popupmenuchromium.cpp

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        gc->fillRect(rowRect, Color::white);

    gc->fillRect(rowRect, backColor);
    
    if (m_popupClient->itemIsSeparator(rowIndex)) {
        IntRect separatorRect(
            rowRect.x() + separatorPadding,
            rowRect.y() + (rowRect.height() - separatorHeight) / 2,
            rowRect.width() - 2 * separatorPadding, separatorHeight);
        gc->fillRect(separatorRect, textColor);
        return;
    }
    
    gc->setFillColor(textColor);

    // Bunch of shit to deal with RTL text...
    String itemText = m_popupClient->itemText(rowIndex);
    unsigned length = itemText.length();
    const UChar* str = itemText.characters();

    TextRun textRun(str, length, false, 0, 0, itemText.defaultWritingDirection() == WTF::Unicode::RightToLeft);

    // FIXME: http://b/1210481 We should get the padding of individual option
    // elements.  This probably implies changes to PopupMenuClient.

    // Draw the item text
    if (style.isVisible()) {
        Font itemFont = getRowFont(rowIndex);
        int textX = max(0, m_popupClient->clientPaddingLeft() - m_popupClient->clientInsetLeft());
        int textY = rowRect.y() + itemFont.ascent() + (rowRect.height() - itemFont.height()) / 2;
        gc->drawBidiText(itemFont, textRun, IntPoint(textX, textY));
    }
}

Font PopupListBox::getRowFont(int rowIndex)
{
    Font itemFont = m_popupClient->itemStyle(rowIndex).font();
    if (m_popupClient->itemIsLabel(rowIndex)) {
        // Bold-ify labels (ie, an <optgroup> heading).
        FontDescription d = itemFont.fontDescription();
        d.setWeight(FontWeightBold);
        Font font(d, itemFont.letterSpacing(), itemFont.wordSpacing());
        font.update(0);
        return font;
    }

    return itemFont;
}

void PopupListBox::abandon()
{
    RefPtr<PopupListBox> keepAlive(this);

    m_selectedIndex = m_originalIndex;

    m_popupClient->hidePopup();

    if (m_willAcceptOnAbandon)
        m_popupClient->valueChanged(m_selectedIndex);
}

int PopupListBox::pointToRowIndex(const IntPoint& point)
{
    int y = scrollY() + point.y();

    // FIXME: binary search if perf matters.
    for (int i = 0; i < numItems(); ++i) {
        if (y < m_items[i]->y)
            return i-1;
    }

    // Last item?
    if (y < contentsHeight())
        return m_items.size()-1;

    return -1;
}

void PopupListBox::acceptIndex(int index)
{
    ASSERT(index >= -1 && index < numItems());
    if (index == -1 && m_popupClient) {
      // Enter pressed with no selection, just close the popup.
      m_popupClient->hidePopup();
      return;
    }

    if (isSelectableItem(index)) {
        RefPtr<PopupListBox> keepAlive(this);

        // Hide ourselves first since valueChanged may have numerous side-effects.
        m_popupClient->hidePopup();

        // Tell the <select> PopupMenuClient what index was selected.
        m_popupClient->valueChanged(index);
    }
}

void PopupListBox::selectIndex(int index)
{
    ASSERT(index >= 0 && index < numItems());

    if (index != m_selectedIndex && isSelectableItem(index)) {
        invalidateRow(m_selectedIndex);
        m_selectedIndex = index;
        invalidateRow(m_selectedIndex);

        scrollToRevealSelection();
    }
}

void PopupListBox::setOriginalIndex(int index)
{
    m_originalIndex = m_selectedIndex = index;
}

int PopupListBox::getRowHeight(int index)
{
    if (index < 0)
        return 0;

    return m_popupClient->itemStyle(index).font().height();
}

IntRect PopupListBox::getRowBounds(int index)
{
    if (index < 0)
        return IntRect(0, 0, visibleWidth(), getRowHeight(index));

    return IntRect(0, m_items[index]->y, visibleWidth(), getRowHeight(index));
}

void PopupListBox::invalidateRow(int index)
{
    if (index < 0)
        return;

    // Invalidate in the window contents, as FramelessScrollView::invalidateRect
    // paints in the window coordinates.
    invalidateRect(contentsToWindow(getRowBounds(index)));
}

void PopupListBox::scrollToRevealRow(int index)
{
    if (index < 0)
        return;

    IntRect rowRect = getRowBounds(index);
 
    if (rowRect.y() < scrollY()) {
        // Row is above current scroll position, scroll up.
        ScrollView::setScrollPosition(IntPoint(0, rowRect.y()));
    } else if (rowRect.bottom() > scrollY() + visibleHeight()) {
        // Row is below current scroll position, scroll down.
        ScrollView::setScrollPosition(IntPoint(0, rowRect.bottom() - visibleHeight()));
    }
}

bool PopupListBox::isSelectableItem(int index)
{
    return m_items[index]->type == TypeOption && m_popupClient->itemIsEnabled(index);
}

void PopupListBox::clearSelection()
{
    if (m_selectedIndex != -1) {
        invalidateRow(m_selectedIndex);
        m_selectedIndex = -1;
    }
}

void PopupListBox::selectNextRow()
{
    if (!m_settings.loopSelectionNavigation || m_selectedIndex != numItems() - 1) {
        adjustSelectedIndex(1);
        return;
    }

    // We are moving past the last item, no row should be selected.
    clearSelection();
}

void PopupListBox::selectPreviousRow()
{
    if (!m_settings.loopSelectionNavigation || m_selectedIndex > 0) {
        adjustSelectedIndex(-1);
        return;
    }

    if (m_selectedIndex == 0) {
        // We are moving past the first item, clear the selection.
        clearSelection();
        return;
    }

