C++ VisibleSelection::isCaret方法代码示例

static bool isTextWithCaret(AccessibilityObject* coreObject)
{
    if (!coreObject || !coreObject->isAccessibilityRenderObject())
        return false;

    Document* document = coreObject->document();
    if (!document)
        return false;

    Frame* frame = document->frame();
    if (!frame)
        return false;

    if (!frame->settings().caretBrowsingEnabled())
        return false;

    // Check text objects and paragraphs only.
    AtkObject* axObject = coreObject->wrapper();
    AtkRole role = axObject ? atk_object_get_role(axObject) : ATK_ROLE_INVALID;
    if (role != ATK_ROLE_TEXT && role != ATK_ROLE_PARAGRAPH)
        return false;

    // Finally, check whether the caret is set in the current object.
    VisibleSelection selection = coreObject->selection();
    if (!selection.isCaret())
        return false;

    return selectionBelongsToObject(coreObject, selection);
}

static String selectMisspellingAsync(Frame* selectedFrame, DocumentMarker& marker)
{
    VisibleSelection selection = selectedFrame->selection()->selection();
    if (!selection.isCaretOrRange())
        return String();

    // Caret and range selections always return valid normalized ranges.
    RefPtr<Range> selectionRange = selection.toNormalizedRange();
    Vector<DocumentMarker*> markers = selectedFrame->document()->markers()->markersInRange(selectionRange.get(), DocumentMarker::Spelling | DocumentMarker::Grammar);
    if (markers.size() != 1)
        return String();
    marker = *markers[0];

    // Cloning a range fails only for invalid ranges.
    RefPtr<Range> markerRange = selectionRange->cloneRange(ASSERT_NO_EXCEPTION);
    markerRange->setStart(markerRange->startContainer(), marker.startOffset());
    markerRange->setEnd(markerRange->endContainer(), marker.endOffset());
    if (selection.isCaret()) {
        selection = VisibleSelection(markerRange.get());
        selectedFrame->selection()->setSelection(selection, WordGranularity);
        selectionRange = selection.toNormalizedRange();
    }

    if (markerRange->text().stripWhiteSpace(&IsWhiteSpaceOrPunctuation) != selectionRange->text().stripWhiteSpace(&IsWhiteSpaceOrPunctuation))
        return String();

    return markerRange->text();
}

static void writeSelection(TextStream& ts, const RenderObject* o)
{
    Node* n = o->node();
    if (!n || !n->isDocumentNode())
        return;

    Document* doc = static_cast<Document*>(n);
    Frame* frame = doc->frame();
    if (!frame)
        return;

    VisibleSelection selection = frame->selection()->selection();
    if (selection.isCaret()) {
        ts << "caret: position " << selection.start().deprecatedEditingOffset() << " of " << nodePosition(selection.start().node());
        if (selection.affinity() == UPSTREAM)
            ts << " (upstream affinity)";
        ts << "\n";
    } else if (selection.isRange())
        ts << "selection start: position " << selection.start().deprecatedEditingOffset() << " of " << nodePosition(selection.start().node()) << "\n"
           << "selection end:   position " << selection.end().deprecatedEditingOffset() << " of " << nodePosition(selection.end().node()) << "\n";
}

void Editor::transpose()
{
    if (!canEdit())
        return;

    VisibleSelection selection = m_frame.selection().selection();
    if (!selection.isCaret())
        return;

    // Make a selection that goes back one character and forward two characters.
    VisiblePosition caret = selection.visibleStart();
    VisiblePosition next = isEndOfParagraph(caret) ? caret : caret.next();
    VisiblePosition previous = next.previous();
    if (next == previous)
        return;
    previous = previous.previous();
    if (!inSameParagraph(next, previous))
        return;
    RefPtr<Range> range = makeRange(previous, next);
    if (!range)
        return;
    VisibleSelection newSelection(range.get(), DOWNSTREAM);

    // Transpose the two characters.
    String text = plainText(range.get());
    if (text.length() != 2)
        return;
    String transposed = text.right(1) + text.left(1);

    // Select the two characters.
    if (newSelection != m_frame.selection().selection())
        m_frame.selection().setSelection(newSelection);

    // Insert the transposed characters.
    replaceSelectionWithText(transposed, false, false);
}

Position adjustedSelectionStartForStyleComputation(const VisibleSelection& selection)
{
    // This function is used by range style computations to avoid bugs like:
    // <rdar://problem/4017641> REGRESSION (Mail): you can only bold/unbold a selection starting from end of line once
    // It is important to skip certain irrelevant content at the start of the selection, so we do not wind up 
    // with a spurious "mixed" style.

