A new menu system.

views/controls/menu/native_menu_win.cc

+// Copyright (c) 2009 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/native_menu_win.h"
+
+#include "app/l10n_util.h"
+#include "app/l10n_util_win.h"
+#include "base/logging.h"
+#include "base/stl_util-inl.h"
+#include "views/accelerator.h"
+#include "views/controls/menu/menu_2.h"
+
+namespace views {
+
+struct NativeMenuWin::ItemData {
+  // The Windows API requires that whoever creates the menus must own the
+  // strings used for labels, and keep them around for the lifetime of the
+  // created menu. So be it.
+  std::wstring label;
+
+  // Someone needs to own submenus, it may as well be us.
+  scoped_ptr<Menu2> submenu;
+};
+
+// TODO(beng): bring over owner draw from old menu system.
+class NativeMenuWin::MenuHostWindow {
+ public:
+  MenuHostWindow() {
+    RegisterClass();
+    hwnd_ = CreateWindowEx(l10n_util::GetExtendedStyles(), kWindowClassName,
+                           L"", 0, 0, 0, 0, 0, HWND_MESSAGE, NULL, NULL, NULL);
+    SetProp(hwnd_, kMenuHostWindowKey, this);
+  }
+
+  ~MenuHostWindow() {
+    DestroyWindow(hwnd_);
+  }
+
+  HWND hwnd() const { return hwnd_; }
+
+ private:
+  static const wchar_t* kMenuHostWindowKey;
+  static const wchar_t* kWindowClassName;
+
+  void RegisterClass() {
+    static bool registered = false;
+    if (registered)
+      return;
+
+    WNDCLASSEX wcex = {0};
+    wcex.cbSize = sizeof(WNDCLASSEX);
+    wcex.style = CS_DBLCLKS;
+    wcex.lpfnWndProc = &MenuHostWindowProc;
+    wcex.hbrBackground = reinterpret_cast<HBRUSH>(COLOR_WINDOW+1);
+    wcex.lpszClassName = kWindowClassName;
+    ATOM clazz = RegisterClassEx(&wcex);
+    DCHECK(clazz);
+    registered = true;
+  }
+
+  bool ProcessWindowMessage(HWND window,
+                            UINT message,
+                            WPARAM w_param,
+                            LPARAM l_param,
+                            LRESULT* l_result) {
+    return false;
+  }
+
+  static LRESULT CALLBACK MenuHostWindowProc(HWND window,
+                                             UINT message,
+                                             WPARAM w_param,
+                                             LPARAM l_param) {
+    MenuHostWindow* host =
+        reinterpret_cast<MenuHostWindow*>(GetProp(window, kMenuHostWindowKey));
+    LRESULT l_result = 0;
+    if (!host || !host->ProcessWindowMessage(window, message, w_param, l_param,
+                                             &l_result)) {
+      return DefWindowProc(window, message, w_param, l_param);
+    }
+    return l_result;
+  }
+
+  HWND hwnd_;
+
+  DISALLOW_COPY_AND_ASSIGN(MenuHostWindow);
+};
+
+// static
+const wchar_t* NativeMenuWin::MenuHostWindow::kWindowClassName =
+    L"ViewsMenuHostWindow";
+
+const wchar_t* NativeMenuWin::MenuHostWindow::kMenuHostWindowKey =
+    L"__MENU_HOST_WINDOW__";
+
+
+////////////////////////////////////////////////////////////////////////////////
+// NativeMenuWin, public:
+
+NativeMenuWin::NativeMenuWin(Menu2Model* model,
+                             Menu2Delegate* delegate,
+                             HWND system_menu_for)
+    : model_(model),
+      delegate_(delegate),
+      menu_(NULL),
+      owner_draw_(false),
+      system_menu_for_(system_menu_for),
+      first_item_index_(0) {
+}
+
+NativeMenuWin::~NativeMenuWin() {
+  STLDeleteContainerPointers(items_.begin(), items_.end());
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// NativeMenuWin, MenuWrapper implementation:
+
+void NativeMenuWin::RunMenuAt(const gfx::Point& point, int alignment) {
+  CreateHostWindow();
+  UpdateStates();
+  UINT flags = TPM_LEFTBUTTON | TPM_RETURNCMD | TPM_RECURSE;
+  flags |= GetAlignmentFlags(alignment);
+  UINT selected_command_id = TrackPopupMenuEx(menu_, flags, point.x(),
+                                              point.y(), host_window_->hwnd(),
+                                              NULL);
+  if (selected_command_id > 0) {
+    // Locate the correct delegate and model to notify about the selection.
+    // See comment in GetMenuForCommandId for details.
