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