    VisiblePosition visiblePosition = selection.start();
    if (visiblePosition.isNull())
        return Position();

    // if the selection is a caret, just return the position, since the style
    // behind us is relevant
    if (selection.isCaret())
        return visiblePosition.deepEquivalent();

    // if the selection starts just before a paragraph break, skip over it
    if (isEndOfParagraph(visiblePosition))
        return visiblePosition.next().deepEquivalent().downstream();

    // otherwise, make sure to be at the start of the first selected node,
    // instead of possibly at the end of the last node before the selection
    return visiblePosition.deepEquivalent().downstream();
}

void TypingCommand::forwardDeleteKeyPressed(TextGranularity granularity, bool killRing)
{
    Frame* frame = document()->frame();
    if (!frame)
        return;

    frame->editor()->updateMarkersForWordsAffectedByEditing(false);

    VisibleSelection selectionToDelete;
    VisibleSelection selectionAfterUndo;

    switch (endingSelection().selectionType()) {
    case VisibleSelection::RangeSelection:
        selectionToDelete = endingSelection();
        selectionAfterUndo = selectionToDelete;
        break;
    case VisibleSelection::CaretSelection: {
        m_smartDelete = false;

        // Handle delete at beginning-of-block case.
        // Do nothing in the case that the caret is at the start of a
        // root editable element or at the start of a document.
        FrameSelection selection;
        selection.setSelection(endingSelection());
        selection.modify(FrameSelection::AlterationExtend, DirectionForward, granularity);
        if (killRing && selection.isCaret() && granularity != CharacterGranularity)
            selection.modify(FrameSelection::AlterationExtend, DirectionForward, CharacterGranularity);

        Position downstreamEnd = endingSelection().end().downstream();
        VisiblePosition visibleEnd = endingSelection().visibleEnd();
        Node* enclosingTableCell = enclosingNodeOfType(visibleEnd.deepEquivalent(), &isTableCell);
        if (enclosingTableCell && visibleEnd == lastPositionInNode(enclosingTableCell))
            return;
        if (visibleEnd == endOfParagraph(visibleEnd))
            downstreamEnd = visibleEnd.next(CannotCrossEditingBoundary).deepEquivalent().downstream();
        // When deleting tables: Select the table first, then perform the deletion
        if (downstreamEnd.containerNode() && downstreamEnd.containerNode()->renderer() && downstreamEnd.containerNode()->renderer()->isTable()
            && downstreamEnd.computeOffsetInContainerNode() <= caretMinOffset(downstreamEnd.containerNode())) {
            setEndingSelection(VisibleSelection(endingSelection().end(), positionAfterNode(downstreamEnd.containerNode()), DOWNSTREAM, endingSelection().isDirectional()));
            typingAddedToOpenCommand(ForwardDeleteKey);
            return;
        }

        // deleting to end of paragraph when at end of paragraph needs to merge the next paragraph (if any)
        if (granularity == ParagraphBoundary && selection.selection().isCaret() && isEndOfParagraph(selection.selection().visibleEnd()))
            selection.modify(FrameSelection::AlterationExtend, DirectionForward, CharacterGranularity);

        selectionToDelete = selection.selection();
        if (!startingSelection().isRange() || selectionToDelete.base() != startingSelection().start())
            selectionAfterUndo = selectionToDelete;
        else {
            // It's a little tricky to compute what the starting selection would have been in the original document.
            // We can't let the VisibleSelection class's validation kick in or it'll adjust for us based on
            // the current state of the document and we'll get the wrong result.
            Position extent = startingSelection().end();
            if (extent.containerNode() != selectionToDelete.end().containerNode())
                extent = selectionToDelete.extent();
            else {
                int extraCharacters;
                if (selectionToDelete.start().containerNode() == selectionToDelete.end().containerNode())
                    extraCharacters = selectionToDelete.end().computeOffsetInContainerNode() - selectionToDelete.start().computeOffsetInContainerNode();
                else
                    extraCharacters = selectionToDelete.end().computeOffsetInContainerNode();
                extent = Position(extent.containerNode(), extent.computeOffsetInContainerNode() + extraCharacters, Position::PositionIsOffsetInAnchor);
            }
            selectionAfterUndo.setWithoutValidation(startingSelection().start(), extent);
        }
        break;
    }
    case VisibleSelection::NoSelection:
        ASSERT_NOT_REACHED();
        break;
    }
    
