ash/wm/always_on_top_controller.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/wm/always_on_top_controller.h"
   6
   7 #include "ash/shell.h"
   8 #include "ash/shell_window_ids.h"
   9 #include "ui/aura/client/aura_constants.h"
  10 #include "ui/aura/window.h"
  11
  12 namespace ash {
  13
  14 AlwaysOnTopController::AlwaysOnTopController()
  15     : always_on_top_container_(NULL) {
  16 }
  17
  18 AlwaysOnTopController::~AlwaysOnTopController() {
  19   if (always_on_top_container_)
  20     always_on_top_container_->RemoveObserver(this);
  21 }
  22
  23 void AlwaysOnTopController::SetAlwaysOnTopContainer(
  24     aura::Window* always_on_top_container) {
  25   // Container should be empty.
  26   DCHECK(always_on_top_container->children().empty());
  27
  28   // We are not handling any containers yet.
  29   DCHECK(always_on_top_container_ == NULL);
  30
  31   always_on_top_container_ = always_on_top_container;
  32   always_on_top_container_->AddObserver(this);
  33 }
  34
  35 aura::Window* AlwaysOnTopController::GetContainer(aura::Window* window) const {
  36   DCHECK(always_on_top_container_);
  37   if (window->GetProperty(aura::client::kAlwaysOnTopKey))
  38     return always_on_top_container_;
  39   return Shell::GetContainer(always_on_top_container_->GetRootWindow(),
  40                              kShellWindowId_DefaultContainer);
  41 }
  42
  43 void AlwaysOnTopController::OnWindowAdded(aura::Window* child) {
  44   // Observe direct child of the containers.
  45   if (child->parent() == always_on_top_container_)
  46     child->AddObserver(this);
  47 }
  48
  49 void AlwaysOnTopController::OnWillRemoveWindow(aura::Window* child) {
  50   child->RemoveObserver(this);
  51 }
  52
  53 void AlwaysOnTopController::OnWindowPropertyChanged(aura::Window* window,
  54                                                     const void* key,
  55                                                     intptr_t old) {
  56   if (key == aura::client::kAlwaysOnTopKey) {
  57     DCHECK(window->type() == ui::wm::WINDOW_TYPE_NORMAL ||
  58            window->type() == ui::wm::WINDOW_TYPE_POPUP);
  59     aura::Window* container = GetContainer(window);
  60     if (window->parent() != container)
  61       container->AddChild(window);
  62   }
  63 }
  64
  65 void AlwaysOnTopController::OnWindowDestroyed(aura::Window* window) {
  66   if (window == always_on_top_container_)
  67     always_on_top_container_ = NULL;
  68 }
  69
  70 }  // namespace ash