C++ OptionElement::setSelectedState方法代码示例

void SelectElement::reset(SelectElementData& data, Element* element)
{
    bool optionSelected = false;
    OptionElement* firstOption = 0;

    const Vector<Element*>& items = data.listItems(element);
    for (unsigned i = 0; i < items.size(); ++i) {
        OptionElement* optionElement = toOptionElement(items[i]);
        if (!optionElement)
            continue;

        if (!items[i]->getAttribute(HTMLNames::selectedAttr).isNull()) {
            optionElement->setSelectedState(true);
            optionSelected = true;
        } else
            optionElement->setSelectedState(false);

        if (!firstOption)
            firstOption = optionElement;
    }

    if (!optionSelected && firstOption && data.usesMenuList())
        firstOption->setSelectedState(true);

    element->setNeedsStyleRecalc();
}

void SelectElement::updateListBoxSelection(SelectElementData& data, Element* element, bool deselectOtherOptions)
{
    ASSERT(element->renderer() && element->renderer()->isListBox());
    ASSERT(data.activeSelectionAnchorIndex() >= 0);

    unsigned start = min(data.activeSelectionAnchorIndex(), data.activeSelectionEndIndex());
    unsigned end = max(data.activeSelectionAnchorIndex(), data.activeSelectionEndIndex());
    Vector<bool>& cachedStateForActiveSelection = data.cachedStateForActiveSelection();

    const Vector<Element*>& items = data.listItems(element);
    for (unsigned i = 0; i < items.size(); ++i) {
        OptionElement* optionElement = toOptionElement(items[i]);
        if (!optionElement || items[i]->disabled())
            continue;

        if (i >= start && i <= end)
            optionElement->setSelectedState(data.activeSelectionState());
        else if (deselectOtherOptions || i >= cachedStateForActiveSelection.size())
            optionElement->setSelectedState(false);
        else
            optionElement->setSelectedState(cachedStateForActiveSelection[i]);
    }

    scrollToSelection(data, element);
}

void SelectElement::recalcListItems(SelectElementData& data, const Element* element, bool updateSelectedStates)
{
    Vector<Element*>& listItems = data.rawListItems();
    listItems.clear();

    OptionElement* foundSelected = 0;
    for (Node* currentNode = element->firstChild(); currentNode;) {
        if (!currentNode->isElementNode()) {
            currentNode = currentNode->traverseNextSibling(element);
            continue;
        }

        Element* current = static_cast<Element*>(currentNode);

        // optgroup tags may not nest. However, both FireFox and IE will
        // flatten the tree automatically, so we follow suit.
        // (http://www.w3.org/TR/html401/interact/forms.html#h-17.6)
        if (isOptionGroupElement(current)) {
            listItems.append(current);
            if (current->firstChild()) {
                currentNode = current->firstChild();
                continue;
            }
        }

        if (OptionElement* optionElement = toOptionElement(current)) {
            listItems.append(current);

            if (updateSelectedStates) {
                if (!foundSelected && (data.usesMenuList() || (!data.multiple() && optionElement->selected()))) {
                    foundSelected = optionElement;
                    foundSelected->setSelectedState(true);
                } else if (foundSelected && !data.multiple() && optionElement->selected()) {
                    foundSelected->setSelectedState(false);
                    foundSelected = optionElement;
                }
            }
        }

        if (current->hasTagName(HTMLNames::hrTag))
            listItems.append(current);

        // In conforming HTML code, only <optgroup> and <option> will be found
        // within a <select>. We call traverseNextSibling so that we only step
        // into those tags that we choose to. For web-compat, we should cope
        // with the case where odd tags like a <div> have been added but we
        // handle this because such tags have already been removed from the
        // <select>'s subtree at this point.
        currentNode = currentNode->traverseNextSibling(element);
    }

    data.setShouldRecalcListItems(false);
}

void SelectElement::listBoxDefaultEventHandler(SelectElementData& data, Element* element, Event* event, HTMLFormElement* htmlForm)
{
    const Vector<Element*>& listItems = data.listItems(element);

    if (event->type() == eventNames().mousedownEvent && event->isMouseEvent() && static_cast<MouseEvent*>(event)->button() == LeftButton) {
        element->focus();

