accessible/base/SelectionManager.cpp

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "mozilla/a11y/SelectionManager.h"
   7
   8 #include "DocAccessible-inl.h"
   9 #include "HyperTextAccessible.h"
  10 #include "HyperTextAccessible-inl.h"
  11 #include "nsAccUtils.h"
  12 #include "nsCoreUtils.h"
  13 #include "nsEventShell.h"
  14 #include "nsFrameSelection.h"
  15 #include "TextLeafRange.h"
  16
  17 #include "mozilla/PresShell.h"
  18 #include "mozilla/dom/Selection.h"
  19 #include "mozilla/dom/Element.h"
  20
  21 using namespace mozilla;
  22 using namespace mozilla::a11y;
  23 using mozilla::dom::Selection;
  24
  25 struct mozilla::a11y::SelData final {
  26   SelData(Selection* aSel, int32_t aReason, int32_t aGranularity)
  27       : mSel(aSel), mReason(aReason), mGranularity(aGranularity) {}
  28
  29   RefPtr<Selection> mSel;
  30   int16_t mReason;
  31   int32_t mGranularity;
  32
  33   NS_INLINE_DECL_REFCOUNTING(SelData)
  34
  35  private:
  36   // Private destructor, to discourage deletion outside of Release():
  37   ~SelData() {}
  38 };
  39
  40 SelectionManager::SelectionManager()
  41     : mCaretOffset(-1), mAccWithCaret(nullptr) {}
  42
  43 void SelectionManager::ClearControlSelectionListener() {
  44   // Remove 'this' registered as selection listener for the normal selection.
  45   if (mCurrCtrlNormalSel) {
  46     mCurrCtrlNormalSel->RemoveSelectionListener(this);
  47     mCurrCtrlNormalSel = nullptr;
  48   }
  49
  50   // Remove 'this' registered as selection listener for the spellcheck
  51   // selection.
  52   if (mCurrCtrlSpellSel) {
  53     mCurrCtrlSpellSel->RemoveSelectionListener(this);
  54     mCurrCtrlSpellSel = nullptr;
  55   }
  56 }
  57
  58 void SelectionManager::SetControlSelectionListener(dom::Element* aFocusedElm) {
  59   // When focus moves such that the caret is part of a new frame selection
  60   // this removes the old selection listener and attaches a new one for
  61   // the current focus.
  62   ClearControlSelectionListener();
  63
  64   nsIFrame* controlFrame = aFocusedElm->GetPrimaryFrame();
  65   if (!controlFrame) return;
  66
  67   const nsFrameSelection* frameSel = controlFrame->GetConstFrameSelection();
  68   NS_ASSERTION(frameSel, "No frame selection for focused element!");
  69   if (!frameSel) return;
  70
  71   // Register 'this' as selection listener for the normal selection.
  72   Selection* normalSel = frameSel->GetSelection(SelectionType::eNormal);
  73   normalSel->AddSelectionListener(this);
  74   mCurrCtrlNormalSel = normalSel;
  75
  76   // Register 'this' as selection listener for the spell check selection.
  77   Selection* spellSel = frameSel->GetSelection(SelectionType::eSpellCheck);
  78   spellSel->AddSelectionListener(this);
  79   mCurrCtrlSpellSel = spellSel;
  80 }
  81
  82 void SelectionManager::AddDocSelectionListener(PresShell* aPresShell) {
  83   const nsFrameSelection* frameSel = aPresShell->ConstFrameSelection();
  84
  85   // Register 'this' as selection listener for the normal selection.
  86   Selection* normalSel = frameSel->GetSelection(SelectionType::eNormal);
  87   normalSel->AddSelectionListener(this);
  88
  89   // Register 'this' as selection listener for the spell check selection.
  90   Selection* spellSel = frameSel->GetSelection(SelectionType::eSpellCheck);
  91   spellSel->AddSelectionListener(this);
  92 }
  93
  94 void SelectionManager::RemoveDocSelectionListener(PresShell* aPresShell) {
  95   const nsFrameSelection* frameSel = aPresShell->ConstFrameSelection();
  96
  97   // Remove 'this' registered as selection listener for the normal selection.
  98   Selection* normalSel = frameSel->GetSelection(SelectionType::eNormal);
  99   normalSel->RemoveSelectionListener(this);
 100
 101   // Remove 'this' registered as selection listener for the spellcheck
 102   // selection.
 103   Selection* spellSel = frameSel->GetSelection(SelectionType::eSpellCheck);
 104   spellSel->RemoveSelectionListener(this);
 105
 106   if (mCurrCtrlNormalSel) {
 107     if (mCurrCtrlNormalSel->GetPresShell() == aPresShell) {
 108       // Remove 'this' registered as selection listener for the normal selection
 109       // if we are removing listeners for its PresShell.
 110       mCurrCtrlNormalSel->RemoveSelectionListener(this);
 111       mCurrCtrlNormalSel = nullptr;
 112     }
 113   }
 114
 115   if (mCurrCtrlSpellSel) {
 116     if (mCurrCtrlSpellSel->GetPresShell() == aPresShell) {
 117       // Remove 'this' registered as selection listener for the spellcheck
 118       // selection if we are removing listeners for its PresShell.
 119       mCurrCtrlSpellSel->RemoveSelectionListener(this);
 120       mCurrCtrlSpellSel = nullptr;
 121     }
 122   }
 123 }
 124
 125 void SelectionManager::ProcessTextSelChangeEvent(AccEvent* aEvent) {
 126   // Fire selection change event if it's not pure caret-move selection change,
 127   // i.e. the accessible has or had not collapsed selection. Also, it must not
 128   // be a collapsed selection on the container of a focused text field, since
 129   // the text field has an independent selection and will thus fire its own
 130   // selection events.
