ui/wm/core/focus_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 "ui/wm/core/focus_controller.h"
   6
   7 #include "base/auto_reset.h"
   8 #include "ui/aura/client/aura_constants.h"
   9 #include "ui/aura/client/capture_client.h"
  10 #include "ui/aura/client/focus_change_observer.h"
  11 #include "ui/aura/env.h"
  12 #include "ui/aura/window_tracker.h"
  13 #include "ui/events/event.h"
  14 #include "ui/wm/core/focus_rules.h"
  15 #include "ui/wm/core/window_util.h"
  16 #include "ui/wm/public/activation_change_observer.h"
  17
  18 namespace wm {
  19 namespace {
  20
  21 // When a modal window is activated, we bring its entire transient parent chain
  22 // to the front. This function must be called before the modal transient is
  23 // stacked at the top to ensure correct stacking order.
  24 void StackTransientParentsBelowModalWindow(aura::Window* window) {
  25   if (window->GetProperty(aura::client::kModalKey) != ui::MODAL_TYPE_WINDOW)
  26     return;
  27
  28   aura::Window* transient_parent = wm::GetTransientParent(window);
  29   while (transient_parent) {
  30     transient_parent->parent()->StackChildAtTop(transient_parent);
  31     transient_parent = wm::GetTransientParent(transient_parent);
  32   }
  33 }
  34
  35 }  // namespace
  36
  37 ////////////////////////////////////////////////////////////////////////////////
  38 // FocusController, public:
  39
  40 FocusController::FocusController(FocusRules* rules)
  41     : active_window_(NULL),
  42       focused_window_(NULL),
  43       updating_focus_(false),
  44       updating_activation_(false),
  45       rules_(rules),
  46       observer_manager_(this) {
  47   DCHECK(rules);
  48 }
  49
  50 FocusController::~FocusController() {
  51 }
  52
  53 ////////////////////////////////////////////////////////////////////////////////
  54 // FocusController, aura::client::ActivationClient implementation:
  55
  56 void FocusController::AddObserver(
  57     aura::client::ActivationChangeObserver* observer) {
  58   activation_observers_.AddObserver(observer);
  59 }
  60
  61 void FocusController::RemoveObserver(
  62     aura::client::ActivationChangeObserver* observer) {
  63   activation_observers_.RemoveObserver(observer);
  64 }
  65
  66 void FocusController::ActivateWindow(aura::Window* window) {
  67   FocusWindow(window);
  68 }
  69
  70 void FocusController::DeactivateWindow(aura::Window* window) {
  71   if (window)
  72     FocusWindow(rules_->GetNextActivatableWindow(window));
  73 }
  74
  75 aura::Window* FocusController::GetActiveWindow() {
  76   return active_window_;
  77 }
  78
  79 aura::Window* FocusController::GetActivatableWindow(aura::Window* window) {
  80   return rules_->GetActivatableWindow(window);
  81 }
  82
  83 aura::Window* FocusController::GetToplevelWindow(aura::Window* window) {
  84   return rules_->GetToplevelWindow(window);
  85 }
  86
  87 bool FocusController::CanActivateWindow(aura::Window* window) const {
  88   return rules_->CanActivateWindow(window);
  89 }
  90
  91 ////////////////////////////////////////////////////////////////////////////////
  92 // FocusController, aura::client::FocusClient implementation:
  93
  94 void FocusController::AddObserver(
  95     aura::client::FocusChangeObserver* observer) {
  96   focus_observers_.AddObserver(observer);
  97 }
  98
  99 void FocusController::RemoveObserver(
 100     aura::client::FocusChangeObserver* observer) {
 101   focus_observers_.RemoveObserver(observer);
 102 }
 103
 104 void FocusController::FocusWindow(aura::Window* window) {
 105   FocusAndActivateWindow(aura::client::ActivationChangeObserver::
 106                              ActivationReason::ACTIVATION_CLIENT,
 107                          window);
 108 }
 109
 110 void FocusController::ResetFocusWithinActiveWindow(aura::Window* window) {
 111   DCHECK(window);
 112   if (!active_window_)
 113     return;
 114   if (!active_window_->Contains(window))
 115     return;
 116   SetFocusedWindow(window);
 117 }
 118
 119 aura::Window* FocusController::GetFocusedWindow() {
 120   return focused_window_;
 121 }
 122
 123 ////////////////////////////////////////////////////////////////////////////////
 124 // FocusController, ui::EventHandler implementation:
 125 void FocusController::OnKeyEvent(ui::KeyEvent* event) {
 126 }
 127
 128 void FocusController::OnMouseEvent(ui::MouseEvent* event) {
 129   if (event->type() == ui::ET_MOUSE_PRESSED && !event->handled())
 130     WindowFocusedFromInputEvent(static_cast<aura::Window*>(event->target()));
 131 }
 132
 133 void FocusController::OnScrollEvent(ui::ScrollEvent* event) {
 134 }
 135
 136 void FocusController::OnTouchEvent(ui::TouchEvent* event) {
 137 }
 138
 139 void FocusController::OnGestureEvent(ui::GestureEvent* event) {
 140   if (event->type() == ui::ET_GESTURE_BEGIN &&
 141       event->details().touch_points() == 1 &&
 142       !event->handled()) {
 143     WindowFocusedFromInputEvent(static_cast<aura::Window*>(event->target()));
 144   }
 145 }
 146
 147 ////////////////////////////////////////////////////////////////////////////////
 148 // FocusController, aura::WindowObserver implementation:
 149
 150 void FocusController::OnWindowVisibilityChanged(aura::Window* window,
 151                                                 bool visible) {
 152   if (!visible)
 153     WindowLostFocusFromDispositionChange(window, window->parent());
 154 }
 155
 156 void FocusController::OnWindowDestroying(aura::Window* window) {
 157   // A window's modality state will interfere with focus restoration during its
 158   // destruction.
