ash/focus_cycler.cc

   1 // Copyright 2012 The Chromium Authors
   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/focus_cycler.h"
   6
   7 #include "ash/shell.h"
   8 #include "ash/wm/mru_window_tracker.h"
   9 #include "ash/wm/window_state.h"
  10 #include "ash/wm/window_util.h"
  11 #include "base/ranges/algorithm.h"
  12 #include "ui/views/accessible_pane_view.h"
  13 #include "ui/views/focus/focus_search.h"
  14 #include "ui/views/widget/widget.h"
  15 #include "ui/views/widget/widget_delegate.h"
  16 #include "ui/wm/public/activation_client.h"
  17
  18 namespace ash {
  19
  20 namespace {
  21
  22 bool HasFocusableWindow() {
  23   return !Shell::Get()
  24               ->mru_window_tracker()
  25               ->BuildMruWindowList(kActiveDesk)
  26               .empty();
  27 }
  28
  29 }  // namespace
  30
  31 FocusCycler::FocusCycler() : widget_activating_(nullptr) {}
  32
  33 FocusCycler::~FocusCycler() = default;
  34
  35 void FocusCycler::AddWidget(views::Widget* widget) {
  36   widgets_.push_back(widget);
  37 }
  38
  39 void FocusCycler::RemoveWidget(views::Widget* widget) {
  40   auto iter = base::ranges::find(widgets_, widget);
  41   if (iter != widgets_.end())
  42     widgets_.erase(iter);
  43 }
  44
  45 void FocusCycler::RotateFocus(Direction direction, bool move_onto_next_widget) {
  46   if (aura::Window* window = window_util::GetActiveWindow(); window) {
  47     views::Widget* widget = views::Widget::GetWidgetForNativeView(window);
  48     // First try to rotate focus within the active widget. If that succeeds,
  49     // we're done.
  50     if (widget && !move_onto_next_widget &&
  51         widget->GetFocusManager()->RotatePaneFocus(
  52             direction == BACKWARD ? views::FocusManager::Direction::kBackward
  53                                   : views::FocusManager::Direction::kForward,
  54             views::FocusManager::FocusCycleWrapping::kDisabled)) {
  55       return;
  56     }
  57   }
  58
  59   const bool has_window = HasFocusableWindow();
  60   int index = 0;
  61   int count = static_cast<int>(widgets_.size());
  62   int browser_index = has_window ? count : -1;
  63
  64   for (; index < count; ++index) {
  65     if (widgets_[index]->IsActive())
  66       break;
  67   }
  68
  69   int start_index = index;
  70
  71   if (has_window)
  72     ++count;
  73
  74   for (;;) {
  75     if (direction == FORWARD)
  76       index = (index + 1) % count;
  77     else
  78       index = ((index - 1) + count) % count;
  79
  80     // Ensure that we don't loop more than once.
  81     if (index == start_index)
  82       break;
  83
  84     if (index == browser_index) {
  85       // Activate the most recently active browser window.
  86       MruWindowTracker::WindowList mru_windows(
  87           Shell::Get()->mru_window_tracker()->BuildMruWindowList(kActiveDesk));
  88       if (mru_windows.empty())
  89         break;
  90       auto* window = mru_windows.front();
  91       WindowState::Get(window)->Activate();
  92       views::Widget* widget = views::Widget::GetWidgetForNativeView(window);
  93       if (!widget)
  94         break;
  95       views::FocusManager* focus_manager = widget->GetFocusManager();
  96       focus_manager->ClearFocus();
  97       focus_manager->RotatePaneFocus(
  98           direction == BACKWARD ? views::FocusManager::Direction::kBackward
  99                                 : views::FocusManager::Direction::kForward,
 100           views::FocusManager::FocusCycleWrapping::kEnabled);
 101       break;
 102     } else {
 103       if (FocusWidget(widgets_[index]))
 104         break;
 105     }
 106   }
 107 }
 108
 109 bool FocusCycler::FocusWidget(views::Widget* widget) {
 110   // If the target is PIP window, temporarily make it activatable.
 111   if (WindowState::Get(widget->GetNativeWindow())->IsPip())
 112     widget->widget_delegate()->SetCanActivate(true);
 113
 114   // Note: It is not necessary to set the focus directly to the pane since that
 115   // will be taken care of by the widget activation.
 116   widget_activating_ = widget;
 117   widget->Activate();
 118   widget_activating_ = nullptr;
 119   return widget->IsActive();
 120 }
 121
 122 views::Widget* FocusCycler::FindWidget(
 123     base::RepeatingCallback<bool(views::Widget*)> callback) {
 124   for (auto* widget : widgets_) {
 125     if (callback.Run(widget))
 126       return widget;
 127   }
 128   return nullptr;
 129 }
 130
 131 }  // namespace ash