Moves ownership of MenuItemView to MenuRunner as well as responbility

views/controls/menu/menu_runner.cc

 // Copyright (c) 2011 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 "views/controls/menu/menu_runner.h"
 
+#include <set>
+
+#include "views/controls/button/menu_button.h"
+#include "views/controls/menu/menu_controller.h"
+#include "views/controls/menu/menu_controller_delegate.h"
+#include "views/controls/menu/menu_delegate.h"
+
+#if defined(OS_WIN)
+#include "base/win/win_util.h"
+#endif
+
 namespace views {
 
-// Manages the menu. To destroy a Holder invoke Release(). Release() deletes
-// immediately if the menu isn't showing. If the menu is showing Release()
-// cancels the menu and when the nested RunMenuAt() call returns, deletes itself
-// and the menu.
-class MenuRunner::Holder {
+namespace internal {
+
+// Manages the menu. To destroy a MenuRunnerImpl invoke Release(). Release()
+// deletes immediately if the menu isn't showing. If the menu is showing
+// Release() cancels the menu and when the nested RunMenuAt() call returns
+// deletes itself and the menu.
+class MenuRunnerImpl : public internal::MenuControllerDelegate {
  public:
-  explicit Holder(MenuItemView* menu);
+  explicit MenuRunnerImpl(MenuItemView* menu);
+
+  MenuItemView* menu() { return menu_; }
 
   // See description above class for details.
   void Release();
 
   // Runs the menu.
-  void RunMenuAt(Widget* parent,
-                 MenuButton* button,
-                 const gfx::Rect& bounds,
-                 MenuItemView::AnchorPosition anchor,
-                 bool has_mnemonics);
+  MenuRunner::RunResult RunMenuAt(Widget* parent,
+                                  MenuButton* button,
+                                  const gfx::Rect& bounds,
+                                  MenuItemView::AnchorPosition anchor,
+                                  int32 types) WARN_UNUSED_RESULT;
+
+  void Cancel();
+
+  // MenuControllerDelegate:
+  virtual void DropMenuClosed(NotifyType type, MenuItemView* menu) OVERRIDE;
+  virtual void SiblingMenuCreated(MenuItemView* menu) OVERRIDE;
 
  private:
-  ~Holder();
+  ~MenuRunnerImpl();
 
-  scoped_ptr<MenuItemView> menu_;
+  // Cleans up after the menu is no longer showing. |result| is the menu that
+  // the user selected, or NULL if nothing was selected.
+  MenuRunner::RunResult MenuDone(MenuItemView* result, int mouse_event_flags);
+
+  // Returns true if mnemonics should be shown in the menu.
+  bool ShouldShowMnemonics(MenuButton* button);
+
+  // The menu. We own this. We don't use scoped_ptr as the destructor is
+  // protected and we're a friend.
+  MenuItemView* menu_;
+
+  // Any sibling menus. Does not include |menu_|. We own these too.
+  std::set<MenuItemView*> sibling_menus_;
+
+  // Created and set as the delegate of the MenuItemView if Release() is
+  // invoked.  This is done to make sure the delegate isn't notified after
+  // Release() is invoked. We do this as we assume the delegate is no longer
+  // valid if MenuRunner has been deleted.
+  scoped_ptr<MenuDelegate> empty_delegate_;
 
   // Are we in run waiting for it to return?
   bool running_;
 
   // Set if |running_| and Release() has been invoked.
   bool delete_after_run_;
 
-  DISALLOW_COPY_AND_ASSIGN(Holder);
+  // Are we running for a drop?
+  bool for_drop_;
+
+  // The controller.
+  MenuController* controller_;
+
+  // Do we own the controller?
+  bool owns_controller_;
+
+  DISALLOW_COPY_AND_ASSIGN(MenuRunnerImpl);
 };
 
-MenuRunner::Holder::Holder(MenuItemView* menu)
+MenuRunnerImpl::MenuRunnerImpl(MenuItemView* menu)
     : menu_(menu),
       running_(false),
-      delete_after_run_(false) {
+      delete_after_run_(false),
+      for_drop_(false),
+      controller_(NULL),
+      owns_controller_(false) {
 }
 
-void MenuRunner::Holder::Release() {
+void MenuRunnerImpl::Release() {
   if (running_) {
+    if (delete_after_run_)
+      return;  // We already canceled.
+
     // The menu is running a nested message loop, we can't delete it now
     // otherwise the stack would be in a really bad state (many frames would
     // have deleted objects on them). Instead cancel the menu, when it returns
     // Holder will delete itself.
     delete_after_run_ = true;
+
+    // Swap in a different delegate. That way we know the original MenuDelegate
+    // won't be notified later on (when it's likely already been deleted).
+    if (!empty_delegate_.get())
+      empty_delegate_.reset(new MenuDelegate());
+    menu_->set_delegate(empty_delegate_.get());
+
     menu_->Cancel();
   } else {
     delete this;
   }
 }
 
