C++ OwnPtrWillBeRawPtr::selection方法代码示例

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

    frame->spellChecker().updateMarkersForWordsAffectedByEditing(false);

    VisibleSelection selectionToDelete;
    VisibleSelection selectionAfterUndo;

    switch (endingSelection().selectionType()) {
    case RangeSelection:
        selectionToDelete = endingSelection();
        selectionAfterUndo = selectionToDelete;
        break;
    case 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;

        OwnPtrWillBeRawPtr<FrameSelection> selection = FrameSelection::create();
        selection->setSelection(endingSelection());
        selection->modify(FrameSelection::AlterationExtend, DirectionBackward, granularity);
        if (killRing && selection->isCaret() && granularity != CharacterGranularity)
            selection->modify(FrameSelection::AlterationExtend, DirectionBackward, CharacterGranularity);

        VisiblePosition visibleStart(endingSelection().visibleStart());
        if (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 (visibleStart.next(CannotCrossEditingBoundary).isNull() && makeEditableRootEmpty()) {
                typingAddedToOpenCommand(DeleteKey);
                return;
            }
        }

        // 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 == VisiblePosition(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 NoSelection:
        ASSERT_NOT_REACHED();
        break;
    }

    ASSERT(!selectionToDelete.isNone());
    if (selectionToDelete.isNone())
        return;

    if (selectionToDelete.isCaret())
        return;

    if (killRing)
        frame->editor().addToKillRing(selectionToDelete.toNormalizedRange().get(), false);
    // On Mac, 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 (frame->editor().behavior().shouldUndoOfDeleteSelectText() && m_openedByBackwardDelete)
        setStartingSelection(selectionAfterUndo);
    CompositeEditCommand::deleteSelection(selectionToDelete, m_smartDelete);
//.........这里部分代码省略.........

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

    frame->spellChecker().updateMarkersForWordsAffectedByEditing(false);

    VisibleSelection selectionToDelete;
    VisibleSelection selectionAfterUndo;

    switch (endingSelection().selectionType()) {
    case RangeSelection:
        selectionToDelete = endingSelection();
        selectionAfterUndo = selectionToDelete;
        break;
    case 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.
        OwnPtrWillBeRawPtr<FrameSelection> selection = FrameSelection::create();
        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 == VisiblePosition(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 (isRenderedTable(downstreamEnd.containerNode()) && 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 NoSelection:
        ASSERT_NOT_REACHED();
        break;
    }

    ASSERT(!selectionToDelete.isNone());
    if (selectionToDelete.isNone())
        return;

    if (selectionToDelete.isCaret())
        return;

    if (killRing)
        frame->editor().addToKillRing(selectionToDelete.toNormalizedRange().get(), false);
    // Make undo select what was deleted on Mac alone
    if (frame->editor().behavior().shouldUndoOfDeleteSelectText())
        setStartingSelection(selectionAfterUndo);
    CompositeEditCommand::deleteSelection(selectionToDelete, m_smartDelete);
    setSmartDelete(false);
    typingAddedToOpenCommand(ForwardDeleteKey);
}

bool SelectionEditor::modify(EAlteration alter, SelectionDirection direction, TextGranularity granularity, EUserTriggered userTriggered)
{
    if (userTriggered == UserTriggered) {
        OwnPtrWillBeRawPtr<FrameSelection> trialFrameSelection = FrameSelection::create();
        trialFrameSelection->setSelection(m_selection);
        trialFrameSelection->modify(alter, direction, granularity, NotUserTriggered);

        if (trialFrameSelection->selection().isRange() && m_selection.isCaret() && !dispatchSelectStart())
            return false;
    }

    willBeModified(alter, direction);

    bool wasRange = m_selection.isRange();
    VisiblePosition originalStartPosition = m_selection.visibleStart();
    VisiblePosition position;
    switch (direction) {
    case DirectionRight:
        if (alter == FrameSelection::AlterationMove)
            position = modifyMovingRight(granularity);
        else
            position = modifyExtendingRight(granularity);
        break;
    case DirectionForward:
        if (alter == FrameSelection::AlterationExtend)
            position = modifyExtendingForward(granularity);
        else
            position = modifyMovingForward(granularity);
        break;
    case DirectionLeft:
        if (alter == FrameSelection::AlterationMove)
            position = modifyMovingLeft(granularity);
        else
            position = modifyExtendingLeft(granularity);
        break;
    case DirectionBackward:
        if (alter == FrameSelection::AlterationExtend)
            position = modifyExtendingBackward(granularity);
        else
            position = modifyMovingBackward(granularity);
        break;
    }

    if (position.isNull())
        return false;

    if (isSpatialNavigationEnabled(frame())) {
        if (!wasRange && alter == FrameSelection::AlterationMove && position.deepEquivalent() == originalStartPosition.deepEquivalent())
            return false;
    }

    // Some of the above operations set an xPosForVerticalArrowNavigation.
    // Setting a selection will clear it, so save it to possibly restore later.
    // Note: the START position type is arbitrary because it is unused, it would be
    // the requested position type if there were no xPosForVerticalArrowNavigation set.
    LayoutUnit x = lineDirectionPointForBlockDirectionNavigation(START);
    m_selection.setIsDirectional(shouldAlwaysUseDirectionalSelection(frame()) || alter == FrameSelection::AlterationExtend);

    switch (alter) {
    case FrameSelection::AlterationMove:
        m_frameSelection->moveTo(position, userTriggered);
        break;
    case FrameSelection::AlterationExtend:

        if (!m_selection.isCaret()
            && (granularity == WordGranularity || granularity == ParagraphGranularity || granularity == LineGranularity)
            && frame() && !frame()->editor().behavior().shouldExtendSelectionByWordOrLineAcrossCaret()) {
            // Don't let the selection go across the base position directly. Needed to match mac
            // behavior when, for instance, word-selecting backwards starting with the caret in
            // the middle of a word and then word-selecting forward, leaving the caret in the
            // same place where it was, instead of directly selecting to the end of the word.
            VisibleSelection newSelection = m_selection;
            newSelection.setExtent(position);
            if (m_selection.isBaseFirst() != newSelection.isBaseFirst())
                position = m_selection.visibleBase();
        }

        // Standard Mac behavior when extending to a boundary is grow the
        // selection rather than leaving the base in place and moving the
        // extent. Matches NSTextView.
        if (!frame() || !frame()->editor().behavior().shouldAlwaysGrowSelectionWhenExtendingToBoundary()
            || m_selection.isCaret()
            || !isBoundary(granularity)) {
            m_frameSelection->setExtent(position, userTriggered);
        } else {
            TextDirection textDirection = directionOfEnclosingBlock();
            if (direction == DirectionForward || (textDirection == LTR && direction == DirectionRight) || (textDirection == RTL && direction == DirectionLeft))
                m_frameSelection->setEnd(position, userTriggered);
            else
                m_frameSelection->setStart(position, userTriggered);
        }
        break;
    }

    if (granularity == LineGranularity || granularity == ParagraphGranularity)
        m_xPosForVerticalArrowNavigation = x;

    return true;
}