    ASSERT(!selectionToDelete.isNone());
    if (selectionToDelete.isNone())
        return;
    
    if (selectionToDelete.isCaret() || !frame->selection()->shouldDeleteSelection(selectionToDelete))
        return;
        
    if (killRing)
        frame->editor()->addToKillRing(selectionToDelete.toNormalizedRange().get(), false);
    // make undo select what was deleted
    setStartingSelection(selectionAfterUndo);
    CompositeEditCommand::deleteSelection(selectionToDelete, m_smartDelete);
    setSmartDelete(false);
    typingAddedToOpenCommand(ForwardDeleteKey);
}

void TypingCommand::deleteKeyPressed(TextGranularity granularity, bool killRing)
{
    Frame* frame = document()->frame();
    if (!frame)
        return;

    frame->editor()->updateMarkersForWordsAffectedByEditing(false);

    VisibleSelection selectionToDelete;
    VisibleSelection selectionAfterUndo;

    switch (endingSelection().selectionType()) {
    case VisibleSelection::RangeSelection:
        selectionToDelete = endingSelection();
        selectionAfterUndo = selectionToDelete;
        break;
    case VisibleSelection::CaretSelection: {
        // After breaking out of an empty mail blockquote, we still want continue with the deletion
        // so actual content will get deleted, and not just the quote style.
        if (breakOutOfEmptyMailBlockquotedParagraph())
            typingAddedToOpenCommand(DeleteKey);

        m_smartDelete = false;

        FrameSelection selection;
        selection.setSelection(endingSelection());
        selection.modify(FrameSelection::AlterationExtend, DirectionBackward, granularity);
        if (killRing && selection.isCaret() && granularity != CharacterGranularity)
            selection.modify(FrameSelection::AlterationExtend, DirectionBackward, CharacterGranularity);

        if (endingSelection().visibleStart().previous(CannotCrossEditingBoundary).isNull()) {
            // When the caret is at the start of the editable area in an empty list item, break out of the list item.
            if (breakOutOfEmptyListItem()) {
                typingAddedToOpenCommand(DeleteKey);
                return;
            }
            // When there are no visible positions in the editing root, delete its entire contents.
            if (endingSelection().visibleStart().next(CannotCrossEditingBoundary).isNull() && makeEditableRootEmpty()) {
                typingAddedToOpenCommand(DeleteKey);
                return;
            }
        }

        VisiblePosition visibleStart(endingSelection().visibleStart());
        // If we have a caret selection at the beginning of a cell, we have nothing to do.
        Node* enclosingTableCell = enclosingNodeOfType(visibleStart.deepEquivalent(), &isTableCell);
        if (enclosingTableCell && visibleStart == firstPositionInNode(enclosingTableCell))
            return;

        // If the caret is at the start of a paragraph after a table, move content into the last table cell.
        if (isStartOfParagraph(visibleStart) && isFirstPositionAfterTable(visibleStart.previous(CannotCrossEditingBoundary))) {
            // Unless the caret is just before a table.  We don't want to move a table into the last table cell.
            if (isLastPositionBeforeTable(visibleStart))
                return;
            // Extend the selection backward into the last cell, then deletion will handle the move.
            selection.modify(FrameSelection::AlterationExtend, DirectionBackward, granularity);
        // If the caret is just after a table, select the table and don't delete anything.
        } else if (Node* table = isFirstPositionAfterTable(visibleStart)) {
            setEndingSelection(VisibleSelection(positionBeforeNode(table), endingSelection().start(), DOWNSTREAM, endingSelection().isDirectional()));
            typingAddedToOpenCommand(DeleteKey);
            return;
        }

        selectionToDelete = selection.selection();

        if (granularity == CharacterGranularity && selectionToDelete.end().containerNode() == selectionToDelete.start().containerNode()
            && selectionToDelete.end().computeOffsetInContainerNode() - selectionToDelete.start().computeOffsetInContainerNode() > 1) {
            // If there are multiple Unicode code points to be deleted, adjust the range to match platform conventions.
            selectionToDelete.setWithoutValidation(selectionToDelete.end(), selectionToDelete.end().previous(BackwardDeletion));
        }

        if (!startingSelection().isRange() || selectionToDelete.base() != startingSelection().start())
            selectionAfterUndo = selectionToDelete;
        else
            // It's a little tricky to compute what the starting selection would have been in the original document.
            // We can't let the VisibleSelection class's validation kick in or it'll adjust for us based on
            // the current state of the document and we'll get the wrong result.
            selectionAfterUndo.setWithoutValidation(startingSelection().end(), selectionToDelete.extent());
        break;
    }
    case VisibleSelection::NoSelection:
        ASSERT_NOT_REACHED();
        break;
    }
    
