dom/events/ShortcutKeys.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "ShortcutKeys.h"
   8 #include "mozilla/KeyEventHandler.h"
   9 #include "nsContentUtils.h"
  10 #include "nsAtom.h"
  11 #include "mozilla/TextEvents.h"
  12
  13 namespace mozilla {
  14
  15 NS_IMPL_ISUPPORTS(ShortcutKeys, nsIObserver);
  16
  17 StaticRefPtr<ShortcutKeys> ShortcutKeys::sInstance;
  18
  19 ShortcutKeys::ShortcutKeys()
  20     : mBrowserHandlers(nullptr),
  21       mEditorHandlers(nullptr),
  22       mInputHandlers(nullptr),
  23       mTextAreaHandlers(nullptr) {
  24   MOZ_ASSERT(!sInstance, "Attempt to instantiate a second ShortcutKeys.");
  25   nsContentUtils::RegisterShutdownObserver(this);
  26 }
  27
  28 ShortcutKeys::~ShortcutKeys() {
  29   delete mBrowserHandlers;
  30   delete mEditorHandlers;
  31   delete mInputHandlers;
  32   delete mTextAreaHandlers;
  33 }
  34
  35 nsresult ShortcutKeys::Observe(nsISupports* aSubject, const char* aTopic,
  36                                const char16_t* aData) {
  37   // Clear our strong reference so we can clean up.
  38   ShortcutKeys::Shutdown();
  39   return NS_OK;
  40 }
  41
  42 void ShortcutKeys::Shutdown() { sInstance = nullptr; }
  43
  44 /* static */
  45 KeyEventHandler* ShortcutKeys::GetHandlers(HandlerType aType) {
  46   if (!sInstance) {
  47     sInstance = new ShortcutKeys();
  48   }
  49
  50   return sInstance->EnsureHandlers(aType);
  51 }
  52
  53 /* static */
  54 nsAtom* ShortcutKeys::ConvertEventToDOMEventType(
  55     const WidgetKeyboardEvent* aWidgetKeyboardEvent) {
  56   switch (aWidgetKeyboardEvent->mMessage) {
  57     case eKeyDown:
  58       return nsGkAtoms::keydown;
  59     case eKeyUp:
  60       return nsGkAtoms::keyup;
  61     // eAccessKeyNotFound event is always created from eKeyPress event and
  62     // the original eKeyPress event has stopped its propagation before
  63     // dispatched into the DOM tree in this process and not matched with remote
  64     // content's access keys.  So, we should treat it as an eKeyPress event and
  65     // execute a command if it's registered as a shortcut key.
  66     case eKeyPress:
  67     case eAccessKeyNotFound:
  68       return nsGkAtoms::keypress;
  69     default:
  70       MOZ_ASSERT_UNREACHABLE(
  71           "All event messages relating to shortcut keys should be handled");
  72       return nullptr;
  73   }
  74 }
  75
  76 KeyEventHandler* ShortcutKeys::EnsureHandlers(HandlerType aType) {
  77   ShortcutKeyData* keyData;
  78   KeyEventHandler** cache;
  79
  80   switch (aType) {
  81     case HandlerType::eBrowser:
  82       keyData = &sBrowserHandlers[0];
  83       cache = &mBrowserHandlers;
  84       break;
  85     case HandlerType::eEditor:
  86       keyData = &sEditorHandlers[0];
  87       cache = &mEditorHandlers;
  88       break;
  89     case HandlerType::eInput:
  90       keyData = &sInputHandlers[0];
  91       cache = &mInputHandlers;
  92       break;
  93     case HandlerType::eTextArea:
  94       keyData = &sTextAreaHandlers[0];
  95       cache = &mTextAreaHandlers;
  96       break;
  97     default:
  98       MOZ_ASSERT(false, "Unknown handler type requested.");
  99   }
 100
 101   if (*cache) {
 102     return *cache;
 103   }
 104
 105   KeyEventHandler* lastHandler = nullptr;
 106   while (keyData->event) {
 107     KeyEventHandler* handler = new KeyEventHandler(keyData);
 108     if (lastHandler) {
 109       lastHandler->SetNextHandler(handler);
 110     } else {
 111       *cache = handler;
 112     }
 113     lastHandler = handler;
 114     keyData++;
 115   }
 116
 117   return *cache;
 118 }
 119
 120 }  // namespace mozilla