 159   window->ClearProperty(aura::client::kModalKey);
 160   WindowLostFocusFromDispositionChange(window, window->parent());
 161 }
 162
 163 void FocusController::OnWindowHierarchyChanging(
 164     const HierarchyChangeParams& params) {
 165   if (params.receiver == active_window_ &&
 166       params.target->Contains(params.receiver) && (!params.new_parent ||
 167       aura::client::GetFocusClient(params.new_parent) !=
 168           aura::client::GetFocusClient(params.receiver))) {
 169     WindowLostFocusFromDispositionChange(params.receiver, params.old_parent);
 170   }
 171 }
 172
 173 void FocusController::OnWindowHierarchyChanged(
 174     const HierarchyChangeParams& params) {
 175   if (params.receiver == focused_window_ &&
 176       params.target->Contains(params.receiver) && (!params.new_parent ||
 177       aura::client::GetFocusClient(params.new_parent) !=
 178           aura::client::GetFocusClient(params.receiver))) {
 179     WindowLostFocusFromDispositionChange(params.receiver, params.old_parent);
 180   }
 181 }
 182
 183 ////////////////////////////////////////////////////////////////////////////////
 184 // FocusController, private:
 185
 186 void FocusController::FocusAndActivateWindow(
 187     aura::client::ActivationChangeObserver::ActivationReason reason,
 188     aura::Window* window) {
 189   if (window &&
 190       (window->Contains(focused_window_) || window->Contains(active_window_))) {
 191     return;
 192   }
 193
 194   // Focusing a window also activates its containing activatable window. Note
 195   // that the rules could redirect activation activation and/or focus.
 196   aura::Window* focusable = rules_->GetFocusableWindow(window);
 197   aura::Window* activatable =
 198       focusable ? rules_->GetActivatableWindow(focusable) : NULL;
 199
 200   // We need valid focusable/activatable windows in the event we're not clearing
 201   // focus. "Clearing focus" is inferred by whether or not |window| passed to
 202   // this function is non-NULL.
 203   if (window && (!focusable || !activatable))
 204     return;
 205   DCHECK((focusable && activatable) || !window);
 206
 207   // Activation change observers may change the focused window. If this happens
 208   // we must not adjust the focus below since this will clobber that change.
 209   aura::Window* last_focused_window = focused_window_;
 210   if (!updating_activation_)
 211     SetActiveWindow(reason, window, activatable);
 212
 213   // If the window's ActivationChangeObserver shifted focus to a valid window,
 214   // we don't want to focus the window we thought would be focused by default.
 215   bool activation_changed_focus = last_focused_window != focused_window_;
 216   if (!updating_focus_ && (!activation_changed_focus || !focused_window_)) {
 217     if (active_window_ && focusable)
 218       DCHECK(active_window_->Contains(focusable));
 219     SetFocusedWindow(focusable);
 220   }
 221 }
 222
 223 void FocusController::SetFocusedWindow(aura::Window* window) {
 224   if (updating_focus_ || window == focused_window_)
 225     return;
 226   DCHECK(rules_->CanFocusWindow(window));
 227   if (window)
 228     DCHECK_EQ(window, rules_->GetFocusableWindow(window));
 229
 230   base::AutoReset<bool> updating_focus(&updating_focus_, true);
 231   aura::Window* lost_focus = focused_window_;
 232
 233   // Allow for the window losing focus to be deleted during dispatch. If it is
 234   // deleted pass NULL to observers instead of a deleted window.
 235   aura::WindowTracker window_tracker;
 236   if (lost_focus)
 237     window_tracker.Add(lost_focus);
 238   if (focused_window_ && observer_manager_.IsObserving(focused_window_) &&
 239       focused_window_ != active_window_) {
 240     observer_manager_.Remove(focused_window_);
 241   }
 242   focused_window_ = window;
 243   if (focused_window_ && !observer_manager_.IsObserving(focused_window_))
 244     observer_manager_.Add(focused_window_);
 245
 246   FOR_EACH_OBSERVER(aura::client::FocusChangeObserver,
 247                     focus_observers_,
 248                     OnWindowFocused(focused_window_,
 249                                     window_tracker.Contains(lost_focus) ?
