1 // Copyright 2013 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/mru_window_tracker.h" 6 7 #include <algorithm> 8 9 #include "ash/session_state_delegate.h" 10 #include "ash/shell.h" 11 #include "ash/shell_window_ids.h" 12 #include "ash/wm/window_cycle_list.h" 13 #include "ash/wm/window_util.h" 14 #include "ash/wm/workspace_controller.h" 15 #include "ui/aura/client/activation_client.h" 16 #include "ui/aura/root_window.h" 17 #include "ui/events/event.h" 18 #include "ui/events/event_handler.h" 19 20 namespace ash { 21 22 namespace { 23 24 // Adds the windows that can be cycled through for the specified window id to 25 // |windows|. 26 void AddTrackedWindows(aura::Window* root, 27 int container_id, 28 MruWindowTracker::WindowList* windows) { 29 aura::Window* container = Shell::GetContainer(root, container_id); 30 const MruWindowTracker::WindowList& children(container->children()); 31 windows->insert(windows->end(), children.begin(), children.end()); 32 } 33 34 // Returns true if |window| is a container whose windows can be cycled to. 35 bool IsSwitchableContainer(aura::Window* window) { 36 if (!window) 37 return false; 38 for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i) { 39 if (window->id() == kSwitchableWindowContainerIds[i]) 40 return true; 41 } 42 return false; 43 } 44 45 // Returns whether |w1| should be considered less recently used than |w2|. This 46 // is used for a stable sort to move minimized windows to the LRU end of the 47 // list. 48 bool CompareWindowState(aura::Window* w1, aura::Window* w2) { 49 return ash::wm::IsWindowMinimized(w1) && !ash::wm::IsWindowMinimized(w2); 50 } 51 52 // Returns a list of windows ordered by their stacking order. 53 // If |mru_windows| is passed, these windows are moved to the front of the list. 54 // If |top_most_at_end|, the list is returned in descending (bottom-most / least 55 // recently used) order. 56 MruWindowTracker::WindowList BuildWindowListInternal( 57 const std::list<aura::Window*>* mru_windows, 58 bool top_most_at_end) { 59 MruWindowTracker::WindowList windows; 60 aura::Window::Windows root_windows = Shell::GetAllRootWindows(); 61 62 aura::Window* active_root = Shell::GetTargetRootWindow(); 63 for (aura::Window::Windows::const_iterator iter = root_windows.begin(); 64 iter != root_windows.end(); ++iter) { 65 if (*iter == active_root) 66 continue; 67 for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i) 68 AddTrackedWindows(*iter, kSwitchableWindowContainerIds[i], &windows); 69 } 70 71 // Add windows in the active root windows last so that the topmost window 72 // in the active root window becomes the front of the list. 73 for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i) 74 AddTrackedWindows(active_root, kSwitchableWindowContainerIds[i], &windows); 75 76 // Removes unfocusable windows. 77 MruWindowTracker::WindowList::iterator last = 78 std::remove_if( 79 windows.begin(), 80 windows.end(), 81 std::not1(std::ptr_fun(ash::wm::CanActivateWindow))); 82 windows.erase(last, windows.end()); 83 84 // Put the windows in the mru_windows list at the head, if it's available. 85 if (mru_windows) { 86 // Iterate through the list backwards, so that we can move each window to 87 // the front of the windows list as we find them. 88 for (std::list<aura::Window*>::const_reverse_iterator ix = 89 mru_windows->rbegin(); 90 ix != mru_windows->rend(); ++ix) { 91 // Exclude windows in non-switchable containers and those which cannot 92 // be activated. 93 if (!IsSwitchableContainer((*ix)->parent()) || 94 !ash::wm::CanActivateWindow(*ix)) { 95 continue; 96 } 97 98 MruWindowTracker::WindowList::iterator window = 99 std::find(windows.begin(), windows.end(), *ix); 100 if (window != windows.end()) { 101 windows.erase(window); 102 windows.push_back(*ix); 103 } 104 } 105 } 106 107 // Move minimized windows to the beginning (LRU end) of the list. 108 std::stable_sort(windows.begin(), windows.end(), CompareWindowState); 109 110 // Window cycling expects the topmost window at the front of the list. 111 if (!top_most_at_end) 112 std::reverse(windows.begin(), windows.end()); 113 114 return windows; 115 } 116 117 } // namespace 118 119 const int kSwitchableWindowContainerIds[] = { 120 internal::kShellWindowId_DefaultContainer, 121 internal::kShellWindowId_AlwaysOnTopContainer, 122 internal::kShellWindowId_PanelContainer 123 }; 124 125 const size_t kSwitchableWindowContainerIdsLength = 126 arraysize(kSwitchableWindowContainerIds); 127 128 ////////////////////////////////////////////////////////////////////////////// 129 // MruWindowTracker, public: 130 131 MruWindowTracker::MruWindowTracker( 132 aura::client::ActivationClient* activation_client) 133 : activation_client_(activation_client), 134 ignore_window_activations_(false) { 135 activation_client_->AddObserver(this); 136 } 137 138 MruWindowTracker::~MruWindowTracker() { 139 for (std::list<aura::Window*>::iterator iter = mru_windows_.begin(); 140 iter != mru_windows_.end(); ++iter) { 141 (*iter)->RemoveObserver(this); 142 } 143 144 activation_client_->RemoveObserver(this); 145 } 146 147 // static 148 MruWindowTracker::WindowList MruWindowTracker::BuildWindowList( 149 bool top_most_at_end) { 150 return BuildWindowListInternal(NULL, top_most_at_end); 151 } 152 153 MruWindowTracker::WindowList MruWindowTracker::BuildMruWindowList() { 154 return BuildWindowListInternal(&mru_windows_, false); 155 } 156 157 void MruWindowTracker::SetIgnoreActivations(bool ignore) { 158 ignore_window_activations_ = ignore; 159 160 // If no longer ignoring window activations, move currently active window 161 // to front. 162 if (!ignore) 163 SetActiveWindow(wm::GetActiveWindow()); 164 } 165 166 ////////////////////////////////////////////////////////////////////////////// 167 // MruWindowTracker, private: 168 169 void MruWindowTracker::SetActiveWindow(aura::Window* active_window) { 170 if (!active_window) 171 return; 172 173 std::list<aura::Window*>::iterator iter = 174 std::find(mru_windows_.begin(), mru_windows_.end(), active_window); 175 // Observe all newly tracked windows. 176 if (iter == mru_windows_.end()) 177 active_window->AddObserver(this); 178 else 179 mru_windows_.erase(iter); 180 // TODO(flackr): Remove this check if this doesn't fire for a while. This 181 // should verify that all tracked windows start with a layer, see 182 // http://crbug.com/291354. 183 CHECK(active_window->layer()); 184 mru_windows_.push_front(active_window); 185 } 186 187 void MruWindowTracker::OnWindowActivated(aura::Window* gained_active, 188 aura::Window* lost_active) { 189 if (!ignore_window_activations_) 190 SetActiveWindow(gained_active); 191 } 192 193 void MruWindowTracker::OnWindowDestroying(aura::Window* window) { 194 mru_windows_.remove(window); 195 window->RemoveObserver(this); 196 } 197 198 } // namespace ash 199