 131   AccTextSelChangeEvent* event = downcast_accEvent(aEvent);
 132   if (!event->IsCaretMoveOnly() &&
 133       !(event->mSel->IsCollapsed() && event->mSel != mCurrCtrlNormalSel &&
 134         FocusMgr() && FocusMgr()->FocusedLocalAccessible() &&
 135         FocusMgr()->FocusedLocalAccessible()->IsTextField())) {
 136     nsEventShell::FireEvent(aEvent);
 137   }
 138
 139   // Fire caret move event if there's a caret in the selection.
 140   nsINode* caretCntrNode = nsCoreUtils::GetDOMNodeFromDOMPoint(
 141       event->mSel->GetFocusNode(), event->mSel->FocusOffset());
 142   if (!caretCntrNode) return;
 143
 144   HyperTextAccessible* caretCntr = nsAccUtils::GetTextContainer(caretCntrNode);
 145   NS_ASSERTION(
 146       caretCntr,
 147       "No text container for focus while there's one for common ancestor?!");
 148   if (!caretCntr) return;
 149
 150   Selection* selection = caretCntr->DOMSelection();
 151
 152   // XXX Sometimes we can't get a selection for caretCntr, in that case assume
 153   // event->mSel is correct.
 154   if (!selection) selection = event->mSel;
 155
 156   mCaretOffset = caretCntr->DOMPointToOffset(selection->GetFocusNode(),
 157                                              selection->FocusOffset());
 158   mAccWithCaret = caretCntr;
 159   if (mCaretOffset != -1) {
 160     RefPtr<AccCaretMoveEvent> caretMoveEvent =
 161         new AccCaretMoveEvent(caretCntr, mCaretOffset, selection->IsCollapsed(),
 162                               caretCntr->IsCaretAtEndOfLine(),
 163                               event->GetGranularity(), aEvent->FromUserInput());
 164     nsEventShell::FireEvent(caretMoveEvent);
 165   }
 166 }
 167
 168 NS_IMETHODIMP
 169 SelectionManager::NotifySelectionChanged(dom::Document* aDocument,
 170                                          Selection* aSelection, int16_t aReason,
 171                                          int32_t aAmount) {
 172   if (NS_WARN_IF(!aDocument) || NS_WARN_IF(!aSelection)) {
 173     return NS_ERROR_INVALID_ARG;
 174   }
 175
 176   DocAccessible* document = GetAccService()->GetDocAccessible(aDocument);
 177
 178 #ifdef A11Y_LOG
 179   if (logging::IsEnabled(logging::eSelection)) {
 180     logging::SelChange(aSelection, document, aReason);
 181   }
 182 #endif
 183
 184   if (document) {
 185     // Selection manager has longer lifetime than any document accessible,
 186     // so that we are guaranteed that the notification is processed before
 187     // the selection manager is destroyed.
 188     RefPtr<SelData> selData = new SelData(aSelection, aReason, aAmount);
 189     document->HandleNotification<SelectionManager, SelData>(
 190         this, &SelectionManager::ProcessSelectionChanged, selData);
 191   }
 192
 193   return NS_OK;
 194 }
 195
 196 void SelectionManager::ProcessSelectionChanged(SelData* aSelData) {
 197   Selection* selection = aSelData->mSel;
 198   if (!selection->GetPresShell()) return;
 199
 200   const nsRange* range = selection->GetAnchorFocusRange();
 201   nsINode* cntrNode = nullptr;
 202   if (range) {
 203     cntrNode = range->GetClosestCommonInclusiveAncestor();
 204   }
 205
 206   if (!cntrNode) {
 207     cntrNode = selection->GetFrameSelection()->GetAncestorLimiter();
 208     if (!cntrNode) {
 209       cntrNode = selection->GetPresShell()->GetDocument();
 210       NS_ASSERTION(aSelData->mSel->GetPresShell()->ConstFrameSelection() ==
 211                        selection->GetFrameSelection(),
 212                    "Wrong selection container was used!");
 213     }
 214   }
 215
 216   HyperTextAccessible* text = nsAccUtils::GetTextContainer(cntrNode);
 217   if (!text) {
 218     // FIXME bug 1126649
 219     NS_ERROR("We must reach document accessible implementing text interface!");
 220     return;
 221   }
 222
 223   if (selection->GetType() == SelectionType::eNormal) {
 224     RefPtr<AccEvent> event = new AccTextSelChangeEvent(
 225         text, selection, aSelData->mReason, aSelData->mGranularity);
 226     text->Document()->FireDelayedEvent(event);
 227
 228   } else if (selection->GetType() == SelectionType::eSpellCheck) {
 229     // XXX: fire an event for container accessible of the focus/anchor range
 230     // of the spelcheck selection.
 231     text->Document()->FireDelayedEvent(
 232         nsIAccessibleEvent::EVENT_TEXT_ATTRIBUTE_CHANGED, text);
 233   }
 234 }
 235
 236 void SelectionManager::SpellCheckRangeChanged(const nsRange& aRange) {
 237   // Events are fired in SelectionManager::NotifySelectionChanged. This is only
 238   // used to push cache updates.
 239   if (IPCAccessibilityActive()) {
 240     dom::Document* doc = aRange.GetStartContainer()->OwnerDoc();
 241     MOZ_ASSERT(doc);
 242     TextLeafPoint::UpdateCachedSpellingError(doc, aRange);
 243   }
 244 }
 245
 246 SelectionManager::~SelectionManager() = default;