 250                                     lost_focus : NULL));
 251   if (window_tracker.Contains(lost_focus)) {
 252     aura::client::FocusChangeObserver* observer =
 253         aura::client::GetFocusChangeObserver(lost_focus);
 254     if (observer)
 255       observer->OnWindowFocused(focused_window_, lost_focus);
 256   }
 257   aura::client::FocusChangeObserver* observer =
 258       aura::client::GetFocusChangeObserver(focused_window_);
 259   if (observer) {
 260     observer->OnWindowFocused(
 261         focused_window_,
 262         window_tracker.Contains(lost_focus) ? lost_focus : NULL);
 263   }
 264 }
 265
 266 void FocusController::SetActiveWindow(
 267     aura::client::ActivationChangeObserver::ActivationReason reason,
 268     aura::Window* requested_window,
 269     aura::Window* window) {
 270   if (updating_activation_)
 271     return;
 272
 273   if (window == active_window_) {
 274     if (requested_window) {
 275       FOR_EACH_OBSERVER(aura::client::ActivationChangeObserver,
 276                         activation_observers_,
 277                         OnAttemptToReactivateWindow(requested_window,
 278                                                     active_window_));
 279     }
 280     return;
 281   }
 282
 283   DCHECK(rules_->CanActivateWindow(window));
 284   if (window)
 285     DCHECK_EQ(window, rules_->GetActivatableWindow(window));
 286
 287   base::AutoReset<bool> updating_activation(&updating_activation_, true);
 288   aura::Window* lost_activation = active_window_;
 289   // Allow for the window losing activation to be deleted during dispatch. If
 290   // it is deleted pass NULL to observers instead of a deleted window.
 291   aura::WindowTracker window_tracker;
 292   if (lost_activation)
 293     window_tracker.Add(lost_activation);
 294   if (active_window_ && observer_manager_.IsObserving(active_window_) &&
 295       focused_window_ != active_window_) {
 296     observer_manager_.Remove(active_window_);
 297   }
 298   active_window_ = window;
 299   if (active_window_ && !observer_manager_.IsObserving(active_window_))
 300     observer_manager_.Add(active_window_);
 301   if (active_window_) {
 302     StackTransientParentsBelowModalWindow(active_window_);
 303     active_window_->parent()->StackChildAtTop(active_window_);
 304   }
 305
 306   aura::client::ActivationChangeObserver* observer = NULL;
 307   if (window_tracker.Contains(lost_activation)) {
 308     observer = aura::client::GetActivationChangeObserver(lost_activation);
 309     if (observer)
 310       observer->OnWindowActivated(reason, active_window_, lost_activation);
 311   }
 312   observer = aura::client::GetActivationChangeObserver(active_window_);
 313   if (observer) {
 314     observer->OnWindowActivated(
 315         reason, active_window_,
 316         window_tracker.Contains(lost_activation) ? lost_activation : NULL);
 317   }
 318   FOR_EACH_OBSERVER(
 319       aura::client::ActivationChangeObserver, activation_observers_,
 320       OnWindowActivated(
 321           reason, active_window_,
 322           window_tracker.Contains(lost_activation) ? lost_activation : NULL));
 323 }
 324
 325 void FocusController::WindowLostFocusFromDispositionChange(
 326     aura::Window* window,
 327     aura::Window* next) {
 328   // TODO(beng): See if this function can be replaced by a call to
 329   //             FocusWindow().
 330   // Activation adjustments are handled first in the event of a disposition
 331   // changed. If an activation change is necessary, focus is reset as part of
 332   // that process so there's no point in updating focus independently.
 333   if (window == active_window_) {
 334     aura::Window* next_activatable = rules_->GetNextActivatableWindow(window);
 335     SetActiveWindow(aura::client::ActivationChangeObserver::ActivationReason::
 336                         WINDOW_DISPOSITION_CHANGED,
 337                     NULL, next_activatable);
 338     if (!(active_window_ && active_window_->Contains(focused_window_)))
 339       SetFocusedWindow(next_activatable);
 340   } else if (window->Contains(focused_window_)) {
 341     // Active window isn't changing, but focused window might be.
 342     SetFocusedWindow(rules_->GetFocusableWindow(next));
 343   }
 344 }
 345
 346 void FocusController::WindowFocusedFromInputEvent(aura::Window* window) {
 347   // Only focus |window| if it or any of its parents can be focused. Otherwise
 348   // FocusWindow() will focus the topmost window, which may not be the
 349   // currently focused one.
 350   if (rules_->CanFocusWindow(GetToplevelWindow(window))) {
 351     FocusAndActivateWindow(
 352         aura::client::ActivationChangeObserver::ActivationReason::INPUT_EVENT,
 353         window);
 354   }
 355 }
 356
 357 }  // namespace wm