+    NativeMenuWin* menu = GetMenuForCommandId(selected_command_id);
+    menu->delegate_->ExecuteCommand(menu->model_, selected_command_id);
+  }
+}
+
+void NativeMenuWin::Rebuild() {
+  ResetNativeMenu();
+  owner_draw_ = model_->HasIcons();
+  first_item_index_ = model_->GetFirstItemIndex(GetNativeMenu());
+  for (int menu_index = first_item_index_;
+        menu_index < first_item_index_ + model_->GetItemCount(); ++menu_index) {
+    int model_index = menu_index - first_item_index_;
+    if (model_->GetTypeAt(model_index) == Menu2Model::TYPE_SEPARATOR)
+      AddSeparatorItemAt(menu_index, model_index);
+    else
+      AddMenuItemAt(menu_index, model_index);
+  }
+}
+
+void NativeMenuWin::UpdateStates() {
+  // A depth-first walk of the menu items, updating states.
+  for (int menu_index = first_item_index_;
+       menu_index < first_item_index_ + model_->GetItemCount(); ++menu_index) {
+    int model_index = menu_index - first_item_index_;
+    SetMenuItemState(menu_index, model_->IsEnabledAt(model_index),
+                     model_->IsItemCheckedAt(model_index), false);
+    if (model_->IsLabelDynamicAt(model_index)) {
+      SetMenuItemLabel(menu_index, model_index,
+                       model_->GetLabelAt(model_index));
+    }
+    Menu2* submenu = items_.at(model_index)->submenu.get();
+    if (submenu)
+      submenu->UpdateStates();
+  }
+}
+
+gfx::NativeMenu NativeMenuWin::GetNativeMenu() const {
+  return menu_;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// NativeMenuWin, private:
+
+bool NativeMenuWin::IsSeparatorItemAt(int menu_index) const {
+  MENUITEMINFO mii = {0};
+  mii.cbSize = sizeof(mii);
+  mii.fMask = MIIM_FTYPE;
+  GetMenuItemInfo(menu_, menu_index, MF_BYPOSITION, &mii);
+  return !!(mii.fType & MF_SEPARATOR);
+}
+
+void NativeMenuWin::AddMenuItemAt(int menu_index, int model_index) {
+  MENUITEMINFO mii = {0};
+  mii.cbSize = sizeof(mii);
+  mii.fMask = MIIM_FTYPE | MIIM_ID | MIIM_DATA;
+  if (!owner_draw_)
+    mii.fType = MFT_STRING;
+  else
+    mii.fType = MFT_OWNERDRAW;
+  mii.dwItemData = reinterpret_cast<ULONG_PTR>(this);
+
+  ItemData* item_data = new ItemData;
+  Menu2Model::ItemType type = model_->GetTypeAt(model_index);
+  if (type == Menu2Model::TYPE_SUBMENU) {
+    item_data->submenu.reset(new Menu2(model_->GetSubmenuModelAt(model_index),
+                                       delegate_));
+    mii.fMask |= MIIM_SUBMENU;
+    mii.hSubMenu = item_data->submenu->GetNativeMenu();
+  } else {
+    if (type == Menu2Model::TYPE_RADIO)
+      mii.fType |= MFT_RADIOCHECK;
+    mii.wID = model_->GetCommandIdAt(model_index);
+  }
+  items_.insert(items_.begin() + model_index, item_data);
+  UpdateMenuItemInfoForString(&mii, model_index,
+                              model_->GetLabelAt(model_index));
+  InsertMenuItem(menu_, menu_index, TRUE, &mii);
+}
+
+void NativeMenuWin::AddSeparatorItemAt(int menu_index, int model_index) {
+  MENUITEMINFO mii = {0};
+  mii.cbSize = sizeof(mii);
+  mii.fMask = MIIM_FTYPE;
+  mii.fType = MFT_SEPARATOR;
+  // Insert a dummy entry into our label list so we can index directly into it
+  // using item indices if need be.