    ASSERT(!selectionToDelete.isNone());
    if (selectionToDelete.isNone())
        return;
    
    if (selectionToDelete.isCaret() || !frame->selection()->shouldDeleteSelection(selectionToDelete))
        return;
    
    if (killRing)
        frame->editor()->addToKillRing(selectionToDelete.toNormalizedRange().get(), false);
    // Make undo select everything that has been deleted, unless an undo will undo more than just this deletion.
    // FIXME: This behaves like TextEdit except for the case where you open with text insertion and then delete
    // more text than you insert.  In that case all of the text that was around originally should be selected.
    if (m_openedByBackwardDelete)
        setStartingSelection(selectionAfterUndo);
    CompositeEditCommand::deleteSelection(selectionToDelete, m_smartDelete);
//.........这里部分代码省略.........

void TypingCommand::forwardDeleteKeyPressed(TextGranularity granularity, bool killRing)
{
    VisibleSelection selectionToDelete;
    VisibleSelection selectionAfterUndo;

    switch (endingSelection().selectionType()) {
        case VisibleSelection::RangeSelection:
            selectionToDelete = endingSelection();
            selectionAfterUndo = selectionToDelete;
            break;
        case VisibleSelection::CaretSelection: {
            m_smartDelete = false;

            // Handle delete at beginning-of-block case.
            // Do nothing in the case that the caret is at the start of a
            // root editable element or at the start of a document.
            SelectionController selection;
            selection.setSelection(endingSelection());
            selection.modify(SelectionController::EXTEND, SelectionController::FORWARD, granularity);
            if (killRing && selection.isCaret() && granularity != CharacterGranularity) 
                selection.modify(SelectionController::EXTEND, SelectionController::FORWARD, CharacterGranularity); 
            
            Position downstreamEnd = endingSelection().end().downstream();
            VisiblePosition visibleEnd = endingSelection().visibleEnd();
            if (visibleEnd == endOfParagraph(visibleEnd))
                downstreamEnd = visibleEnd.next(true).deepEquivalent().downstream();
            // When deleting tables: Select the table first, then perform the deletion
            if (downstreamEnd.node() && downstreamEnd.node()->renderer() && downstreamEnd.node()->renderer()->isTable() && downstreamEnd.deprecatedEditingOffset() == 0) {
                setEndingSelection(VisibleSelection(endingSelection().end(), lastDeepEditingPositionForNode(downstreamEnd.node()), DOWNSTREAM));
                typingAddedToOpenCommand(ForwardDeleteKey);
                return;
            }

            // deleting to end of paragraph when at end of paragraph needs to merge the next paragraph (if any)
            if (granularity == ParagraphBoundary && selection.selection().isCaret() && isEndOfParagraph(selection.selection().visibleEnd()))
                selection.modify(SelectionController::EXTEND, SelectionController::FORWARD, CharacterGranularity);

            selectionToDelete = selection.selection();
            if (!startingSelection().isRange() || selectionToDelete.base() != startingSelection().start())
                selectionAfterUndo = selectionToDelete;
            else {
                // It's a little tricky to compute what the starting selection would have been in the original document.
                // We can't let the VisibleSelection class's validation kick in or it'll adjust for us based on
                // the current state of the document and we'll get the wrong result.
                Position extent = startingSelection().end();
                if (extent.node() != selectionToDelete.end().node())
                    extent = selectionToDelete.extent();
                else {
                    int extraCharacters;
                    if (selectionToDelete.start().node() == selectionToDelete.end().node())
                        extraCharacters = selectionToDelete.end().deprecatedEditingOffset() - selectionToDelete.start().deprecatedEditingOffset();
                    else
                        extraCharacters = selectionToDelete.end().deprecatedEditingOffset();
                    extent = Position(extent.node(), extent.deprecatedEditingOffset() + extraCharacters);
                }
                selectionAfterUndo.setWithoutValidation(startingSelection().start(), extent);
            }
            break;
        }
        case VisibleSelection::NoSelection:
            ASSERT_NOT_REACHED();
            break;
    }
    
    ASSERT(!selectionToDelete.isNone());
    if (selectionToDelete.isNone())
        return;
    
    if (selectionToDelete.isCaret() || !document()->frame()->shouldDeleteSelection(selectionToDelete))
        return;
        
    if (killRing)
        document()->frame()->editor()->addToKillRing(selectionToDelete.toNormalizedRange().get(), false);
    // make undo select what was deleted
    setStartingSelection(selectionAfterUndo);
    CompositeEditCommand::deleteSelection(selectionToDelete, m_smartDelete);
    setSmartDelete(false);
    typingAddedToOpenCommand(ForwardDeleteKey);
}

//.........这里部分代码省略.........

