Moves management of transients out of Window

ui/views/corewm/transient_window_manager.cc

+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/views/corewm/transient_window_manager.h"
+
+#include <algorithm>
+#include <functional>
+
+#include "base/auto_reset.h"
+#include "base/stl_util.h"
+#include "ui/aura/window.h"
+#include "ui/aura/window_property.h"
+#include "ui/views/corewm/transient_window_stacking_client.h"
+#include "ui/views/corewm/window_util.h"
+
+using aura::Window;
+
+namespace views {
+namespace corewm {
+
+DEFINE_OWNED_WINDOW_PROPERTY_KEY(TransientWindowManager, kPropertyKey, NULL);
+
+TransientWindowManager::~TransientWindowManager() {
+}
+
+// static
+TransientWindowManager* TransientWindowManager::Get(Window* window) {
+  TransientWindowManager* manager = window->GetProperty(kPropertyKey);
+  if (!manager) {
+    manager = new TransientWindowManager(window);
+    window->SetProperty(kPropertyKey, manager);
+  }
+  return manager;
+}
+
+// static
+const TransientWindowManager* TransientWindowManager::Get(
+    const Window* window) {
+  return window->GetProperty(kPropertyKey);
+}
+
+void TransientWindowManager::AddTransientChild(Window* child) {
+  // TransientWindowStackingClient does the stacking of transient windows. If it
+  // isn't installed stacking is going to be wrong.
+  DCHECK(TransientWindowStackingClient::instance_);
+
+  TransientWindowManager* child_manager = Get(child);
+  if (child_manager->transient_parent_)
+    Get(child_manager->transient_parent_)->RemoveTransientChild(child);
+  DCHECK(std::find(transient_children_.begin(), transient_children_.end(),
+                   child) == transient_children_.end());
+  transient_children_.push_back(child);
+  child_manager->transient_parent_ = window_;
+  FOR_EACH_OBSERVER(WindowObserver, window_->observers_,
+                    OnAddTransientChild(window_, child));
+}
+
+void TransientWindowManager::RemoveTransientChild(Window* child) {
+  Windows::iterator i =
+      std::find(transient_children_.begin(), transient_children_.end(), child);
+  DCHECK(i != transient_children_.end());
+  transient_children_.erase(i);
+  TransientWindowManager* child_manager = Get(child);
+  DCHECK_EQ(window_, child_manager->transient_parent_);
+  child_manager->transient_parent_ = NULL;
+  FOR_EACH_OBSERVER(WindowObserver, window_->observers_,
+                    OnRemoveTransientChild(window_, child));
+}
+
+bool TransientWindowManager::IsStackingTransient(
+    const aura::Window* child,
+    const aura::Window* target) const {
+  return stacking_pair_ && stacking_pair_->child == child &&
+      stacking_pair_->target == target;
+}
+
+TransientWindowManager::TransientWindowManager(Window* window)
+    : window_(window),
+      transient_parent_(NULL),
+      stacking_pair_(NULL) {
+  window_->AddObserver(this);
+}
+
+void TransientWindowManager::OnChildStackingChanged(aura::Window* child) {
+  // Do nothing if we initiated the stacking change.
+  // TODO(sky): change args to OnWindowStackingChanged() so that this lookup
+  // can be simpler.
+  if (stacking_pair_ && stacking_pair_->child == child) {
+    Windows::const_iterator child_i = std::find(
+        window_->children().begin(), window_->children().end(), child);
+    DCHECK(child_i != window_->children().end());
+    if (child_i != window_->children().begin() &&
+        (*(child_i - 1) == stacking_pair_->target))
+      return;
+  }
+
+  // Stack any transient children that share the same parent to be in front of
+  // |child|. The existing stacking order is preserved by iterating backwards
+  // and always stacking on top.
+  Window::Windows children(window_->children());
+  for (Window::Windows::reverse_iterator it = children.rbegin();
+       it != children.rend(); ++it) {
+    if ((*it) != child && HasTransientAncestor(*it, child)) {
+      StackingPair pair(*it, child);
+      base::AutoReset<StackingPair*> resetter(&stacking_pair_, &pair);
+      window_->StackChildAbove((*it), child);
+    }
+  }
+}
+
+void TransientWindowManager::OnWindowVisibilityChanging(Window* window,
+                                                        bool visible) {
+  // TODO(sky): move handling of becoming visible here.
+  if (!visible) {
+    std::for_each(transient_children_.begin(), transient_children_.end(),
+                  std::mem_fun(&Window::Hide));
+  }
+}
+
+void TransientWindowManager::OnWindowStackingChanged(Window* window) {
+  TransientWindowManager* parent_manager = Get(window->parent());
+  parent_manager->OnChildStackingChanged(window);
+}
+
+void TransientWindowManager::OnWindowDestroying(Window* window) {
+  // TODO(sky): remove notes after safely landing and baking.
+
+  // Removes ourselves from our transient parent (if it hasn't been done by the
+  // RootWindow).
+  // NOTE: This use to be done after children where removed, now it is before.
+  if (transient_parent_) {
+    TransientWindowManager::Get(transient_parent_)->RemoveTransientChild(
+        window_);
+  }
+
+  // Destroy transient children, only after we've removed ourselves from our
+  // parent, as destroying an active transient child may otherwise attempt to
+  // refocus us.
+  // NOTE: this use to be after removed from parent, now its before.
+  Windows transient_children(transient_children_);
+  STLDeleteElements(&transient_children);
+  DCHECK(transient_children_.empty());
+}
+
+}  // namespace corewm
+}  // namespace views