views/accelerator.cc

   1 // Copyright (c) 2011 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 "views/accelerator.h"
   6
   7 #if defined(OS_WIN)
   8 #include <windows.h>
   9 #elif defined(TOOLKIT_USES_GTK)
  10 #include <gdk/gdk.h>
  11 #endif
  12
  13 #include "base/i18n/rtl.h"
  14 #include "base/logging.h"
  15 #include "base/string_util.h"
  16 #include "base/utf_string_conversions.h"
  17 #include "grit/ui_strings.h"
  18 #include "ui/base/l10n/l10n_util.h"
  19
  20 namespace views {
  21
  22 string16 Accelerator::GetShortcutText() const {
  23   int string_id = 0;
  24   switch(key_code_) {
  25     case ui::VKEY_TAB:
  26       string_id = IDS_APP_TAB_KEY;
  27       break;
  28     case ui::VKEY_RETURN:
  29       string_id = IDS_APP_ENTER_KEY;
  30       break;
  31     case ui::VKEY_ESCAPE:
  32       string_id = IDS_APP_ESC_KEY;
  33       break;
  34     case ui::VKEY_PRIOR:
  35       string_id = IDS_APP_PAGEUP_KEY;
  36       break;
  37     case ui::VKEY_NEXT:
  38       string_id = IDS_APP_PAGEDOWN_KEY;
  39       break;
  40     case ui::VKEY_END:
  41       string_id = IDS_APP_END_KEY;
  42       break;
  43     case ui::VKEY_HOME:
  44       string_id = IDS_APP_HOME_KEY;
  45       break;
  46     case ui::VKEY_INSERT:
  47       string_id = IDS_APP_INSERT_KEY;
  48       break;
  49     case ui::VKEY_DELETE:
  50       string_id = IDS_APP_DELETE_KEY;
  51       break;
  52     case ui::VKEY_LEFT:
  53       string_id = IDS_APP_LEFT_ARROW_KEY;
  54       break;
  55     case ui::VKEY_RIGHT:
  56       string_id = IDS_APP_RIGHT_ARROW_KEY;
  57       break;
  58     case ui::VKEY_BACK:
  59       string_id = IDS_APP_BACKSPACE_KEY;
  60       break;
  61     case ui::VKEY_F1:
  62       string_id = IDS_APP_F1_KEY;
  63       break;
  64     case ui::VKEY_F11:
  65       string_id = IDS_APP_F11_KEY;
  66       break;
  67     default:
  68       break;
  69   }
  70
  71   string16 shortcut;
  72   if (!string_id) {
  73 #if defined(OS_WIN)
  74     // Our fallback is to try translate the key code to a regular character
  75     // unless it is one of digits (VK_0 to VK_9). Some keyboard
  76     // layouts have characters other than digits assigned in
  77     // an unshifted mode (e.g. French AZERY layout has 'a with grave
  78     // accent' for '0'). For display in the menu (e.g. Ctrl-0 for the
  79     // default zoom level), we leave VK_[0-9] alone without translation.
  80     wchar_t key;
  81     if (key_code_ >= '0' && key_code_ <= '9')
  82       key = key_code_;
  83     else
  84       key = LOWORD(::MapVirtualKeyW(key_code_, MAPVK_VK_TO_CHAR));
  85     shortcut += key;
  86 #elif defined(TOOLKIT_USES_GTK)
  87     const gchar* name = NULL;
  88     switch (key_code_) {
  89       case ui::VKEY_OEM_2:
  90         name = static_cast<const gchar*>("/");
  91         break;
  92       default:
  93         name = gdk_keyval_name(gdk_keyval_to_lower(key_code_));
  94         break;
  95     }
  96     if (name) {
  97       if (name[0] != 0 && name[1] == 0)
  98         shortcut += static_cast<string16::value_type>(g_ascii_toupper(name[0]));
  99       else
 100         shortcut += UTF8ToUTF16(name);
 101     }
 102 #endif
 103   } else {
 104     shortcut = l10n_util::GetStringUTF16(string_id);
 105   }
 106
 107   // Checking whether the character used for the accelerator is alphanumeric.
 108   // If it is not, then we need to adjust the string later on if the locale is
 109   // right-to-left. See below for more information of why such adjustment is
 110   // required.
 111   string16 shortcut_rtl;
 112   bool adjust_shortcut_for_rtl = false;
 113   if (base::i18n::IsRTL() && shortcut.length() == 1 &&
 114       !IsAsciiAlpha(shortcut[0]) && !IsAsciiDigit(shortcut[0])) {
 115     adjust_shortcut_for_rtl = true;
 116     shortcut_rtl.assign(shortcut);
 117   }
 118
 119   if (IsShiftDown())
 120     shortcut = l10n_util::GetStringFUTF16(IDS_APP_SHIFT_MODIFIER, shortcut);
 121
 122   // Note that we use 'else-if' in order to avoid using Ctrl+Alt as a shortcut.
 123   // See http://blogs.msdn.com/oldnewthing/archive/2004/03/29/101121.aspx for
 124   // more information.
 125   if (IsCtrlDown())
 126     shortcut = l10n_util::GetStringFUTF16(IDS_APP_CONTROL_MODIFIER, shortcut);
 127   else if (IsAltDown())
 128     shortcut = l10n_util::GetStringFUTF16(IDS_APP_ALT_MODIFIER, shortcut);
 129
 130   // For some reason, menus in Windows ignore standard Unicode directionality
 131   // marks (such as LRE, PDF, etc.). On RTL locales, we use RTL menus and
 132   // therefore any text we draw for the menu items is drawn in an RTL context.
 133   // Thus, the text "Ctrl++" (which we currently use for the Zoom In option)
 134   // appears as "++Ctrl" in RTL because the Unicode BiDi algorithm puts
 135   // punctuations on the left when the context is right-to-left. Shortcuts that
 136   // do not end with a punctuation mark (such as "Ctrl+H" do not have this
 137   // problem).
 138   //
 139   // The only way to solve this problem is to adjust the string if the locale
 140   // is RTL so that it is drawn correnctly in an RTL context. Instead of
 141   // returning "Ctrl++" in the above example, we return "++Ctrl". This will
 142   // cause the text to appear as "Ctrl++" when Windows draws the string in an
 143   // RTL context because the punctunation no longer appears at the end of the
 144   // string.
 145   //
 146   // TODO(idana) bug# 1232732: this hack can be avoided if instead of using
 147   // views::Menu we use views::MenuItemView because the latter is a View
 148   // subclass and therefore it supports marking text as RTL or LTR using
 149   // standard Unicode directionality marks.
 150   if (adjust_shortcut_for_rtl) {
 151     int key_length = static_cast<int>(shortcut_rtl.length());
 152     DCHECK_GT(key_length, 0);
 153     shortcut_rtl.append(ASCIIToUTF16("+"));
 154
 155     // Subtracting the size of the shortcut key and 1 for the '+' sign.
 156     shortcut_rtl.append(shortcut, 0, shortcut.length() - key_length - 1);
 157     shortcut.swap(shortcut_rtl);
 158   }
 159
 160   return shortcut;
 161 }
 162
 163 }  // namespace views