    // If it's not a link, an image, a media element, or an image/media link,
    // show a selection menu or a more generic page menu.
    if (selectedFrame->document()->loader())
        data.frameEncoding = selectedFrame->document()->encoding();

    // Send the frame and page URLs in any case.
    data.pageURL = urlFromFrame(m_webView->mainFrameImpl()->frame());
    if (selectedFrame != m_webView->mainFrameImpl()->frame()) {
        data.frameURL = urlFromFrame(selectedFrame);
        RefPtr<HistoryItem> historyItem = selectedFrame->loader()->history()->currentItem();
        if (historyItem)
            data.frameHistoryItem = WebHistoryItem(historyItem);
    }

    if (r.isSelected()) {
        if (!r.innerNonSharedNode()->hasTagName(HTMLNames::inputTag) || !static_cast<HTMLInputElement*>(r.innerNonSharedNode())->isPasswordField())
            data.selectedText = selectedFrame->editor()->selectedText().stripWhiteSpace();
    }

    if (r.isContentEditable()) {
        data.isEditable = true;
#if ENABLE(INPUT_SPEECH)
        if (r.innerNonSharedNode()->hasTagName(HTMLNames::inputTag)) {
            data.isSpeechInputEnabled = 
                static_cast<HTMLInputElement*>(r.innerNonSharedNode())->isSpeechEnabled();
        }  
#endif
        // When Chrome enables asynchronous spellchecking, its spellchecker adds spelling markers to misspelled
        // words and attaches suggestions to these markers in the background. Therefore, when a user right-clicks
        // a mouse on a word, Chrome just needs to find a spelling marker on the word instread of spellchecking it.
        if (selectedFrame->settings() && selectedFrame->settings()->asynchronousSpellCheckingEnabled()) {
            VisibleSelection selection = selectedFrame->selection()->selection();
            if (selection.isCaret()) {
                selection.expandUsingGranularity(WordGranularity);
                RefPtr<Range> range = selection.toNormalizedRange();
                Vector<DocumentMarker*> markers = selectedFrame->document()->markers()->markersInRange(range.get(), DocumentMarker::Spelling | DocumentMarker::Grammar);
                if (markers.size() == 1) {
                    range->setStart(range->startContainer(), markers[0]->startOffset());
                    range->setEnd(range->endContainer(), markers[0]->endOffset());
                    data.misspelledWord = range->text();
                    if (markers[0]->description().length()) {
                        Vector<String> suggestions;
                        markers[0]->description().split('\n', suggestions);
                        data.dictionarySuggestions = suggestions;
                    } else if (m_webView->spellCheckClient()) {
                        int misspelledOffset, misspelledLength;
                        m_webView->spellCheckClient()->spellCheck(data.misspelledWord, misspelledOffset, misspelledLength, &data.dictionarySuggestions);
                    }
                    selection = VisibleSelection(range.get());
                    if (selectedFrame->selection()->shouldChangeSelection(selection))
                        selectedFrame->selection()->setSelection(selection, WordGranularity);
                }
            }
        } else if (m_webView->focusedWebCoreFrame()->editor()->isContinuousSpellCheckingEnabled()) {
            data.isSpellCheckingEnabled = true;
            // Spellchecking might be enabled for the field, but could be disabled on the node.
            if (m_webView->focusedWebCoreFrame()->editor()->isSpellCheckingEnabledInFocusedNode()) {
                data.misspelledWord = selectMisspelledWord(defaultMenu, selectedFrame);
                if (m_webView->spellCheckClient()) {
                    int misspelledOffset, misspelledLength;
                    m_webView->spellCheckClient()->spellCheck(
                        data.misspelledWord, misspelledOffset, misspelledLength,
                        &data.dictionarySuggestions);
                    if (!misspelledLength)
                        data.misspelledWord.reset();