+  items_.insert(items_.begin() + model_index, new ItemData);
+  InsertMenuItem(menu_, menu_index, TRUE, &mii);
+}
+
+void NativeMenuWin::SetMenuItemState(int menu_index, bool enabled, bool checked,
+                                     bool is_default) {
+  if (IsSeparatorItemAt(menu_index))
+    return;
+
+  UINT state = enabled ? MFS_ENABLED : MFS_DISABLED;
+  if (checked)
+    state |= MFS_CHECKED;
+  if (is_default)
+    state |= MFS_DEFAULT;
+
+  MENUITEMINFO mii = {0};
+  mii.cbSize = sizeof(mii);
+  mii.fMask = MIIM_STATE;
+  mii.fState = state;
+  SetMenuItemInfo(menu_, menu_index, MF_BYPOSITION, &mii);
+}
+
+void NativeMenuWin::SetMenuItemLabel(int menu_index,
+                                     int model_index,
+                                     const std::wstring& label) {
+  if (IsSeparatorItemAt(menu_index))
+    return;
+
+  MENUITEMINFO mii = {0};
+  mii.cbSize = sizeof(mii);
+  UpdateMenuItemInfoForString(&mii, model_index, label);
+  if (!owner_draw_)
+    SetMenuItemInfo(menu_, menu_index, MF_BYPOSITION, &mii);
+}
+
+void NativeMenuWin::UpdateMenuItemInfoForString(
+    MENUITEMINFO* mii,
+    int model_index,
+    const std::wstring& label) {
+  std::wstring formatted = label;
+  Menu2Model::ItemType type = model_->GetTypeAt(model_index);
+  if (type != Menu2Model::TYPE_SUBMENU) {
+    // Add accelerator details to the label if provided.
+    views::Accelerator accelerator(0, false, false, false);
+    if (model_->GetAcceleratorAt(model_index, &accelerator)) {
+      formatted += L"\t";
+      formatted += accelerator.GetShortcutText();
+    }
+  }
+
+  // Update the owned string, since Windows will want us to keep this new
+  // version around.
+  items_[model_index]->label = formatted;
+
+  // Windows only requires a pointer to the label string if it's going to be
+  // doing the drawing.
+  if (!owner_draw_) {
+    mii->fMask |= MIIM_STRING;
+    mii->dwTypeData =
+        const_cast<wchar_t*>(items_.at(model_index)->label.c_str());
+  }
+}
+
+NativeMenuWin* NativeMenuWin::GetMenuForCommandId(UINT command_id) const {
+  // Menus can have nested submenus. In the views Menu system, each submenu is
+  // wrapped in a NativeMenu instance, which may have a different model and
+  // delegate from the parent menu. The trouble is, RunMenuAt is called on the
+  // parent NativeMenuWin, and so it's not possible to assume that we can just
+  // dispatch the command id returned by TrackPopupMenuEx to the parent's
+  // delegate. For this reason, we stow a pointer on every menu item we create
+  // to the NativeMenuWin that most closely contains it. Fortunately, Windows
+  // provides GetMenuItemInfo, which can walk down the menu item tree from
+  // the root |menu_| to find the data for a given item even if it's in a
+  // submenu.
+  MENUITEMINFO mii = {0};
+  mii.cbSize = sizeof(mii);
+  mii.fMask = MIIM_DATA;
+  GetMenuItemInfo(menu_, command_id, FALSE, &mii);
+  return reinterpret_cast<NativeMenuWin*>(mii.dwItemData);
+}
+
+UINT NativeMenuWin::GetAlignmentFlags(int alignment) const {
+  bool rtl = l10n_util::GetTextDirection() == l10n_util::RIGHT_TO_LEFT;
+  UINT alignment_flags = TPM_TOPALIGN;
+  if (alignment == Menu2::ALIGN_TOPLEFT)
+    alignment_flags |= TPM_LEFTALIGN;
+  else if (alignment == Menu2::ALIGN_TOPRIGHT)
+    alignment_flags |= TPM_RIGHTALIGN;
+  return alignment_flags;
+}
+
+void NativeMenuWin::ResetNativeMenu() {
+  if (IsWindow(system_menu_for_)) {
+    if (menu_)
+      GetSystemMenu(system_menu_for_, TRUE);
+    menu_ = GetSystemMenu(system_menu_for_, FALSE);
+  } else {
+    if (menu_)
+      DestroyMenu(menu_);
+    menu_ = CreatePopupMenu();
+  }
+}
+
+void NativeMenuWin::CreateHostWindow() {
+  if (!host_window_.get())
+    host_window_.reset(new MenuHostWindow());
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// SystemMenuModel:
+
+SystemMenuModel::SystemMenuModel(SimpleMenuModel::Delegate* delegate)
+    : SimpleMenuModel(delegate) {
+}
+
+SystemMenuModel::~SystemMenuModel() {
+}
+
+int SystemMenuModel::GetFirstItemIndex(gfx::NativeMenu native_menu) const {
+  // We allow insertions before last item (Close).
+  return std::max(0, GetMenuItemCount(native_menu) - 1);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// MenuWrapper, public:
+
+// static
+MenuWrapper* MenuWrapper::CreateWrapper(Menu2* menu) {
+  return new NativeMenuWin(menu->model(), menu->delegate(), NULL);
+}
+
+}  // namespace views