ui/views/controls/menu/menu_key_event_handler.cc

   1 // Copyright 2015 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/views/controls/menu/menu_key_event_handler.h"
   6
   7 #include "ui/aura/env.h"
   8 #include "ui/events/keycodes/keyboard_code_conversion.h"
   9 #include "ui/views/controls/menu/menu_controller.h"
  10 #include "ui/views/views_delegate.h"
  11
  12 namespace views {
  13
  14 namespace {
  15
  16 const int kKeyFlagsMask = ui::EF_CONTROL_DOWN | ui::EF_ALT_DOWN;
  17
  18 }  // namespace
  19
  20 MenuKeyEventHandler::MenuKeyEventHandler() {
  21   aura::Env::GetInstanceDontCreate()->PrependPreTargetHandler(this);
  22 }
  23
  24 MenuKeyEventHandler::~MenuKeyEventHandler() {
  25   aura::Env::GetInstanceDontCreate()->RemovePreTargetHandler(this);
  26 }
  27
  28 void MenuKeyEventHandler::OnKeyEvent(ui::KeyEvent* event) {
  29   MenuController* menu_controller = MenuController::GetActiveInstance();
  30   DCHECK(menu_controller);
  31
  32   if (menu_controller->exit_type() == MenuController::EXIT_ALL ||
  33       menu_controller->exit_type() == MenuController::EXIT_DESTROYED) {
  34     // If the event has arrived after the menu's exit type had changed but
  35     // before its message loop terminated, the event will continue its normal
  36     // propagation for the following reason:
  37     // If the user accepts a menu item in a nested menu, the menu item action is
  38     // run after the base::RunLoop for the innermost menu has quit but before
  39     // the base::RunLoop for the outermost menu has quit. If the menu item
  40     // action starts a base::RunLoop, the outermost menu's base::RunLoop will
  41     // not quit till the action's base::RunLoop ends. IDC_BOOKMARK_BAR_OPEN_ALL
  42     // sometimes opens a modal dialog. The modal dialog starts a base::RunLoop
  43     // and keeps the base::RunLoop running for the duration of its lifetime.
  44     menu_controller->TerminateNestedMessageLoop();
  45     return;
  46   }
  47
  48   if (event->type() == ui::ET_KEY_PRESSED) {
  49     menu_controller->OnKeyDown(event->key_code());
  50
  51     // Do not check mnemonics if the Alt or Ctrl modifiers are pressed. For
  52     // example Ctrl+<T> is an accelerator, but <T> only is a mnemonic.
  53     const int flags = event->flags();
  54     if (menu_controller->exit_type() == MenuController::EXIT_NONE &&
  55         (flags & kKeyFlagsMask) == 0) {
  56       char c = ui::DomCodeToUsLayoutCharacter(event->code(), flags);
  57       menu_controller->SelectByChar(c);
  58     }
  59   }
  60
  61   if (menu_controller->exit_type() != MenuController::EXIT_NONE) {
  62     menu_controller->TerminateNestedMessageLoop();
  63   } else {
  64     ui::Accelerator accelerator(*event);
  65     ViewsDelegate::ProcessMenuAcceleratorResult result =
  66         ViewsDelegate::GetInstance()->ProcessAcceleratorWhileMenuShowing(
  67             accelerator);
  68     if (result == ViewsDelegate::ProcessMenuAcceleratorResult::CLOSE_MENU)
  69       menu_controller->CancelAll();
  70   }
  71
  72   event->StopPropagation();
  73 }
  74
  75 }  // namespace views