    // No row are selected, jump to the last item.
    selectIndex(numItems() - 1);
    scrollToRevealSelection();
}

void PopupListBox::adjustSelectedIndex(int delta)
{
    int targetIndex = m_selectedIndex + delta;
    targetIndex = min(max(targetIndex, 0), numItems() - 1);
    if (!isSelectableItem(targetIndex)) {
        // We didn't land on an option.  Try to find one.
        // We try to select the closest index to target, prioritizing any in
        // the range [current, target].

        int dir = delta > 0 ? 1 : -1;
        int testIndex = m_selectedIndex;
        int bestIndex = m_selectedIndex;
        bool passedTarget = false;
        while (testIndex >= 0 && testIndex < numItems()) {
            if (isSelectableItem(testIndex))
                bestIndex = testIndex;
            if (testIndex == targetIndex)
                passedTarget = true;
            if (passedTarget && bestIndex != m_selectedIndex)
                break;

            testIndex += dir;
        }

        // Pick the best index, which may mean we don't change.
        targetIndex = bestIndex;
    }

    // Select the new index, and ensure its visible.  We do this regardless of
    // whether the selection changed to ensure keyboard events always bring the
    // selection into view.
    selectIndex(targetIndex);
    scrollToRevealSelection();
}

void PopupListBox::updateFromElement()
{
    // It happens when pressing a key to jump to an item, then use tab or
    // mouse to get away from the select box. In that case, updateFromElement
    // is called before abandon, which causes discarding of the select result.    
    if (m_willAcceptOnAbandon) {
        m_popupClient->valueChanged(m_selectedIndex);
        m_willAcceptOnAbandon = false;
    }

    clear();

    int size = m_popupClient->listSize();
    for (int i = 0; i < size; ++i) {
        ListItemType type;
        if (m_popupClient->itemIsSeparator(i))
            type = PopupListBox::TypeSeparator;
        else if (m_popupClient->itemIsLabel(i))
            type = PopupListBox::TypeGroup;
        else
            type = PopupListBox::TypeOption;
        m_items.append(new ListItem(m_popupClient->itemText(i), type));
    }

    m_selectedIndex = m_popupClient->selectedIndex();
    setOriginalIndex(m_selectedIndex);

    layout();
}

void PopupListBox::layout()
{
    // Size our child items.
    int baseWidth = 0;
    int paddingWidth = 0;
    int y = 0;
    for (int i = 0; i < numItems(); ++i) {
        Font itemFont = getRowFont(i);

        // Place the item vertically.
        m_items[i]->y = y;
        y += itemFont.height();

        // Ensure the popup is wide enough to fit this item.
        String text = m_popupClient->itemText(i);
        if (!text.isEmpty()) {
            int width = itemFont.width(TextRun(text));
            baseWidth = max(baseWidth, width);
        }
        // FIXME: http://b/1210481 We should get the padding of individual option elements.
        paddingWidth = max(paddingWidth, 
            m_popupClient->clientPaddingLeft() + m_popupClient->clientPaddingRight());
    }

    int windowHeight = 0;
    m_visibleRows = min(numItems(), kMaxVisibleRows);
    for (int i = 0; i < m_visibleRows; ++i) {
        int rowHeight = getRowHeight(i);
        if (windowHeight + rowHeight > kMaxHeight) {
            m_visibleRows = i;
            break;
        }

        windowHeight += rowHeight;
    }

    // Set our widget and scrollable contents sizes.
    int scrollbarWidth = 0;
    if (m_visibleRows < numItems())
        scrollbarWidth = ScrollbarTheme::nativeTheme()->scrollbarThickness();

    int windowWidth = baseWidth + scrollbarWidth + paddingWidth;
    int contentWidth = baseWidth;

    if (windowWidth < m_baseWidth) {
        windowWidth = m_baseWidth;
        contentWidth = m_baseWidth - scrollbarWidth - paddingWidth;
    } else {
        m_baseWidth = baseWidth;
    }

    resize(windowWidth, windowHeight);
    setContentsSize(IntSize(contentWidth, getRowBounds(numItems() - 1).bottom()));

    if (hostWindow())
        scrollToRevealSelection();

    invalidate();
}

void PopupListBox::clear()
{
    for (Vector<ListItem*>::iterator it = m_items.begin(); it != m_items.end(); ++it)
        delete *it;
    m_items.clear();
}

bool PopupListBox::isPointInBounds(const IntPoint& point)
{
    return numItems() != 0 && IntRect(0, 0, width(), height()).contains(point);
}

///////////////////////////////////////////////////////////////////////////////
// PopupMenu implementation
// 
// Note: you cannot add methods to this class, since it is defined above the 
//       portability layer. To access methods and properties on the
//       popup widgets, use |popupWindow| above. 

PopupMenu::PopupMenu(PopupMenuClient* client) 
    : m_popupClient(client)
{
}

PopupMenu::~PopupMenu()
{
    hide();
}

void PopupMenu::show(const IntRect& r, FrameView* v, int index) 
{
    if (!p.popup)
        p.popup = PopupContainer::create(client(), dropDownSettings);
    p.popup->show(r, v, index);
}

void PopupMenu::hide()
{
    if (p.popup)
        p.popup->hidePopup();
}

void PopupMenu::updateFromElement()
{
    p.popup->listBox()->updateFromElement();
}

bool PopupMenu::itemWritingDirectionIsNatural() 
{ 
    return false; 
}

} // namespace WebCore