-void MenuRunner::Holder::RunMenuAt(Widget* parent,
-                                   MenuButton* button,
-                                   const gfx::Rect& bounds,
-                                   MenuItemView::AnchorPosition anchor,
-                                   bool has_mnemonics) {
+MenuRunner::RunResult MenuRunnerImpl::RunMenuAt(
+    Widget* parent,
+    MenuButton* button,
+    const gfx::Rect& bounds,
+    MenuItemView::AnchorPosition anchor,
+    int32 types) {
   if (running_) {
     // Ignore requests to show the menu while it's already showing. MenuItemView
     // doesn't handle this very well (meaning it crashes).
-    return;
+    return MenuRunner::NORMAL_EXIT;
+  }
+
+  MenuController* controller = MenuController::GetActiveInstance();
+  if (controller) {
+    if ((types & MenuRunner::IS_NESTED) != 0) {
+      if (!controller->IsBlockingRun()) {
+        controller->CancelAll();
+        controller = NULL;
+      }
+    } else {
+      // There's some other menu open and we're not nested. Cancel the menu.
+      controller->CancelAll();
+      if ((types & MenuRunner::FOR_DROP) == 0) {
+        // We can't open another menu, otherwise the message loop would become
+        // twice nested. This isn't necessarily a problem, but generally isn't
+        // expected.
+        return MenuRunner::NORMAL_EXIT;
+      }
+      // Drop menus don't block the message loop, so it's ok to create a new
+      // MenuController.
+      controller = NULL;
+    }
   }
   running_ = true;
-  menu_->RunMenuAt(parent, button, bounds, anchor, has_mnemonics);
+  for_drop_ = (types & MenuRunner::FOR_DROP) != 0;
+  bool has_mnemonics = (types & MenuRunner::HAS_MNEMONICS) != 0 && !for_drop_;
+  menu_->PrepareForRun(has_mnemonics,
+                       !for_drop_ && ShouldShowMnemonics(button));
+  int mouse_event_flags = 0;
+  owns_controller_ = false;
+  if (!controller) {
+    // No menus are showing, show one.
+    controller = new MenuController(!for_drop_, this);
+    owns_controller_ = true;
+  }
+  controller_ = controller;
+  menu_->set_controller(controller_);
+
+  // Run the loop.
+  MenuItemView* result = controller->Run(parent, button, menu_, bounds, anchor,
+                                         &mouse_event_flags);
+
+  if (for_drop_) {
+    // Drop menus return immediately. We finish processing in DropMenuClosed.
+    return MenuRunner::NORMAL_EXIT;
+  }
+
+  return MenuDone(result, mouse_event_flags);
+}
+
+void MenuRunnerImpl::Cancel() {
+  if (running_)
+    controller_->Cancel(MenuController::EXIT_ALL);
+}
+
+void MenuRunnerImpl::DropMenuClosed(NotifyType type, MenuItemView* menu) {
+  MenuDone(NULL, 0);
+
+  if (type == NOTIFY_DELEGATE && menu->GetDelegate()) {
+    // Delegate is null when invoked from the destructor.
+    menu->GetDelegate()->DropMenuClosed(menu);
+  }
+}
+
+void MenuRunnerImpl::SiblingMenuCreated(MenuItemView* menu) {
+  if (menu != menu_ && sibling_menus_.count(menu) == 0)
+    sibling_menus_.insert(menu);
+}
+
+MenuRunnerImpl::~MenuRunnerImpl() {
+  delete menu_;
+  for (std::set<MenuItemView*>::iterator i = sibling_menus_.begin();
+       i != sibling_menus_.end(); ++i)
+    delete *i;
+}
+
+MenuRunner::RunResult MenuRunnerImpl::MenuDone(MenuItemView* result,
+                                               int mouse_event_flags) {
+  menu_->RemoveEmptyMenus();
+  menu_->set_controller(NULL);
+
+  if (owns_controller_) {
+    // We created the controller and need to delete it.
+    delete controller_;
+    owns_controller_ = false;
+  }
+  controller_ = NULL;
+  // Make sure all the windows we created to show the menus have been
+  // destroyed.
+  menu_->DestroyAllMenuHosts();
   if (delete_after_run_) {
     delete this;
-    return;
+    return MenuRunner::MENU_DELETED;
   }
   running_ = false;
+  if (result && menu_->GetDelegate()) {
+    menu_->GetDelegate()->ExecuteCommand(result->GetCommand(),
+                                         mouse_event_flags);
+  }
+  return MenuRunner::NORMAL_EXIT;
 }
 
-MenuRunner::Holder::~Holder() {
+bool MenuRunnerImpl::ShouldShowMnemonics(MenuButton* button) {
+  // Show mnemonics if the button has focus or alt is pressed.
+  bool show_mnemonics = button ? button->HasFocus() : false;
+#if defined(OS_WIN)
+  // We don't currently need this on gtk as showing the menu gives focus to the
+  // button first.
+  if (!show_mnemonics)
+    show_mnemonics = base::win::IsAltPressed();
+#endif
+  return show_mnemonics;
 }
 
-MenuRunner::MenuRunner(MenuItemView* menu) : holder_(new Holder(menu)) {
+}  // namespace internal
+
+MenuRunner::MenuRunner(MenuItemView* menu)
+    : holder_(new internal::MenuRunnerImpl(menu)) {
 }
 
 MenuRunner::~MenuRunner() {
   holder_->Release();
 }
 
-void MenuRunner::RunMenuAt(Widget* parent,
-                           MenuButton* button,
-                           const gfx::Rect& bounds,
-                           MenuItemView::AnchorPosition anchor,
-                           bool has_mnemonics) {
-  holder_->RunMenuAt(parent, button, bounds, anchor, has_mnemonics);
+MenuItemView* MenuRunner::GetMenu() {
+  return holder_->menu();
+}
+
+MenuRunner::RunResult MenuRunner::RunMenuAt(Widget* parent,
+                                            MenuButton* button,
+                                            const gfx::Rect& bounds,
+                                            MenuItemView::AnchorPosition anchor,
+                                            int32 types) {
+  return holder_->RunMenuAt(parent, button, bounds, anchor, types);
+}
+
+void MenuRunner::Cancel() {
+  holder_->Cancel();
 }
 
 }  // namespace views