ui/wm/core/transient_window_manager.cc

   1 // Copyright 2014 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/transient_window_manager.h"
   6
   7 #include <algorithm>
   8 #include <functional>
   9
  10 #include "base/auto_reset.h"
  11 #include "base/stl_util.h"
  12 #include "ui/aura/window.h"
  13 #include "ui/aura/window_property.h"
  14 #include "ui/wm/core/transient_window_observer.h"
  15 #include "ui/wm/core/transient_window_stacking_client.h"
  16 #include "ui/wm/core/window_util.h"
  17
  18 using aura::Window;
  19
  20 namespace wm {
  21
  22 DEFINE_OWNED_WINDOW_PROPERTY_KEY(TransientWindowManager, kPropertyKey, NULL);
  23
  24 TransientWindowManager::~TransientWindowManager() {
  25 }
  26
  27 // static
  28 TransientWindowManager* TransientWindowManager::Get(Window* window) {
  29   TransientWindowManager* manager = window->GetProperty(kPropertyKey);
  30   if (!manager) {
  31     manager = new TransientWindowManager(window);
  32     window->SetProperty(kPropertyKey, manager);
  33   }
  34   return manager;
  35 }
  36
  37 // static
  38 const TransientWindowManager* TransientWindowManager::Get(
  39     const Window* window) {
  40   return window->GetProperty(kPropertyKey);
  41 }
  42
  43 void TransientWindowManager::AddObserver(TransientWindowObserver* observer) {
  44   observers_.AddObserver(observer);
  45 }
  46
  47 void TransientWindowManager::RemoveObserver(TransientWindowObserver* observer) {
  48   observers_.RemoveObserver(observer);
  49 }
  50
  51 void TransientWindowManager::AddTransientChild(Window* child) {
  52   // TransientWindowStackingClient does the stacking of transient windows. If it
  53   // isn't installed stacking is going to be wrong.
  54   DCHECK(TransientWindowStackingClient::instance_);
  55
  56   TransientWindowManager* child_manager = Get(child);
  57   if (child_manager->transient_parent_)
  58     Get(child_manager->transient_parent_)->RemoveTransientChild(child);
  59   DCHECK(std::find(transient_children_.begin(), transient_children_.end(),
  60                    child) == transient_children_.end());
  61   transient_children_.push_back(child);
  62   child_manager->transient_parent_ = window_;
  63
  64   // Restack |child| properly above its transient parent, if they share the same
  65   // parent.
  66   if (child->parent() == window_->parent())
  67     RestackTransientDescendants();
  68
  69   FOR_EACH_OBSERVER(TransientWindowObserver, observers_,
  70                     OnTransientChildAdded(window_, child));
  71 }
  72
  73 void TransientWindowManager::RemoveTransientChild(Window* child) {
  74   Windows::iterator i =
  75       std::find(transient_children_.begin(), transient_children_.end(), child);
  76   DCHECK(i != transient_children_.end());
  77   transient_children_.erase(i);
  78   TransientWindowManager* child_manager = Get(child);
  79   DCHECK_EQ(window_, child_manager->transient_parent_);
  80   child_manager->transient_parent_ = NULL;
  81
  82   // If |child| and its former transient parent share the same parent, |child|
  83   // should be restacked properly so it is not among transient children of its
  84   // former parent, anymore.
  85   if (window_->parent() == child->parent())
  86     RestackTransientDescendants();
  87
  88   FOR_EACH_OBSERVER(TransientWindowObserver, observers_,
  89                     OnTransientChildRemoved(window_, child));
  90 }
  91
  92 bool TransientWindowManager::IsStackingTransient(
  93     const aura::Window* target) const {
  94   return stacking_target_ == target;
  95 }
  96
  97 TransientWindowManager::TransientWindowManager(Window* window)
  98     : window_(window),
  99       transient_parent_(NULL),
 100       stacking_target_(NULL) {
 101   window_->AddObserver(this);
 102 }
 103
 104 void TransientWindowManager::RestackTransientDescendants() {
 105   Window* parent = window_->parent();
 106   if (!parent)
 107     return;
 108
 109   // Stack any transient children that share the same parent to be in front of
 110   // |window_|. The existing stacking order is preserved by iterating backwards
 111   // and always stacking on top.
 112   Window::Windows children(parent->children());
 113   for (Window::Windows::reverse_iterator it = children.rbegin();
 114        it != children.rend(); ++it) {
 115     if ((*it) != window_ && HasTransientAncestor(*it, window_)) {
 116       TransientWindowManager* descendant_manager = Get(*it);
 117       base::AutoReset<Window*> resetter(
 118           &descendant_manager->stacking_target_,
 119           window_);
 120       parent->StackChildAbove((*it), window_);
 121     }
 122   }
 123 }
 124
 125 void TransientWindowManager::OnWindowParentChanged(aura::Window* window,
 126                                                    aura::Window* parent) {
 127   DCHECK_EQ(window_, window);
 128   // Stack |window| properly if it is transient child of a sibling.
 129   Window* transient_parent = wm::GetTransientParent(window);
 130   if (transient_parent && transient_parent->parent() == parent) {
 131     TransientWindowManager* transient_parent_manager =
 132         Get(transient_parent);
 133     transient_parent_manager->RestackTransientDescendants();
 134   }
 135 }
 136
 137 void TransientWindowManager::OnWindowVisibilityChanging(Window* window,
 138                                                         bool visible) {
 139   // TODO(sky): move handling of becoming visible here.
 140   if (!visible) {
 141     std::for_each(transient_children_.begin(), transient_children_.end(),
 142                   std::mem_fun(&Window::Hide));
 143   }
 144 }
 145
 146 void TransientWindowManager::OnWindowStackingChanged(Window* window) {
 147   DCHECK_EQ(window_, window);
 148
 149   // Do nothing if we initiated the stacking change.
 150   const TransientWindowManager* transient_manager =
 151       Get(static_cast<const Window*>(window));
 152   if (transient_manager && transient_manager->stacking_target_) {
 153     Windows::const_iterator window_i = std::find(
 154         window->parent()->children().begin(),
 155         window->parent()->children().end(),
 156         window);
 157     DCHECK(window_i != window->parent()->children().end());
 158     if (window_i != window->parent()->children().begin() &&
 159         (*(window_i - 1) == transient_manager->stacking_target_))
 160       return;
 161   }
 162
 163   RestackTransientDescendants();
 164 }
 165
 166 void TransientWindowManager::OnWindowDestroying(Window* window) {
 167   // Removes ourselves from our transient parent (if it hasn't been done by the
 168   // RootWindow).
 169   if (transient_parent_) {
 170     TransientWindowManager::Get(transient_parent_)->RemoveTransientChild(
 171         window_);
 172   }
 173
 174   // Destroy transient children, only after we've removed ourselves from our
 175   // parent, as destroying an active transient child may otherwise attempt to
 176   // refocus us.
 177   Windows transient_children(transient_children_);
 178   STLDeleteElements(&transient_children);
 179   DCHECK(transient_children_.empty());
 180 }
 181
 182 }  // namespace wm