        // Convert to coords relative to the list box if needed.
        MouseEvent* mouseEvent = static_cast<MouseEvent*>(event);
        IntPoint localOffset = roundedIntPoint(element->renderer()->absoluteToLocal(mouseEvent->absoluteLocation(), false, true));
        int listIndex = static_cast<RenderListBox*>(element->renderer())->listIndexAtOffset(localOffset.x(), localOffset.y());
        if (listIndex >= 0) {
            // Save the selection so it can be compared to the new selection when dispatching change events during mouseup, or after autoscroll finishes.
            saveLastSelection(data, element);

            data.setActiveSelectionState(true);
            
            bool multiSelectKeyPressed = false;
#if PLATFORM(MAC)
            multiSelectKeyPressed = mouseEvent->metaKey();
#else
            multiSelectKeyPressed = mouseEvent->ctrlKey();
#endif

            bool shiftSelect = data.multiple() && mouseEvent->shiftKey();
            bool multiSelect = data.multiple() && multiSelectKeyPressed && !mouseEvent->shiftKey();

            Element* clickedElement = listItems[listIndex];            
            OptionElement* option = toOptionElement(clickedElement);
            if (option) {
                // Keep track of whether an active selection (like during drag selection), should select or deselect
                if (option->selected() && multiSelectKeyPressed)
                    data.setActiveSelectionState(false);

                if (!data.activeSelectionState())
                    option->setSelectedState(false);
            }
            
            // If we're not in any special multiple selection mode, then deselect all other items, excluding the clicked option.
            // If no option was clicked, then this will deselect all items in the list.
            if (!shiftSelect && !multiSelect)
                deselectItems(data, element, clickedElement);

            // If the anchor hasn't been set, and we're doing a single selection or a shift selection, then initialize the anchor to the first selected index.
            if (data.activeSelectionAnchorIndex() < 0 && !multiSelect)
                setActiveSelectionAnchorIndex(data, element, selectedIndex(data, element));

            // Set the selection state of the clicked option
            if (option && !clickedElement->disabled())
                option->setSelectedState(true);
            
            // If there was no selectedIndex() for the previous initialization, or
            // If we're doing a single selection, or a multiple selection (using cmd or ctrl), then initialize the anchor index to the listIndex that just got clicked.
            if (listIndex >= 0 && (data.activeSelectionAnchorIndex() < 0 || !shiftSelect))
                setActiveSelectionAnchorIndex(data, element, listIndex);
            
            setActiveSelectionEndIndex(data, listIndex);
            updateListBoxSelection(data, element, !multiSelect);

            if (Frame* frame = element->document()->frame())
                frame->eventHandler()->setMouseDownMayStartAutoscroll();

            event->setDefaultHandled();
        }
    } else if (event->type() == eventNames().mouseupEvent && event->isMouseEvent() && static_cast<MouseEvent*>(event)->button() == LeftButton && element->document()->frame()->eventHandler()->autoscrollRenderer() != element->renderer())
        // This makes sure we fire dispatchFormControlChangeEvent for a single click.  For drag selection, onChange will fire when the autoscroll timer stops.
        listBoxOnChange(data, element);
    else if (event->type() == eventNames().keydownEvent) {
        if (!event->isKeyboardEvent())
            return;
        String keyIdentifier = static_cast<KeyboardEvent*>(event)->keyIdentifier();

        int endIndex = 0;        
        if (data.activeSelectionEndIndex() < 0) {
            // Initialize the end index
            if (keyIdentifier == "Down")
                endIndex = nextSelectableListIndex(data, element, lastSelectedListIndex(data, element));
            else if (keyIdentifier == "Up")
                endIndex = previousSelectableListIndex(data, element, optionToListIndex(data, element, selectedIndex(data, element)));
        } else {
            // Set the end index based on the current end index
            if (keyIdentifier == "Down")
                endIndex = nextSelectableListIndex(data, element, data.activeSelectionEndIndex());
            else if (keyIdentifier == "Up")
                endIndex = previousSelectableListIndex(data, element, data.activeSelectionEndIndex());    
        }
        
        if (keyIdentifier == "Down" || keyIdentifier == "Up") {
            // Save the selection so it can be compared to the new selection when dispatching change events immediately after making the new selection.
            saveLastSelection(data, element);

            ASSERT(endIndex >= 0 && (unsigned) endIndex < listItems.size()); 
            setActiveSelectionEndIndex(data, endIndex);
            
            // If the anchor is unitialized, or if we're going to deselect all other options, then set the anchor index equal to the end index.
            bool deselectOthers = !data.multiple() || !static_cast<KeyboardEvent*>(event)->shiftKey();
            if (data.activeSelectionAnchorIndex() < 0 || deselectOthers) {
                data.setActiveSelectionState(true);
                if (deselectOthers)
                    deselectItems(data, element);
//.........这里部分代码省略.........