstance();
+  if (activated && !keyboard_observer_.IsObserving(keyboard_controller)) {
+    keyboard_observer_.Add(keyboard_controller);
+  } else if (!activated &&
+             keyboard_observer_.IsObserving(keyboard_controller)) {
+    keyboard_observer_.Remove(keyboard_controller);
+  }
+}
+
 //////////////////////////////////////////////////////////////////////////////
 // WorkspaceLayoutManager, private:
 
 void WorkspaceLayoutManager::AdjustAllWindowsBoundsForWorkAreaChange(
     const wm::WMEvent* event) {
   DCHECK(event->type() == wm::WM_EVENT_DISPLAY_BOUNDS_CHANGED ||
          event->type() == wm::WM_EVENT_WORKAREA_BOUNDS_CHANGED);
 
   work_area_in_parent_ = wm::GetDisplayWorkAreaBoundsInParent(window_);
 
@@ skipping 43 matching lines @@
   for (auto* window : windows) {
     wm::WindowState* window_state = window->GetWindowState();
     if (window_on_top)
       window_state->DisableAlwaysOnTop(window_on_top);
     else
       window_state->RestoreAlwaysOnTop();
   }
 }
 
 }  // namespace ash